Dissertations / Theses: 'Bioactive compounds of food'

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Martínez, Micaelo Nieves Beatriz. "Nutritional Immunotherapy: targeting immunometabolism with bioactive food compounds." Doctoral thesis, Universitat Rovira i Virgili, 2014. http://hdl.handle.net/10803/401827.

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La immunoteràpia nutricional es basa en fomentar la salut mitjançant el consum de compostos bioactius presents de manera natural en els aliments, com les procianidines, un tipus de flavonoid, i/o l’àcid docosahexaenoic (DHA), un àcid gras omega-3, optimitzant la funcionalitat del propi sistema immune i millorant així el seu paper com a responsable de la preservació de l’organisme enfront desestabilitzadors de la homeòstasis. La recerca que aquesta tesi abasta es centra en el paper del perfil nutricional en la regulació de la interacció immunitat-metabolisme (immunometabolisme). Amb aquesta finalitat, en la primera part del treball presentat en aquesta tesi, es va determinar si els macròfags, les cèl•lules efectores de la immunitat innata, poden percebre de manera diferencial la composició de la dieta. Hem demostrat que els compostos bioactius dels aliments modulen, a nivell molecular, l’activació dels macròfags. A més, aquest efecte immunomodulador és dependent del compost, on factors intrínsecs com les propietats químiques o nutritives són determinants per la seva bioactivitat. La segona part va tenir com a objectiu determinar el paper primordial del patró nutricional en la regulació de la interacció entre el sistema immune i el metabolisme. Utilitzant un model d’obesitat induïda per la dieta es va inferir que, mentre una dieta hipercalòrica provoca un deteriorament de l’immunometabolisme, el consum de bioactius pot enfortir-ne la relació. A la tercera part, es va analitzar el paper de les interaccions gen-dieta en l’expressió fenotípica dels trets associats amb la obesitat. Per aquest motiu, dos races de rates congènites, fenotípicament diferents, van ser sotmeses a un desequilibri immunometabòlic com a conseqüència de la ingesta d’una dieta hipercalòrica. Es va deduir que les interaccions entre els factors genètics i nutricionals són fonamentals per a la susceptibilitat d’un genotip a l’obesitat induïda per la dieta. Hem establert que el perfil nutricional és una eina poderosa per orientar la funcionalitat de l’eix immunometabòlic. A més, arribem a la conclusió que compostos bioactius presents en els aliments poden millorar-ne l’eficiència d’aquest eix, promovent així un estat saludable.
La immunoterapia nutricional se basa en fomentar la salud mediante el consumo de componentes bioactivos presentes de forma natural en los alimentos, como las procianidinas, un tipo de flavonoides, o el ácido docosahexaenoico (DHA), un ácido graso omega-3, optimizando la funcionalidad del propio sistema inmune y mejorando así su papel como responsable de la preservación del organismo frente a desestabilizadores de la homeostasis. La investigación que engloba esta tesis se centra en el papel del perfil nutricional en la regulación de la interacción inmunidad-metabolismo (immunometabolismo). Con esta finalidad, en la primera parte del trabajo presentado es esta tesis, se determinó si los macrófagos, las células efectoras de la inmunidad innata, pueden percibir de manera diferencial la composición de la dieta. Hemos demostrado que los compuestos bioactivos de los alimentos modulan, a nivel molecular, la activación de los macrófagos. Además, este efecto immunomodulador es dependiente del compuesto, donde factores intrínsecos tales como sus propiedades químicas o nutritivas son determinantes para su bioactividad. La segunda parte tuvo como objetivo determinar el papel primordial del patrón nutricional en la regulación de la interacción entre el sistema inmune y el metabolismo. Utilizando un modelo de obesidad inducida por la dieta se infirió que, mientras una dieta hipercalórica provoca un deterioro del immunometabolismo, el consumo de bioactivos pueden fortalecer su estrecha relación. En la tercera parte, se analizó el papel de las interacciones gen-dieta en la expresión fenotípica de los rasgos asociados con la obesidad. Para ello, dos razas de ratas congénitas, fenotípicamente diferentes, fueron sometidas a un desequilibrio immunometabólico como consecuencia de la ingesta de una dieta hipercalórica. Se dedujo que las interacciones entre los factores genéticos y nutricionales son fundamentales para la susceptibilidad de un genotipo a la obesidad inducida por la dieta. Hemos establecido que el perfil nutricional es una herramienta poderosa para orientar la funcionalidad del eje immunometabólico. Además, llegamos a la conclusión que compuestos bioactivos presentes en los alimentos pueden mejorar la eficiencia de este eje, promoviendo así un estado saludable.
Nutritional immunotherapy is based on promoting health through the dietary intake of natural bioactive compounds found in food, such as the procyanidins and docosahexaenoic n-3 polyunsaturated fatty acid (DHA), optimising the functionality of the host’s own immune system and improving its role in the preservation of the body against destabilisers of homeostasis. The research that this thesis encompasses is focused on the role of the nutritional profile in the regulation of immunometabolism. To accomplish this purpose, in the first part of the work presented in this thesis, we determined whether macrophages, the effector cells of innate immunity, could differentially sense dietary composition. We demonstrated that bioactive food compounds modulate, at the molecular level, the functionality of macrophages by hindering macrophage activation. Furthermore, this immunomodulatory effect is compound-dependent, relying on the intrinsic factors of each compound, such as chemical and nutritional properties, to determine its bioactivity. The second part was aimed at determining the role of the dietary pattern within the complex crosstalk of immunity and metabolism using an in vivo model of diet-induced obesity. We determined that immunometabolic regulation depends on the nutritional profile. While a diet based on foods with a high energy content can weaken immunometabolism, the presence of bioactive foods can strengthen the relationship. Within the third part, we evaluated the role of gene-diet interactions in the phenotypic expression of obesity-related complex traits. Using a diet-induced obesity model, two distinct genetic backgrounds (phenotypically different inbred rat strains) were immunometabolically challenged. Our results revealed that interactions between genetic and dietary factors are fundamental for the susceptibility of a genotype to diet-induced obesity. We established that the nutritional profile is a powerful tool to target the functionality of the immunometabolic axis. We further concluded that bioactive compounds present in food improve the efficiency of this axis, thereby promoting a healthy state.

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Pallarés, López víctor. "Role of bioactive food compounds in acute and chronic inflammation." Doctoral thesis, Universitat Rovira i Virgili, 2012. http://hdl.handle.net/10803/96658.

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En els últims anys, s’ha estudiat com els agents antiinflamatoris presents en els aliments poden modular la inflamació relacionada amb diverses malalties. Les procianidines presents en fruites i vegetals i els àcids grassos poliinsaturats (PUFAs) presents en peix i els olis derivats d’ells són compostos que tenen diferents propietats antiinflamatòries en front de diverses malalties com l’obesitat, la diabetis i malalties cardiovasculars. L’objectiu del nostre estudi va ser investigar diferents aspectes i mecanismes relacionats amb l’eficàcia d’un extracte de procianidines de pinyol de raïm (GSPE) en front de l’estat inflamatori crònic en rates Zucker fa/fa genèticament obeses, i d’un estat inflamatori agut activat per la injecció de lipopolisacàrids (LPS) en rates Wistar. Una dosi moderada de 35 mg/kg per dia de GSPE durant 10 setmanes va produir efectes antiinflamatoris sobre l’expressió gènica en teixit adipós mesentèric en les rates Zucker fa/fa. Tot i així, no es van trobar efectes significatius en la inflamació sistèmica. A més, el GSPE va tenir efectes antiinflamatoris a nivell sistèmic i en l’expressió gènica quan es va administrar durant 15 dies previs a la inducció de la inflamació per LPS en rates Wistar. La dosi alta nutricional de 75 mg/kg per dia i la dosi alta farmacològica de 200 mg/kg per dia de GSPE van ser les més efectives en prevenir aquesta inflamació. Per altra banda, diferents molècules bioactives com els flavonoides resveratrol (RES), epigal•locatequina gal•lat, i les procianidines dimèriques B1-B4, i els PUFAs EPA i DHA van ser administrats en combinació per analitzar els efectes antiinflamatoris sinèrgics, additius o antagònics en macròfags estimulats amb LPS. Les combinacions de B3 més EPA i RES més EPA van mostrar efectes antiinflamatoris sinèrgics disminuint els nivells d’òxid nítric, els nivells d’expressió de gens proinflamatoris i relacionats amb l’estrès oxidatiu, i modulant la fosforilació de diferents proteïnes involucrades en l’activació de les vies proinflamatòries senyalitzadores de l’NF-κB i de l’AP-1.
The study of how anti-inflammatory agents found in food can mediate in various diseases in which inflammation is involved has become relevant in recent years. Procyanidins present in fruits and vegetables and polyunsaturated fatty acids (PUFAs) present in fish and fish oils are compounds that have anti-inflammatory properties against several diseases such as obesity, diabetes and cardiovascular disease. The goal of this study was to investigate some aspects and mechanisms related to the reported efficacy of grape seed procyanidin extract (GSPE) against the inflammatory state in the genetically obese Zucker fa/fa rat model with low-chronic inflammation and a model of acute inflammation triggered by the injection of lipopolysaccharide (LPS) into Wistar rats. A moderate dose of 35 mg/kg*day of GSPE for 10 weeks had anti-inflammatory effects at the gene expression level in mesenteric adipose tissue in Zucker fa/fa rats. However, no significant effects on systemic inflammation were found. In contrast, GSPE had anti-inflammatory effects at the systemic and gene expression levels when administered for 15 days prior to LPS-induced inflammation in Wistar rats. The moderate-high dose of 75 mg/kg*day and the high dose of 200 mg/kg*day of GSPE were the most effective doses in preventing acute inflammation. In addition, several pure bioactive flavonoids such as resveratrol (RES), epigallocatechin gallate, B1-B4 dimeric procyanidins, and PUFAs such as EPA and DHA were administered in various combinations to assess any potential synergistic, additive or antagonistic anti-inflammatory effects that may exist between these flavonoids and PUFAs in LPS-stimulated murine macrophages. Importantly, the combinations of B3 plus EPA and RES plus EPA had strong synergistic anti-inflammatory effects manifested by a decrease in nitric oxide levels, a decrease in the expression of proinflammatory and oxidative stress-related genes and the modulation of the phosphorylation status of various proteins involved in the activation of the NF-κB and AP-1 proinflammatory pathways.
En los últimos años, se ha estudiado como los agentes antinflamatorios presentes en los alimentos pueden modular la inflamación relacionada con diversas enfermedades. Las procianidinas presentes en frutas y vegetales y los ácidos grasos polinsaturados (PUFAs) presentes en el pescado y los aceites derivados de ellos son compuestos que tienen diferentes propiedades antinflamatorias frente a varias enfermedades como la obesidad, la diabetes y enfermedades cardiovasculares. El objetivo de nuestro estudio fue investigar diferentes aspectos y mecanismos relacionados con la eficacia de un extracto de procianidinas de pepita de uva (GSPE) frente al estado inflamatorio crónico en ratas Zucker fa/fa genéticamente obesas, y de un estado inflamatorio agudo activado por la inyección de lipopolisacáridos (LPS) en ratas Wistar. Una dosis moderada de 35 mg/kg por día de GSPE durante 10 semanas produjo efectos antinflamatorios sobre la expresión génica en tejido adiposo mesentérico en las ratas Zucker fa/fa. Aún así, no se encontraron efectos significativos en la inflamación sistémica. Además, el GSPE tuvo efectos antinflamatorios a nivel sistémico y en la expresión génica cuando fue administrado durante 15 días previos a la inducción de la inflamación por LPS en ratas Wistar. La dosis alta nutricional de 75 mg/kg por día y la dosis alta farmacológica de 200 mg/kg por día de GSPE fueron las más efectivas en prevenir esta inflamación. Por otro lado, diferentes moléculas bioactivas como los flavonoides resveratrol (RES), epigalocatequina galada, y las procianidinas diméricas B1-B4, y los PUFAs EPA y DHA fueron administrados en combinación para analizar los efectos antinflamatorios sinérgicos, aditivos o antagónicos en macrófagos estimulados con LPS. Las combinaciones de B3 más EPA y RES más EPA mostraron efectos antinflamatorios sinérgicos disminuyendo los niveles de óxido nítrico, los niveles de expresión de genes proinflamatorios y relacionados con el estrés oxidativo, y modulando la fosforilación de diferentes proteínas involucradas en la activación de las vías proinflamatorias señalizadoras del NF-κB y del AP-1.

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Fradinho, Patrícia Catarina das Neves Bordalo Branco. "Gluten-free fresh pasta enriched with bioactive compounds." Doctoral thesis, ISA, 2020. http://hdl.handle.net/10400.5/21203.

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Doutoramento em Engenharia Alimentar / Instituto Superior de Agronomia. Universidade de Lisboa
Sustainability of the agri-food chain is on today’s agenda, whether through the use of industrial byproducts or the investigation of alternative sources of ingredients. The increasing number of individuals with gluten-related diseases, but also consumers following a gluten-free diet are the drivers for the continually growing number of gluten-free products launched in the market. However, in addition to their still limited commercial availability and high price compared to their wheat counterparts, gluten-free products show nutritional deficiencies. Following the current consumer trends for healthy foods with underlying sustainable principles (ingredients and processes), this thesis aimed the development of a gluten-free fresh pasta based on rice flour from broken grains and Psyllium husk, enriched with Arthrospira platensis, Laminaria ochroleuca and potato peel. Firstly, the gelatinisation (5 – 26%) of rice flour from broken rice (rice processing industry by-product) was performed to assess the optimum conditions for producing gluten-free pasta. Afterwards, the pasta formulation (50% gelatinised rice flour/rice flour) was successfully optimized, and its structure reinforced with 4% Psyllium husk gel. This gluten-free pasta was then enriched with bioactive compound sources (Arthrospira platensis, Laminaria ochroleuca and potato peel) incorporated as lyophilised biomass, gel or liquid extract obtained by subcritical water extraction (autohydrolysis), an eco-friendly technology. The pastas developed were characterized in terms of cooking quality parameters, texture, colour, rheology, nutritional composition, antioxidant activity, in vitro digestibility and sensory analysis. It was found that autohydrolysis was a suitable technology for the valorisation of distinct materials, namely marine and industrial. Pastas with Laminaria ochroleuca provided a high mineral and fibre contents, and low-fat content, so that could bear nutritional claims. On the other hand, Arthrospira platensis incorporation proved to have a positive effect on the pasta antioxidant activity and overall sensory analysis without affecting the in vitro digestibility. Pasta with potato peel extract presented a high total phenolic content and antioxidant activity. All formulations presented good overall cooking quality and texture and rheology properties
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Catalán, Santos Úrsula. "Effect of food extracts and bioactive food compounds on the mechanism of atherosclerosis and nutritional biomarkers." Doctoral thesis, Universitat Rovira i Virgili, 2012. http://hdl.handle.net/10803/84046.

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Primera, estudiar los efectos de un extracto de cacahuete rico en polifenoles y de compuestos bioactivos (alfa-tocoferol) en modelos celulares a nivel de inflamación (células monocíticas THP-1) y disfunción endotelial (células endoteliales de aorta humana; HAEC), respectivamente. Segunda, optimizar el volumen sanguíneo caracterizando el perfil de metabolitos acuosos y lipídicos, la composición de ácidos grasos, la detección de subclases de lipoproteínas y de polifenoles en plasma y glóbulos rojos. El extracto de cacahuete ejerce efectos anti-inflamatorios mediante la inhibición de la proteína del TNF-α extracelular, a través de la inhibición de la activación del factor de transcripción c-Jun. El alfa-tocoferol mejora la función endotelial mediante la inhibición de la VCAM-1 y en menor grado sobre la E-selectina e ICAM-1. El plasma y glóbulos rojos aportan información metabolómica complementaria y se elegirá uno u otro en función del objetivo de los estudios en humanos.
The thesis addresses two major issues. Firstly: The study the effects of polyphenol-rich peanut extract and bioactive compounds (alpha-tocopherol) in cellular models of inflammation (monocytic cells; THP-1) and on endothelial dysfunction (human aortic endothelial cells; HAEC), respectively. Secondly: The optimisation of blood sampling for human studies to characterise the profile of aqueous and lipid metabolites, fatty acid composition, lipoprotein subclasses, and polyphenol content of plasma and red blood cells. Peanut extract exerts anti-inflammatory effects by inhibiting extracellular TNF-α protein via the inhibition of c-Jun transcription factor activation. Alpha-tocopherol improves endothelial function by inhibiting VCAM-1 and, to a lesser extent, E-selectin and ICAM-1. Analyses of metabolites in plasma and red blood cells generate complementary information. The measurements may need to be performed in either, or both, matrices, depending on the objectives of the study.

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Arguelles, Mercedes C. "FOOD AND FOOD-DERIVED BIOACTIVE COMPOUNDS: RELEVANCE TO HOMEOSTASIS OF THE ANTIOXIDANT, CARDIOVASCULAR, AND IMMUNE SYSTEMS." Diss., Tucson, Arizona : University of Arizona, 2005. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu%5Fetd%5F1079%5F1%5Fm.pdf&type=application/pdf.

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Pedret, Figuerola Anna. "Bioactive food compounds of Mediterranean and Nordic diets and their effects on nutritional and cardiovascular disease biomarkers." Doctoral thesis, Universitat Rovira i Virgili, 2014. http://hdl.handle.net/10803/284705.

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L’objectiu principal de la tesis és valorar l’impacte de certs compostos bioactius de la dieta Mediterrània i Nòrdica, especialment de compostos fenòlics, sobre marcadors nutricionals i moleculars, els quals permetin determinar mecanismes d’acció i efectes biològics saludables involucrats en el desenvolupament de la malaltia cardiovascular (MCV). Un increment de l’excreció total de polifenols en orina, el qual és un marcador del consum total de polifenols, pot reflectir una atenuació del dany oxidatiu. Els efectes beneficiosos en individus sans d’una ingesta rica en verdures i moderada de vi negre, podrien ser explicats en part per l'atenuació del dany oxidatiu associat amb aquests aliments típics de la dieta mediterrània rica en polifenols. Utilitzant la metabolòmica no dirigida, les concentracions plasmàtiques de l’àcid 3-carboxy-4-methyl-5-propyl-2-furanopropionic, els alk(en)ylresorcinols glucosilats i l’àcid hipúric se suggereixen com a nous candidats de marcadors de consum de peix blau, cereals integrals i nabius, respectivament. Alteracions en marcadors moleculars del metabolisme endogen, com ara lípids que contenen àcids grassos poliinsaturats, aminoàcids i metabolits de la betaïna, podrien explicar els efectes beneficiosos de la dieta Nòrdica, rica en cereals integrals, peix blau i nabius. Mitjançant l’aplicació de proteòmica quantitativa confirmem que, el consum d’oli d’oliva verge o d’olis d’oliva verges enriquits amb fenols té un impacte sobre el proteoma de l’HDL d’una manera cardioprotectora que podria millorar la funcionalitat de l’HDL. L’ús de marcadors nutricionals és una eina útil en l’avaluació dels mecanismes d’acció i dels efectes biològics dels compostos bioactius de la dieta sobre el desenvolupament de la MCV. Així, l’ús de les ciències òmiques, tals com la metabolòmica i la proteòmica, afegeixen informació rellevant en el descobriment de nous marcadors nutricionals i moleculars, els quals ens ajuden a avaluar la bioactivitat dels aliments i els efectes d’aquests sobre la salut humana i la prevenció de les malalties.
El objetivo principal de la tesis es valorar el impacto de ciertos compuestos bioactivos de la dieta Mediterránea y Nórdica, especialmente de compuestos fenólicos, sobre marcadores nutricionales y moleculares, los cuales permitan determinar mecanismos de acción y efectos biológicos saludables involucrados en el desarrollo de la enfermedad cardiovascular (ECV). Un incremento de la excreción total de polifenoles en orina, el cuál es un marcador del consumo total de polifenoles, puede reflejar atenuación del daño oxidativo. Los efectos beneficiosos en individuos sanos de una ingesta rica en verduras y moderada en vino tinto, podrían ser explicados por la atenuación del daño oxidativo asociado con estos alimentos de la dieta mediterránea rica en polifenoles. Utilizando la metabolómica no dirigida, las concentraciones plasmáticas de ácido 3-carboxy-4-methyl-5-propyl-2-furanopropionic, alk(en)ylresorcinols glicosilados y ácido hipúrico se sugieren como nuevos marcadores de consumo de pescado azul, cereales integrales y arándanos, respectivamente. Alteraciones en marcadores moleculares del metabolismo endógeno, como lípidos con ácidos grasos poliinsaturados, aminoácidos y metabolitos de la betaína, podrían explicar los efectos beneficiosos de la dieta Nórdica, rica en cereales integrales, pescado azul y arándanos. Mediante la aplicación de proteómica cuantitativa confirmamos que, el consumo de aceite de oliva virgen (AOV) o de AOVs enriquecidos con fenoles tiene un impacto sobre el proteoma de la HDL de manera cardioprotectora que podría mejorar su funcionalidad. El uso de marcadores nutricionales es una herramienta útil para evaluar los mecanismos de acción y los efectos biológicos de los compuestos bioactivos de la dieta sobre el desarrollo de la ECV. Así, el uso de ciencias ómicas, tales como la metabolómica y la proteómica, añaden información relevante en el descubrimiento de nuevos marcadores nutricionales y moleculares, los cuales nos ayudan a evaluar la bioactividad de los alimentos y los efectos de éstos sobre la salud humana y la prevención de enfermedades.
The main objective of the thesis is to assess the impact of Mediterranean and Nordic dietary bioactive compounds, especially phenolic compounds, on nutritional and molecular biomarkers, which allow to determine mechanisms of action and biological effects involved in the development of CVD. An increased urinary excretion of total polyphenols, which is a biomarker of total polyphenol intake, may reflect an attenuation of oxidative damage. The beneficial effects in healthy individuals of a dietary intake rich in vegetables and moderate red wine, could potentially be explained by the attenuation of oxidative damage associated with these typical food items of the Mediterranean diet rich in polyphenols. By applying a non-targeted metabolite approach, fasting plasma 3-carboxy-4-methyl-5-propyl-2-furanopropionic acid, glucuronidated alk(en)ylresorcinols and hippuric acid are suggested as novel candidate biomarkers of fatty fish, whole grain and bilberries consumption, respectively. Alterations in molecular biomarkers of endogenous metabolism, such as PUFA-containing lipids, amino acids and betaine metabolites could indicate potential effects of a healthy Nordic diet, rich in whole grains, fatty fish and berries. By applying a quantitative proteomic approach we confirm that the consumption of virgin olive oil or phenol-enriched virgin olive oils has an impact on the HDL proteome in a cardioprotective mode that could enhance HDL functionality. The use of nutritional biomarkers is a useful tool in assessing the mechanisms of action and the biological effects of the dietary bioactive compounds on cardiovascular disease development. Thus, the use of omic sciences, such as metabolomics and proteomics, add relevant information in the discovery of novel nutritional and molecular biomarkers, which help us in evaluating the food bioactivity and the food effects on human health and disease prevention.

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Artiga, Artigas María. "Design of nanostructured delivery systems to enhance the functionality of food bioactive compounds." Doctoral thesis, Universitat de Lleida, 2018. http://hdl.handle.net/10803/665007.

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Les nanoestructures basades en emulsions es consideren excel•lents sistemes d'alliberament de compostos bioactius de diferent naturalesa i funcionalitat. L'objectiu d'aquesta Tesi Doctoral va ser estudiar els factors que afecten l'estabilitat de les nanoemulsions i emulsions dobles, com sistemes d'encapsulació de bioactius lipofílics i/o hidrofílics, respectivament; i l'efecte de la seva aplicació en aliments. El tipus i la concentració dels diferents components de les nanoemulsions contenint curcumina o olis essencials, va afectar significativament a les seves propietats fisicoquímiques. Així mateix, el mètode de fabricació de les emulsions dobles va ser crucial per a la seva formació i estabilització. Així, es van obtenir emulsions dobles transportadores de clorofilina i citronela, estables durant 21 dies. D'altra banda, les nanoemulsions aplicades com recobriments antimicrobians sobre la superfície de formatge tallat, van mantenir la seva estabilitat microbiològica i van ser efectius davant de Staphylococcus aureus. La present investigació contribueix enormement al desenvolupament de les nanoestructures des del seu disseny, fins a la seva aplicació final.
Las nanoestructuras basadas en emulsiones se consideran excelentes sistemas de liberación de compuestos bioactivos de diferente naturaleza y funcionalidad. El objetivo de esta Tesis Doctoral fue estudiar los factores que afectan a la estabilidad de las nanoemulsiones y emulsiones dobles, como sistemas de encapsulación de bioactivos lipofílicos y/o hidrofílicos, respectivamente; y el efecto de su aplicación en alimentos. El tipo y la concentración de los diferentes componentes de las nanoemulsiones conteniendo curcumina o aceites esenciales, afectó significativamente a sus propiedades físico-químicas. Asimismo, el método de fabricación de las emulsiones dobles fue crucial para su formación y estabilización. Así, se obtuvieron emulsiones dobles transportadoras de clorofilina y citronela, estables durante 21 días. Por otro lado, las nanoemulsiones aplicadas como recubrimientos antimicrobianos sobre la superficie de queso cortado, mantuvieron su estabilidad microbiológica y fueron efectivos frente a Staphylococcus aureus. La presente investigación contribuye enormemente al desarrollo de nanoestructuras basadas en emulsiones, desde su diseño, hasta su aplicación final.
Emulsion-based nanostructures are considered as excellent systems for the release of bioactive compounds with different nature and functionality. The objective of this Doctoral Thesis was to study the factors that affect the stability of nanoemulsions and double emulsions, as encapsulation systems of lipophilic and/or hydrophilic bioactive compounds, respectively; and the effect of its application on food products. The type and concentration of the different components of nanoemulsions containing curcumin or essential oils, significantly affected their physicochemical properties. Also, the fabrication method and processing parametes of double emulsions was crucial for their formation and stabilization. Thus, stable double emulsions (21 days) containing chlorophyllin and citronella, were obtained. On the other hand, nanoemulsions applied as antimicrobial edible coatings onto the surface of cut-cheese, maintained their microbiological stability and were effective against Staphylococcus aureus. The present research significantly contributes to the development of nanostructures from its design to its final application.

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Shoko, Sipiwe. "Valorisation of industrial waste : extraction of bioactive compounds from Brewer’s spent grain." Thesis, Cape Peninsula University of Technology, 2018. http://hdl.handle.net/20.500.11838/2766.

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Thesis (Master of Engineering in Chemical Engineering)--Cape Peninsula University of Technology, 2018.
Brewer’s spent grain (BSG), a solid residue obtained from brewing beer, is gaining attention in the food, cosmetics and pharmaceutical industry due to its use as natural source of colorants, texturisers, functional ingredients and preservatives. It is therefore necessary to develop an economically viable method for the extraction, isolation or enrichment of these compounds. Although literature shows the technical feasibility of extraction of bioactive compounds from BSG at laboratory bench scale, none of the reviewed literature could provide adequate information necessary to determine the economic feasibility of the process at commercial scale. The aim of this study was to investigate the technical and economic viability of a commercial process for the recovery of antioxidant rich polyphenolic compounds from brewers spent grain using organic solvents and/or water. The objectives were to select the best solvent, perform the optimisation and kinetic study, as well as to model and simulate the extraction process with the aim of performing an economic analysis. In selecting the best solvent, maceration and soxhlet extraction were used for the recovery of polyphenolic compounds. Acetone and acetone: water mixtures, ethanol and ethanol: water mixtures as well as pure water were used as solvents. The evaluation of the best solvent was measured by the total phenolic content (TPC), flavonol content, the antioxidant activity using 2.2-diphenyl-1-picrylhydrazyl (DPPH) assay and ferric reducing antioxidant power (FRAP) assay. The study performed optimisation for various operational parameters (time, temperature, solvent to feed ratio and shaking speed) using response surface method. The effect of temperature on the extraction kinetics was also investigated with experiments being carried out at 20°C, 40°C and 80°C. Antioxidant activity was detected in all BSG extracts, but water showed the highest global yield and rates of extraction. The optimum conditions were found at 15 min reaction time, temperature of 40 °C, shaking speed of 185 rpm and solvent to solid ratio of 27.5: 1. So-Macdonald model was a suitable fit for the experimental data with a R2-value range of (0.85 < r2 < 0.995). A processing scenario was proposed as a base case, upon which subsequent scenarios were generated to improve the operation or the economics. SuperPro Designer® (Intelligen, Inc) was used for modelling the proposed process, for simulation and for the economic evaluation. Four alternative schemes from the base case simulation were developed for optimisation of the process. The process was found to be economically feasible and attractive with a return of investment (ROI) of 48.45 % for alternative scheme 4. The results in this thesis highlight the likely economic feasibility of the extraction of polyphenolic compounds from BSG at commercial scale by the maceration method.

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Verardo, Vito <1977&gt. "Determination of bioactive and potentially toxic compounds in food: raw material analysis and shelf life evaluation." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1521/.

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"Bioactive compounds" are extranutritional constituents that typically occur in small quantities in food. They are being intensively studied to evaluate their effects on health. Bioactive compounds include both water soluble compounds, such as phenolics, and lipidic substances such as n-3 fatty acids, tocopherols and sterols. Phenolic compounds, tocopherols and sterols are present in all plants and have been studied extensively in cereals, nuts and oil. n-3 fatty acids are present in fish and all around the vegetable kingdom. The aim of the present work was the determination of bioactive and potentially toxic compounds in cereal based foods and nuts. The first section of this study was focused on the determination of bioactive compounds in cereals. Because of that the different forms of phytosterols were investigated in hexaploid and tetraploid wheats. Hexaploid cultivars were the best source of esterified sterols (40.7% and 37.3% of total sterols for Triticum aestivum and Triticum spelta, respectively). Significant amounts of free sterols (65.5% and 60.7% of total sterols for Triticum durum and Triticum dicoccon, respectively) were found in the tetraploid cultivars. Then, free and bound phenolic compounds were identified in barley flours. HPLCESI/ MSD analysis in negative and positive ion mode established that barley free flavan-3- ols and proanthocyanidins were four dimers and four trimers having (epi)catechin and/or (epi)gallocatechin (C and/or GC) subunits. Hydroxycinnamic acids and their derivatives were the main bound phenols in barley flours. The results obtained demonstrated that barley flours were rich in phenolic compounds that showed high antioxidant activity. The study also examined the relationships between phenolic compounds and lipid oxidation of bakery. To this purpose, the investigated barley flours were used in the bakery production. The formulated oven products presented an interesting content of phenolic compounds, but they were not able to contain the lipid oxidation. Furthermore, the influence of conventional packaging on lipid oxidation of pasta was evaluated in n-3 enriched spaghetti and egg spaghetti. The results proved that conventional packaging was not appropriated to preserve pasta from lipid oxidation; in fact, pasta that was exposed to light showed a high content of potentially toxic compounds derived from lipid oxidation (such as peroxide, oxidized fatty acids and COPs). In the second section, the content of sterols, phenolic compounds, n-3 fatty acids and tocopherols in walnuts were reported. Rapid analytical techniques were used to analyze the lipid fraction and to characterize phenolic compounds in walnuts. Total lipid chromatogram was used for the simultaneous determination of the profile of sterols and tocopherols. Linoleic and linolenic acids were the most representative n-6 and n-3 essential dietary fatty acids present in these nuts. Walnuts contained substantial amounts of γ- and δ-tocopherol, which explained their antioxidant properties. Sitosterol, Δ5-avenasterol and campesterol were the major free sterols found. Capillary electrophoresis coupled to DAD and microTOF was utilized to determine phenolic content of walnut. A new compound in walnut ((2E,4E)- 8-hydroxy-2,7-dimethyl-2,4-decadiene-1,10-dioic acid 6-O-β-D-glucopiranosyl ester, [M−H]− 403.161m/z) with a structure similar to glansreginins was also identified. Phenolic compounds corresponded to 14–28% of total polar compounds quantified. Aglycone and glycosylated ellagic acid represented the principal components and account for 64–75% of total phenols in walnuts. However, the sum of glansreginins A, B and ((2E,4E)-8-hydroxy- 2,7-dimethyl-2,4-decadiene-1,10-dioic acid 6-O-β-D-glucopiranosyl ester was in the range of 72–86% of total quantified compounds.

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Cetin-Karaca, Hayriye. "ANTIMICROBIAL EFFICACY OF NATURAL BIOACTIVE COMPOUNDS AND HIGH PRESSURE PROCESSING AGAINST POTENTIAL PATHOGENS IN INFANT FOODS." UKnowledge, 2015. http://uknowledge.uky.edu/animalsci_etds/57.

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This study investigated the antimicrobial efficacy of bioactive plant compounds along with high pressure processing (HPP) against pathogens Bacillus cereus and Cronobacter sakazakii in infant formula and infant rice cereal. The influence of these applications on antimicrobial activity, shelf-life and sensory attributes of infant foods were examined. Trans-cinnamaldehyde (TC), (-)-Epigallocatechin gallate (EGCG) and [10]-Gingerol (GI) were incorporated (0.05%) in infant rice cereal reconstituted with infant formula. The cereal was inoculated with either B. cereus (ATCC 14579) or B. cereus spores (107-108 log CFU g-1). All the samples were stored at 7, 23 or 37°C for 0, 4, 8 and 24 h. TC showed the highest antimicrobial activity by inhibiting the B. cereus and its spores up to 2.72 and 3.8 log CFU g-1, respectively. HPP (600 MPa for 5 m), and TC (0.05-0.1%) along with Chitosan (CH) (1%), were applied to reconstituted powder infant formula which was inoculated with either 3 strains of C. sakazakii (ATCC 29544, ATCC 12868, and ATCC BAA 894) or 5 strains of B. cereus spore (ATCC 14579, ATCC 33018, ATCC 12826, ATCC 4342, and Difco Spores) cocktail (107-108 log CFU ml-1). All the samples were stored at 7, 23 or 45°C for 5-8 weeks. HPP and TC (0.1%) combination exhibited the highest inhibition (P < 0.05) by reducing the B. cereus spores 2.97 log CFU ml-1 after 7 d. C. sakazakii was fully inactivated by HPP, TC (0.05%) and C (1%) combination following 8 weeks of storage at 7 and 23°C and 2 weeks storage at 45°C. The combination of HPP and bioactive compounds exhibited additive antimicrobial effect. Gradual decrease (P < 0.05) in pH was observed in rice cereal and non-HPP formula samples due to the microbial growth and metabolic activity. Significant differences (P < 0.05) were found in color, aroma and general appearance of EGCG and GI applied cereal samples, while TC only did exhibit a cinnamon taste. In summary, the antimicrobial findings suggest that TC, EGCG, GI and CH could be incorporated in infant foods along with HPP as natural and safe alternatives to synthetic preservatives and thermal applications.

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Koch, Jennifer C. "Analysis of FruHis, a potential bioactive Amadori compound in processed tomatoes." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1397218276.

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OConnor, Karen. "Bioactive food ingredient acceptance of health conscious consumers in two adjoining subcouncils of the City of Cape Town." Thesis, Cape Peninsula University of Technology, 2010. http://hdl.handle.net/20.500.11838/768.

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Thesis (MTech (Consumer Science)--Cape Peninsula University of Technology, 2010
Globally, and in South Africa, consumers have become concerned about living healthier lifestyles as well as acquiring an understanding of health and using self-medication as disease preventative measures. This has resulted in an expanding consumer interest in functional foods and the non-nutrient bioactive ingredients in foods that support health. The aim of this study therefore was to determine: (i) the level of awareness, knowledge and understanding (i.e. acceptance) of functional foods and a number of bioactive food ingredients of health conscious consumers in two adjoining subcouncils of the City of Cape Town and (ii) the demographic, health and lifestyle characteristics and other socioenvironmental influences affecting their acceptance of bioactive ingredients in functional foods to describe the consumer market for functional foods and the bioactive food ingredients investigated. For the purpose of this study two groups of respondents representing the health conscious consumer were purposefully sampled. One hundred and thirty nine respondents representing the health conscious market, which includes gym subscribers and dietary supplement users, anonymously and voluntarily participated (67% response rate) from the two subcouncils, De Grendal and Blaauwberg, representing a higher economically active segment of the City of Cape Town Metropolitan Municipality.

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Giambanelli, Elisa <1983&gt. "Traditional crops and foods: documentation, analytical characterization, retention factors of bioactive compounds." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7378/.

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In recent years the interest of consumers and manufacturers on traditional foods and biodiversity has been constantly growing. The definition of traditional foods has been scientifically elaborated with different approaches, mainly based on a top-down approach. During BaSeFood, a 3 year research programme, investigations were carried out in Black sea area countries, Italy and Portugal, following a scheme of qualitative cross-cultural, on-site surveys of traditional foods and plant raw materials; the information collected has been the basis for both an extensive documentation and the selection and sampling of material to be entered in the experimental phase. A similar scheme was followed in an area of Northern Tuscany (Italy), focussing on local species and critical points in food preparation. The experimental part, was aimed at: a) evaluating the variability of local populations of the selected crops, with respect to key phytochemical compounds content; b) analyze the retention of phytochemicals following cooking/processing. Primitive wheats, mainly represented by Triticum monococcum and Triticum dicoccum, and leafy vegetables of Brassicaceae and Asteraceae families were locally collected as target species. The fate of primitive wheats phytochemicals was monitored during traditional processing of glume removal and kernel crushing, in comparison with a modern plant: besides the efficiency of the process, no relevant differences were found in bioactive compounds retention. In Brassica, retention of main phytochemical compounds was evaluated following the most common cooking methods (boiling, steaming and stir frying), also applying kinetic modelling. Retention was mainly affected by cooking method and duration, plant matrix (extractability) and the chemical nature of individual compounds. Finally, glucosinolate thermal degradation was analyzed in different binary model systems, containing broccoli, to assess the effect of added ingredients during thermal treatment. Added ingredients could play an important role on retention, however further studies are still necessary to better understand which mechanisms are involved.

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Fonseca, Daniela Filipa da Silva. "Valuation of strawberry tree fruits (Arbutus unedo L.): from chemical characterization to the development of new products." Master's thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/13924.

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Mestrado em Bioquímica - Bioquímica Alimentar
The strawberry tree (A. unedo L.) is native from the Mediterranean region and it is implanted all over the Portuguese territory. In Portugal, A. unedo fruits have been used in the production of spirit, liqueurs and jam. Considering the wide distribution through Portuguese territory and the limited number of applications, it becomes crucial to value A. unedo fruits. For this purpose it is necessary to understand the chemical composition of A. unedo fruits, particularly during maturation and storage. Therefore, some quality parameters of A. unedo fruits were studied throughout maturation, particularly ºBrix, pH, titratable acidity, total phenolic content and antioxidant activity. In addition, the lipophilic extractives profile was assessed in ripen fruits. To promote the consumption of A. unedo fresh fruits it was studied the effect of cold storage (≈ 5 ºC) using fruits from two different ripeness degrees (19 and 21 ºBrix). The final phase of this thesis was focused on innovation and development of new food products based on A. unedo fruits. This study allowed us to conclude that throughout maturation, the ºBrix content and pH increased, whereas titratable acidity, total phenolic content and the antioxidant activity exhibited no remarkable tendency. Moreover, 41 lipophilic compounds were identified in A. unedo fruits, which belong to 5 chemical families: triterpenoids, fatty acids, sterols, tocopherols and long chain aliphatic alcohols. Triterpenoids represent the major group of identified compounds, (ca. of 70 % of the total amount after alkaline hydrolysis), accounting for between 3196-5494 mg.kg-1 dry weight (dw)). Sterols account for between 217-805 mg.kg-1 dw and fatty acids content varies between 587-2954 mg.kg-1 dw (of which 50 to 78 % corresponded to unsaturated fatty acids). Tocopherols content range between 21-115 mg.kg-1 dw and the long-chain aliphatic alcohols are present in a broader range of 30-453 mg.kg-1 dw. Regarding the effect of cold storage using fruits from two different ripeness degrees, this study shows that the ripen-harvested fruits (21 ºBrix) can be stored up to 17 days while the unripen-harvested fruits (19 ºBrix) can be stored up to 20 days. At the best eating-point, berries from both sampling moments presented similar sensory and chemical characteristics. However, the unripen-harvested fruits were less pasty in the mouth and had significantly lower levels of ethanol. These results suggest that the fruits harvested with ca. of 19 ºBrix, pH 2.7 and titratable acidity of 1 g malic acid per 100 g fresh fruit, contribute to increase their shelf-life while maintaining the firmness and reduced ethanol content. The final phase of this thesis included several stages, namely research on consumer habits of A. unedo fruits by the Portuguese population, the assessment of market opportunities for this type of product, and the design of some novel products that are in line with current market trends. Thus, they were conceived and tested over several formulations of cookies, yoghurts, cereal bars and chocolates. In conclusion, the results obtained are relevant regarding the general chemical characterization of the Serra da Beira region strawberry tree fruits, with emphasis to the lipophilic compounds. The presence of the compounds with reported health benefits, particularly ω-3 and ω-6 fatty acids, phytosterols and triterpenoids, can be a crucial factor on the valuation of A. unedo fruits. Assessing the impact of maturation and cold storage on fresh fruits can be used as a decision tool to support A. unedo fruits producers, in order to reach new consumers and new markets. The last phase of this work also confirms that this fruit has numerous applications in the food area, which are in line with the current market trends.
O medronheiro (Arbutus unedo L.) é uma planta nativa da região Mediterrânica e está presente em todo o território nacional. Em Portugal, o medronho é utilizado maioritariamente na produção de aguardente, licores e compota. Considerando a extensa distribuição do medronho pelo território português e o reduzido número de aplicações, torna-se imperativo valorizar este fruto. Para tal é necessário conhecer a sua composição química e as modificações que ocorrem ao longo do amadurecimento e do armazenamento. Assim, foram estudados alguns parâmetros de qualidade do medronho ao longo da maturação, nomeadamente, o ºBrix, pH, acidez titulável, o conteúdo em fenóis totais e a atividade antioxidante. Paralelamente, foi estabelecido o perfil de compostos lipofílicos do fruto maduro. Com vista a promover o consumo do medronho em fresco foi avaliado o efeito da conservação em frio (≈5ºC) de frutos colhidos em diferentes graus de maturação (≈19 e 21 ºBrix). A fase final desta tese foi focada na inovação e desenvolvimento de novos produtos alimentares com base no uso do medronho. Ao longo da maturação, observou-se um aumento do ºBrix e do pH, enquanto que a acidez titutável, o conteúdo em fenóis totais e a atividade antioxidante não mostraram nenhuma tendência assinalável. O perfil lipofílico do medronho maduro compreende 41 compostos pertencentes a 5 famílias: triterpenóides, ácidos gordos, esteróis, tocoferóis e álcoois alifáticos de cadeia longa. Os triterpenóides são o grupo maioritário (até 70 % da massa total de extrato após a hidrólise alcalina), com teores entre 3196 a 5494 mg.kg-1 peso seco (ps). O conteúdo em fitoesteróis varia entre 217 e 805 mg.kg-1 ps e o conteúdo em ácidos gordos varia entre 587 e 2954 mg.kg-1 ps, dos quais ca. de 50 a 78 % correspondem a ácidos gordos insaturados. O conteúdo em tocoferóis varia entre 21 e 115 mg.kg-1 ps e os álcoois gordos de cadeia longa entre 30 e 453 mg.kg-1 ps. O estudo do efeito da conservação do fruto fresco em frio permitiu concluir que o medronho colhido com 21 ºBrix pode ser armazenado até 17 dias enquanto o fruto colhido com 19 ºBrix pode ser armazenado até 20 dias. Na fase ótima de consumo, os frutos colhidos em diferentes estado de maturação apresentam características sensoriais e químicas similares, sendo de realçar que os frutos colhidos em estado de maturação precoce são menos pastosos na boca e apresentam teores significativamente menores de etanol. Estes resultados sugerem que a colheita de frutos com ca. 19º Brix, pH 2.7 e acidez titulável de 1 g ácido málico por 100 g de fruto fresco, contribuem para o aumento do tempo de prateleira, mantendo a firmeza do fruto e um reduzido teor de etanol. A fase final desta tese incluiu várias etapas, nomeadamente, a pesquisa sobre hábitos de consumo de medronho pela população portuguesa, a avaliação das oportunidades de mercado para este tipo de produto, e a conceção de alguns produtos que estivessem em linha com as atuais tendências de mercado. Assim, foram concebidos e testadas várias formulações de bolachas, iogurtes, barras de cereais e bombons. Em conclusão, os resultados obtidos são relevantes no que diz respeito à caracterização química sumária do medronho da região da Beira Serra, com especial destaque para os compostos lipofílicos. A presença de compostos com reconhecidos efeitos benéficos para a saúde humana, nomeadamente os ácidos gordos ω-3 e ω-6, fitoesteróis e os triterpenóides, pode ser um fator determinante para a valorização do medronho. A avaliação do impacto da maturação e da conservação em frio sobre os frutos frescos podem ser usados como uma ferramenta de suporte à decisão por produtores de medronho, com vista a atingir novos consumidores e novos mercados. A fase final do trabalho, também permite confirmar que este produto tem inúmeras aplicações na área alimentar, as quais estão em linha com as actuais tendências de mercado.

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Candéa, Tatiana Vidal. "Study of membrane emulsification process as a pre-step for the microencapsulation of lipid compounds by spray drying." Master's thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/10412.

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Dissertation presented to Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa for obtaining the master degree in Membrane Engineering
Food emulsions play an important role in product development and formulation, as well as to encapsulation of food additives. Conventional methods for emulsion production may present some drawbacks, such as the use of high shear stress, high energy demanding and polydisperse droplet size distribution. In this sense, membrane emulsification emerges as an alternative method to overcome all this issues and to produce fine and stable emulsions. Linseed oil has been widely studied in the last years, due to its nutritional composition, being the richest ω-3 vegetable source and for that reason it was used as the raw material for emulsion production. Premix and direct (cross flow) membrane emulsification were carried out using three different membrane materials: polissulphone, cellulose ester and α-alumina membrane. For premix membrane emulsification (PME) the variables transmembrane pressure, membrane material, surfactant type and membrane mean pore size were evaluated. The membrane mean pore size was the crucial factor to achieve emulsions by PME, once it was not possible to achieve stable emulsion with mean pore sizes lower than 0.8 μm. For direct membrane emulsification, transmembrane pressure, surfactant concentration and cross flow velocity were evaluated by means of a experimental design. The evaluated responses were stability, droplet size and distribution and dispersed phase flux. For all the variables studied, only dispersed phase flux showed to have significant influence of pressure. Comparing both methods of membrane emulsification, premix showed to be more suitable in terms of emulsion production throughput and droplet size correlation with membrane pore size, however, in terms of stability, direct membrane emulsification showed much better results. Encapsulation of linseed oil by spray drying was promoted using the optimum point of the performed experimental design and the droplets size distribution has considerably changed with the addition of the wall material to the emulsion.
The EM3E Master is an Education Programme supported by the European Commission, the European Membrane Society (EMS), the European Membrane House (EMH), and a large international network of industrial companies, research centres and universities

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Almeida, Mariana Corrêa de. "Efeitos do processamento por radiação em espécies da família Zingiberaceae: açafrão (Curcuma longa L.), gengibre (Zingiber officinale Roscoe) e zedoária (Curcuma zedoaria (Christm.) Roscoe)." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-03042012-100652/.

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As espécies da família Zingiberaceae são caracterizadas por suas raízes. Constituintes fenóis como curcuminóides e gingeróis destacam-se por suas atividades biológicas. A irradiação de alimentos é um meio de preservação eficiente, porém, é importante garantir que suas propriedades funcionais sejam preservadas. Este trabalho vem avaliar o efeito do processamento por radiação gama de 60Co em doses de 0, 5, 10, 15 e 20kGy sobre espécies de Zingiberaceae: açafrão (Curcuma longa L.), gengibre (Zingiber officinale Roscoe) e zedoária (Curcuma zedoaria (Christm.) Roscoe). A determinação qualitativa do perfil de compostos bioativos foi realizada por cromatografia de camada delgada. A quantificação de compostos fenólicos foi realizada pelo método Folin-Ciocalteu e a avaliação do potencial da atividade antioxidante pelo teste de captação do radical livre [2,2 difenil-1-pricril-hidrazil (DPPH)] e método Rancimat®. A quantificação de curcumina e 6-gingerol foram realizadas por Cromatografia Líquida de Alta Eficiência. Não houve mudança no perfil fitoquímico das espécies após o tratamento por irradiação. Em relação às amostras controle, houve perdas significativas no teor de compostos fenólicos nas amostras de açafrão nas doses de 15kGy e 20kGy. Ocorreu decréscimo significativo da capacidade de captação do DPPH nos extratos de gengibre irradiados e no extrato de zedoária irradiado com 20kGy. O Índice de Atividade Antioxidante foi significativamente menor nos extratos de açafrão irradiados com 5kGy e 15kGy e nos extratos irradiados de zedoária. A quantificação de curcumina foi significativamente menor nos extratos de açafrão irradiados com 15 kGy e não houve diferença significativa na quantificação de 6-gingerol entre os extratos de gengibre. Conclui-se que a tecnologia de processamento de Zingiberaceae por radiação gama pode ser viável para as indústrias. Para segurança da manutenção da atividade antioxidante as doses devem ser de até 10kGy.
The species of Zingiberaceae family are characterized for rhizome. Phenolic constituents like curcuminoids and gingerols have had reports of biological activities. Food irradiation is an effective means of preservation, however it is important to ensure that their functional properties are not compromised. The aim of this study was to evaluate the effectiveness of gamma radiation from 60Co in doses of 0, 5, 10, 15 and 20 kGy on species of Zingiberaceae: turmeric (Curcuma longa L.), ginger (Zingiber officinale Roscoe) and zedoaria (Curcuma zedoaria (Christm.) Roscoe). The qualitative determination of bioactive compounds profile was performed by thin layer chromatography. The quantification of phenolic compounds was performed by Folin-Ciocalteu method and assessing the potential of antioxidant activity by the free radical [2,2 difenil-1-pricril-hidrazil (DPPH)] scavenging and by Rancimat® method. The curcumin and 6-gingerol quantification was performed by High Performance Liquid Chromatography. Compared to control, there were significant losses of total phenolic compounds in turmeric samples irradiated with 15kGy and 20kGy. There were significant decreases in the ability to scavenge DPPH in irradiated ginger extracts and zedoaria extract irradiated with 20kGy. The Antioxidant Activity Index was significantly lower in 5kGy and 15kGy irradiated turmeric extracts and in irradiated zedoaria extracts. The curcumin quantification was significantly lower in 15kGy irradiated turmeric extracts and there was no significant difference in the 6-gingerol quantification between ginger extracts. It is concluded that gamma radiation processing technology in Zingiberaceae can be viable for industry. To maintain safety of antioxidant activity it should be applied doses up 10kGy.

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Duarte, Renato César. "Estudo dos compostos bioativos em especiarias (Syzygium aromaticum L, Cinnamomum zeylanicum Blume e Myristica fragans Houtt) processadas por radiação ionizante." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-12022015-142658/.

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As especiarias e as ervas aromáticas se apresentam na forma de folhas, flores, gomos, sementes, cascas ou rizomas secos de diferentes plantas. Podemos defini-las como produtos de origem vegetal aromatizados que se volatilizam com facilidade quando incorporados em pequena quantidade aos produtos alimentares, e contribuem para o seu aroma, sabor e cor ou ainda para sua conservação. Atualmente as pessoas procuram as especiarias por suas propriedades funcionais, compostos bioativos e qualidades sensoriais. Um grande problema é a redução da quantidade destes compostos durante toda a cadeia produtiva, a partir da colheita, processamento, armazenamento e distribuição. Há muito tempo, pesquisadores e indústrias estão concentrados no aprimoramento dos processos na cadeia produtiva, buscando garantir a segurança sanitária e alimentar, a conservação dos alimentos por mais tempo e o aumento de sua vida útil, sem alterar, de forma drástica, suas propriedades. Devido às produções artesanais e à falta do cumprimento das boas práticas em sua cadeia produtiva, as especiarias podem conter alta carga microbiológica, acarretando sérias complicações à saúde do consumidor. Para diminuir esses problemas, frequentemente é utilizado o processamento por radiação. Com o exposto, os objetivos deste trabalho foram: Analisar as propriedades antifúngicas dos óleos das especiarias irradiadas com doses médias (2,5; 5; 7,5 e 10 kGy); Estudar os efeitos de doses médias (5 e 10 kGy) e altas (20 e 30 kGy) de radiação gama de 60Co nos compostos bioativos das especiarias - cravo, canela e noz-moscada; Identificar os compostos dos óleos; Identificar o compostos voláteis no headspace dos óleos e das especiarias in natura; Identificar os compostos da parte não volátil da noz-moscada e Identificar os compostos quirais da canela. Ao comparar as amostras controle (não irradiadas) com as processadas nas doses descritas, em relação às propriedades antifúngicas dos óleos, foi possível verificar a eficácia e posteriormente que a irradiação não interferiu em sua eficiência; Em relação aos demais testes deste trabalho, os compostos foram identificados e na maioria dos testes o processo de irradiação não interferiu de forma significativa na quantidade dos compostos.
Spices and aromatic herbs are divided into leaves, flowers, bud, seeds bark or dry roots from different plants and it is possible to define them as products of highly flavored vegetal origin that volatize easily when incorporated in small quantities to food products and contribute to its aroma, flavor, color or even to its preservation. Nowadays, people look for its functional properties, bioactive compounds and sensory qualities. A big problem is the reduction of the quantity of these compounds throughout the production chain from the harvest process, storage and distribution. For a long time researchers and industries have concentrated on perfecting the processes of the production chain seeking to guarantee the sanitary and food safety, preserving foodstuffs for a long period and an increase in its lifespan without drastically altering its properties. Due to homemade products and the lack of compliance with good practices in its production chain, the spices can contain a high amount of microbiology causing serious complications to the health of the consumer and the radiation processing is often used for reduce these problems. With this finding, the objectives of this work were: Analyze the oil antifungal properties of spices irradiated with average doses (2.5; 5; 7.5 and 10 kGy); Study the average doses (5 and 10 kGy) and high dose (20 and 30 kGy) effects of gamma radiation 60Co in the bioactive compounds of the spices - cloves, cinnamon and nutmeg; Identify the oils compounds; Identify the volatile compounds in the headspace of the oils and the in natura spices. Identify the compounds of the nonvolatile part of the nutmeg; Identify the chiral compounds of the cinnamon. Comparing the control samples (not irradiated) with the processed at the described doses, regarding the oil antifungal properties it was possible to verify the efficiency and later that the irradiation did not interfered in its efficiency; Regarding to the others tests in this work, the compounds were identified and most of the tests the irradiation did not interfere significantly with the compounds amount.

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Borglin, Matthew R. "Analysis of Biofilm Remediation Capacity For Octenyl Succinic Anhydride (OSA), A Bioactive Food Starch Modifier Compound." DigitalCommons@CalPoly, 2020. https://digitalcommons.calpoly.edu/theses/2168.

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Matthew R. Borglin This thesis demonstrates efficacy of Octenyl Succinic Anhydride (OSA), as a biofilm sanitizer. Biofilms allow bacteria to adhere to solid surfaces with the use of excreted polymeric compounds. For example, surfaces found in food production or processing facilities such as the interior of a raw milk holding tank, are some of the most susceptible to biofilm contamination. When present, biofilms can cause a variety of negative effects, which include; reduction of product shelf life, corrosion, and outbreaks of foodborne illnesses. The close association of biofilms with the majority of foodborne illness cases led the US Environmental Protection Agency (EPA) to create a new category of sanitizer specifically designed for treatment of mature biofilms. The efficacy of sanitizers in this new regulatory category is determined by the EPA protocols MB-19 and MB-20. The EPA’s protocols outline methods for cultivating, treating, and measuring effects on Pseudomonas aeruginosa biofilms in a continuous flow stir bar bioreactor. Biofilm modification by OSA was verified by the presence of octenyl esters on OSA treated biofilms with single point Raman spectrophotometry. OSA modified biofilm’s antimicrobial properties were first investigated with crystal violet staining in 96-well microtiter plates with inconclusive results. However, effective antimicrobial properties where apparent when using the CDC Biofilm Reactor. OSA treatments consistently returned a 6-log CFU/coupon reduction in biomass compared to controls. Inhibition of planktonic and/or biofilm regrowth was demonstrated using the 96-well plate methodology. This thesis demonstrated the effectiveness of OSA chemical esterification reaction as a biofilm treatment. In doing so, this work suggests a new approach for biofilm remediation by chemically modifying the structural components of biofilm.

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Taneyo, Saa Danielle Laure <1984&gt. "Use of Biotechnology to increase the content of bioactive compounds in fermented foods of plant origin." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6433/.

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The objectives of this PhD research were: i) to evaluate the use of bread making process to increase the content of β-glucans, resistant starch, fructans, dietary fibers and phenolic compounds of kamut khorasan and wheat breads made with flours obtained from kernels at different maturation stage (at milky stage and fully ripe) and ii) to study the impact of whole grains consumption in the human gut. The fermentation and the stages of kernel development or maturation had a great impact on the amount of resistant starch, fructans and β-glucans as well as their interactions resulted highly statistically significant. The amount of fructans was high in kamut bread (2.1g/100g) at the fully ripe stage compared to wheat during industrial fermentation (baker’s yeast). The sourdough increases the content of polyphenols more than industrial fermentation especially in bread made by flour at milky stage. From the analysis of volatile compounds it resulted that the sensors of electronic nose perceived more aromatic compound in kamut products, as well as the SPME-GC-MS, thus we can assume that kamut is more aromatic than wheat, so using it in sourdough process can be a successful approach to improve the bread taste and flavor. The determination of whole grain biormakers such as alkylresorcinols and others using FIE-MS AND GC-tof-MS is a valuable alternative for further metabolic investigations. The decrease of N-acetyl-glucosamine and 3-methyl-hexanedioic acid in kamut faecal samples suggests that kamut can have a role in modulating mucus production/degradation or even gut inflammation. This work gives a new approach to the innovation strategies in bakery functional foods, that can help to choose the right or best combination between stages of kernel maturation-fermentation process and baking temperature.

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Somavat, Romel. "Applications and Effects of Ohmic Heating: Sterilization, Influence on Bacterial Spores, Enzymes, Bioactive Components and Quality Factors in Food." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1293568724.

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21

Hirashima, Fabiana Kawassaki. "Efeito da radiação gama nas propriedades nutricionais e bioativas de alimentos minimamente processados destinados a dietas especiais." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-25042018-151920/.

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A nutrição possui papel de fundamental importância na promoção da saúde. Os alimentos in natura podem ser encontrados na forma de frutas e vegetais minimamente processados (fresh-cut) embalados. Uma alternativa para a administração de alguns alimentos in natura aos indivíduos imunocomprometidos e neutropênicos, ou até mesmo para a população em geral, é a aplicação de radiação gama, em doses sub-esterilizantes, com o intuito de oferecer alimentos de qualidade e seguros do ponto de vista microbiológico. A descrição na literatura sobre tentativas de oferecer alimentos seguros e saudáveis aos indivíduos portadores de patologias do sistema imune é escassa. Assim, o objetivo do trabalho foi avaliar o efeito de diferentes doses de radiação gama na composição química, no teor de compostos bioativos e atividade antioxidante de abacaxi, salada de frutas, mini cenouras e salada de folhas minimamente processados destinados a dietas especiais. As amostras foram submetidas à radiação gama, com doses de 0.5, 1, 2 e 3 kGy e analisadas juntamente com as amostras controle (não irradiadas). Foram analisados a composição centesimal, compostos fenólicos, flavonóides, proantocianidinas, atividade antioxidante por ORAC e DPPH•, vitamina C e carotenóides. Não foram observadas alterações significativas nos compostos avaliados antes e após a irradiação, com exceção dos carotenóides que demonstraram um aumento significativo dos teores após a aplicação de radiação gama. Assim, pode-se concluir que a irradiação, aplicada em baixas doses e em alimentos minimamente processados, promove a manutenção do valor nutricional do alimento, trazendo benefícios aos indivíduos que necessitam de alimentos seguros e de suficiente aporte nutricional que garanta a promoção e recuperação da saúde, tais como os imunocomprometidos.
Nutrition plays a fundamental role in promoting health. The fresh food can be found in form of minimally processed fruits and vegetables (fresh-cut). An alternative of fresh food administration to immunocompromised and neutropenic individuals, or even to the general population, is the application of gamma radiation in sub-sterilizing doses, in order to provide quality and safe food in microbiological point of view. The description in the literature on attempts to provide safe and healthy food to individuals with immune system disorders is scarce. The objective of the study was to evaluate the effect of different doses of gamma radiation in the chemical composition, the bioactive compounds content and antioxidant activity of minimally processed pineapple, fruit salad, mini carrots and leaves salad for special diets. Samples were subjected to gamma radiation doses of 0.5, 1, 2 to 3 kGy and analyzed at the same time with control samples (not irradiated). There were analyzed the chemical composition, phenolic compounds, flavonoids, proanthocyanidins, antioxidant activity by ORAC and DPPH•, vitamin C and carotenoids. No significant changes were observed in compounds contents before and after irradiation, except carotenoids that have demonstrated a significant increase in levels after application of gamma radiation. Thus, it can be concluded that irradiation applied in low doses and in minimally processed foods promotes the maintenance of food nutritional value, bringing benefits to the individuals who need safe food and adequate nutritional supply to ensure the promotion and recovery health, such as immunocompromised.

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22

Sánchez, Vega Rogelio. "Effects of high-intensity pulsed electric fields on the bioactive compounds stability and enzymes of broccoli juice." Doctoral thesis, Universitat de Lleida, 2016. http://hdl.handle.net/10803/383050.

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This thesis doctoral was focused on evaluating the influence of HIPEF-processing parameters (electric field strength, treatment time and polarity) on bioactive compounds (chlorophylls, carotenoids, vitamin C and total phenolic compounds), minerals, amino acids and enzymes (myrosinase, polyphenol oxidase and lipoxygenase) of broccoli juice. Results of HIPEF-processed broccoli juice were compared with those of thermally treated (90 °C/60 s) and untreated juices. The HIPEF processing parameters significantly influenced the relative content (RC) of lutein, β-carotene, total phenolics (TP), vitamin C, minerals and amino acids, relative antioxidant capacity, as well as the RC of chlorophylls degradation compounds, the enzymes chlorophyllase, polyphenol oxidase, lipoxygenase and color difference (ΔE). However, polarity did not exert influence neither on Chl a, Chl b nor on ΔE. HIPEF-treated broccoli juice exhibited superior content of chlorophylls, carotenoids, TP, vitamin C, minerals, amino acids, and antioxidant capacity than those thermally treated or untreated juice. Also, the highest ΔE (7.89) was observed in the broccoli juice processed by heat.
La presente tesis doctoral se centro en evaluar la influencia de los paramétros de procesamiento de HIPEF (intensidad de campo eléctrico, tiempo de tratamiento y polaridad) sobre los compuestos bioactivos (clorofilas, carotenoides, vitamina C y compuestos fenólicos totales), minerales, aminoácidos y enzimas (mirosinasa, polifenol oxidasa y lipoxigenasa) de zumo de brócoli. Los resultados del zumo de brócoli procesado con HIPEF fueron comparados con aquellos del zumo tratado térmicamente (90 °C/60 s) y del zumo sin procesar. Las parámetros de procesamiento con HIPEF influyó significativamente sobre el contenido relativo (RC) de luteína, β-caroteno, fenoles totales (TP), vitamina C, minerales y aminoácidos, capacidad antioxidante relativa, así como el RC de compuestos de degradación de clorofila, las enzimas clorofilasa, polifenol oxidasa, lipoxigenasa y diferencia de color (ΔE). Sin embargo, la polaridad no tuvo influencia sobre Chl a, Chl b ni sobre ΔE. El zumo de brócoli tratado con HIPEF mostró un mayor contenido de clorofilas, carotenoides, TP, vitamina C, minerales, aminoácids, y capacidad antioxidante que aquellos procesados térmicamente y sin tratar. Además, la ΔE más elevada (7.89) fue observada en el zumo de brócoli procesado con calor.
La present tesi doctoral es va centrar en avaluar la influència dels paràmetres de processament de HIPEF (intensitat de camp elèctric, temps de tractament i polaritat) sobre els compostos bioactius (clorofil•les, carotenoides, vitamina C i compostos fenòlics totals), minerals, aminoàcids i enzims (mirosinasa, polifenol oxidasa i lipoxigenasa) de suc de bròquil. Els resultats del suc de bròquil processat amb HIPEF van ser comparats amb aquells del suc tractat tèrmicament (90 °C/60 s) i del suc sense processar. Les paràmetres de processament amb HIPEF va influir significativament sobre el contingut relatiu (RC) de luteïna, β-carotè, fenols totals (TP), vitamina C, minerals i aminoàcids, capacitat antioxidant relativa, així com el RC de compostos de degradació de clorofil•la, els enzims clorofilasa, polifenol oxidasa, lipoxigenasa i diferència de color (ΔE). No obstant això, la polaritat no va tenir influència sobre Chl a, Chl b ni sobre ΔE. El suc de bròquil tractat amb HIPEF va mostrar un major contingut de clorofil•les, carotenoides, TP, vitamina C, minerals, aminoácids, i capacitat antioxidant que aquells processats tèrmicament i sense tractar. A més, la ΔE més elevada (7.89) va ser observada en el suc de bròquil processat amb calor.

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Chen, Xi. "Functional food-related bioactive compounds: effect of sorghum phenolics on cancer cells in vivo and conversion of short- to long-chain omega-3 polyunsaturated fatty acids in duck liver in vivo." Diss., Kansas State University, 2017. http://hdl.handle.net/2097/38244.

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Doctor of Philosophy
Department of Human Nutrition
Weiqun Wang
Many functional food related bioactive compounds have been discovered and draw the attention of scientists. This dissertation focused on sorghum phenolic compounds and omega-3 polyunsaturated fatty acids. Study 1: phenolic agents in plant foods have been associated with chronic disease prevention, especially cancer. However, a direct evidence and the underlying mechanisms are mostly unknown. This study selected 13 sorghum accessions and was aim to investigate: (1) the effect of extracted sorghum phenolics on inhibiting cancer cell growth using hepatocarcinoma HepG2 and colorectal adenocarcinoma Caco-2 cell lines; (2) and the underlying mechanisms regarding cytotoxicity, cell cycle interruption, and apoptosis induction. Treatment of HepG2 and Caco-2 cells with the extracted phenolics at 0-200 M GAE (Gallic acid equivalent) up to 72 hrs resulted in a dose- and time-dependent reduction in cell number. The underlying mechanism of cell growth inhibition was examined by flow cytometry, significant inverse correlations were observed between the decreased cell number and increased cell cycle arrest at G2/M or induced apoptosis cells in both HepG2 and Caco-2 cells. The cytotoxic assay showed that the sorghum phenolic extracts were non-toxic. Although it was less sensitive, a similar inhibitory impact and underlying mechanisms were found in Caco-2 cells. These results indicated for the 1st time that a direct inhibition of either HepG2 or Caco-2 cell growth by phenolic extracts from13 selected sorghum accessions was due to cytostatic and apoptotic but not cytotoxic mechanisms. In addition, these findings suggested that sorghum be a valuable functional food by providing sustainable phenolics for potential cancer prevention. Study 2: omega-3 polyunsaturated fatty acids (ω-3 PUFAs) especially long-chain ω-3 PUFAs, have been associated with potential health benefits in chronic disease prevention. However, the conversion rate from short- to long-chain ω-3 PUFAs is limited in human body. This study was aim to assess the modification of fatty acid profiles as well as investigate the conversion of short- to long-chain ω-3 PUFAs in the liver of Shan Partridge duck after feeding various dietary fats. The experimental diets substituted the basal diet by 2% of flaxseed oil, rapeseed oil, beef tallow, or fish oil, respectively. As expected, the total ω-3 fatty acids and the ratio of total ω-3/ ω-6 significantly increased in both flaxseed and fish oil groups when compared with the control diet. No significant change of total saturated fatty acids or ω-3 fatty acids was found in both rapeseed and beef tallow groups. Short-chain ω-3 α-linolenic acid (ALA) in flaxseed oil-fed group was efficiently converted to long-chain ω-3 docosahexaenoic acid (DHA) in the duck liver. This study showed the fatty acid profiling in the duck liver after various dietary fat consumption, provided insight into a dose response change of ω-3 fatty acids, indicated an efficient conversion of short- to long-chain ω-3 fatty acid, and suggested alternative long-chain ω-3 fatty acid-enriched duck products for human health benefits. In conclusion, the two studies in this dissertation provided a fundamental understanding of anti-cancer activity by sorghum phenolic extracts and the conversion of short- to long-chain ω-3 PUFAs in duck liver, contribute to a long term goal of promoting sorghum and duck as sustainable phenolic and ω-3 PUFAs sources as well as healthy food products for human beings.

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24

Clark, Kathryn. "Marine chemical ecology: the search for sequestered and bioactive compounds in the sea hares «dolabrifera dolabrifera» and «stylocheilus striatus» and in their preferred food, the cyanobacterium, «lyngbya majuscula»." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=19264.

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Dolabrifera dolabrifera, an anaspidean mollusc (sea hare) collected from Panama's Coiba National Park, was subjected to its first marine chemical ecology study. Its digestive gland contained 5a,8a-epidioxycholest-6-en-3ß-ol. This compound, documented for the first time in D. dolabrifera, demonstrated activity against the parasite responsible for leishmania (Leishmania donovani). An evaluation of its dietary repertoire revealed that D. dolabrifera significantly preferred the cyanobacterium Lyngbya majuscula over cyanobacterium Symploca sp., green alga Chaetomorpha sp., and red alga Spyridia sp.. A no-choice feeding assay using L. majuscula or green alga Cladophora sp. confirmed this preference. Through bioassay-guided fractionation, two novel cyanobacterial peptides were isolated. These compounds were determined active against Plasmodium falciparum, with one compound also active against L. donovani. These peptides were sequestered by sea hare Stylocheilus striatus, but not by D. dolabrifera. This work suggests that chemical ecological studies involving sea hares and cyanobacteria can guide researchers to compounds active against tropical parasites.
Des opisthobranches (anaspidea) dont une espèce nommé Dolabrifera dolabrifera a été étudié au Parc National Coiba, une île au Panama. Cette étude de chimie écologique marine est la première pour cette espèce. Dans sa glande digestive, on a retrouvé 5a,8a-épidioxycholest-6-en-3ß-ol. Ce composé possède des nouvelles activités contre le parasite de leishmanioses (Leishmania donovani). Lors d'une expérience d'alimentation D. dolabrifera a préféré la cyanobactérie Lyngbya majuscula, plutôt qu'une algue verte Chaetomorpha, une algue rouge Spyridia et une cyanobactérie Symploca. L'expérience suivante d'alimentation D. dolabrifera a mangé L. majuscula plutôt qu'une algue verte Cladophora. Deux peptides nouveaux étaient isolés de la L. majuscula, les deux actives en malaria (Plasmodium falciparum). Aussi un peptide actif en leishmanioses (L. donovani) et l'autre en malaria (P. falciparum). Ces composés étaient séquestrés dans un opisthobranche appelé Stylocheilus striatus. Ce travail suggère des études en chimie écologie chez les opisthobranches et les cyanobactéries qui peuvent amener à des composés ayant des activités contre les parasités tropicales.

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PEREIRA, Neusa Lygia Vilarim. "Concentração de àcido siálico em soro de queijo caprino resultante do processo de coagulação láctea enzimática e mista." Universidade Federal de Pernambuco, 2016. https://repositorio.ufpe.br/handle/123456789/18054.

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CNPq
O ácido siálico está presente nos leites na forma de ácido N-acetilneuramínico (Neu5Ac) e ácido N-glicolilneuramínico (Neu5Gc), desempenhando uma série de benefícios à saúde humana. O soro de queijo caprino é um bioproduto da fração solúvel do leite, obtido através da coagulação da caseína. É considerado importante para a indústria de alimentos, como ingrediente, sendo responsável por 55% de todos os nutrientes do leite. Neste estudo, objetivouse quantificar, pela primeira vez na literatura, o ácido siálico presente naturalmente no soro de queijo caprino por diferentes processos de coagulação láctea. O leite utilizado foi obtido de cabras da raça Saanen e submetidos ao processamento de coagulação enzimático e misto (enzima + cultura starter) para obtenção do soro, que foi acondicionado e congelado, sendo parte liofilizado. A identificação e quantificação do ácido siálico foi realizada por Cromatografia Líquida de Alta Eficiência por detector de fluorescência modelo RF-20A. A concentração desse nutriente variou de 23,5 a 292,1 mg/L. Foi verificado que a coagulação enzimática preserva o ácido siálico (Neu5Gc e Neu5Ac) mais eficientemente do que a coagulação mista, pois as bactérias da cultura starter possibilitaram a redução dos nutrientes presentes no soro para desempenharem o seu metabolismo, assim o ácido siálico presente como glicoconjugado, também foi reduzido. De acordo com os resultados obtidos, pode-se concluir que o soro de queijo caprino apresenta um potencial funcional, visto que contém uma quantidade relevante do nutriente estudado.
Sialic acid is present in milk in the form of N-acetylneuraminic acid (Neu5Ac) and Nglycolylneuraminic acid (Neu5Gc), performing a lot of benefits to human health. Goat cheese whey is a dairy byproduct from the soluble fraction obtained by casein coagulation. It is considered important for the food industry, as an ingredient, accounting for 55% of all milk nutrients. This study aimed to quantify the sialic acid present naturally in the goat cheese whey by different milk coagulation processes. The milk was obtained from Saanen goats and subjected to processing enzymatic and mixed coagulation (enzyme + starter culture) to obtain the whey, which was prepared and frozen, and part of it was lyophilized. The identification and quantitation of sialic acid was accomplished by High Performance Liquid Chromatography fluorescence detector RF-20A model. The sialic acid concentration ranged from 23.5 to 292.1 mg / L. It has been found that enzimatic coagulation preserves the sialic acid (Neu5Ac and Neu5Gc) more efficiently than mixed coagulation, because the bacterias of starter culture allowed the reduction of nutrients present in the whey to perform their metabolism, as well sialic acid present as glycoconjugate it was also reduced. According to the results, concluded that goat cheese whey has a functional potential, since it contains a significant quantity of the nutrient studied.

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Maslonková, Ivana. "Vliv vybraných superpotravin a jejich složek na lidské buňky." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2018. http://www.nusl.cz/ntk/nusl-376784.

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The presented diploma thesis is focused on the study of composition and biological effects of some super-foods. Theoretical part deals with basic information about chosen superfoods and their bioactive substances. Further, theoretical part describes the overview of vesicular systems used for encapsulation and the most common methods of particle characterization. A brief review of cell cultures and cultivation of human cells is presented as well as methods for cytotoxicity a genotoxicity testing. In the experimental section, aqueous and ethanol extracts of super-foods were prepared. These extracts were then encapsulated into liposomal and combined PHB particles. Super-food extracts were characterized by spectrophotometrical methods in order to determine the content of polyphenols, flavonoids, anthocyanins, carotenes, chlorophyll, tannins, and antioxidant activity. The physico-chemical characteristics of prepared liposomal and combined particles were determined too. The particles with encapsulated extracts were further tested using the MTT assay and SOS chromotest to describe their potential cytotoxic and genotoxic effects.

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Khalaf, Eyada. "Phenolic-Linked Antioxidant and Anti-Hyperglycemic Properties of Selected Cereal, Pseudo-Cereal, and Millet Using In Vitro Screening Methods." Thesis, North Dakota State University, 2018. https://hdl.handle.net/10365/29281.

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Improving diversity of food systems by targeting whole grain cereals, pseudo-cereals, and millets is essential to enhance nutritional qualities beyond macro and micronutrient balance and to address emerging global food and nutritional security-linked public health challenges. However, human health relevant nutritional parameters of whole grains vary widely among species, genotypes, growing conditions, and further due to different processing methods. Therefore, it is important to screen human health relevant nutritional parameters of these whole grains prior to targeting them for wider public health solutions linked to non-communicable chronic diseases (NCD). Based on this rationale, oats from different processing stages and from different production systems, buckwheat, teff, pearl millet, and different genotypes of sorghum were analyzed for health relevant phenolic bioactive linked antioxidant and anti-hyperglycemic properties using in vitro assay models. Overall, high phenolic-linked antioxidant and anti-diabetic properties were observed in whole grain oats, rolled oat, buckwheat, teff, and select sorghum genotypes.

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Casañé, Riera Anna. "Tractament dietètic de la resistència a la insulina amb compostos bioactius i els seus efectes en el mitocondri." Doctoral thesis, Universitat de Lleida, 2014. http://hdl.handle.net/10803/285012.

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La síndrome metabòlica és una epidèmia creixent a tot el món i consisteix en un conjunt de factors de risc per a la malaltia cardiovascular i diabetis tipus 2. Es caracteritza per l’obesitat central, la hiperlipidèmia, la hipertensió i la resistència a la insulina; uns factors que estan vinculats amb els canvis de l’estil de vida de la població, causats pel consum de dietes hipercalòriques i d’un estil de vida sedentari. Les primeres línies de tractament per reduir la síndrome metabòlica són l’adequació de la ingesta calòrica i l’activitat física. No obstant, aquestes recomanacions sovint són difícils d’aplicar i la incorporació de diferents compostos bioactius a la dieta podria ser una alternativa útil per al tractament de la síndrome metabòlica. L’objectiu d’aquesta tesi ha estat avaluar l’efecte de la suplementació nutricional dels compostos bioactius omega-3 i fibra soluble i de la soja en paràmetres de resistència a la insulina, així com el seu potencial efecte en el metabolisme energètic i la memòria metabòlica, evidenciat per canvis en el mitocondri. S’ha utilitzat un model animal de ratolí al qual se li ha induït una resistència a la insulina amb una dieta hipercalòrica. Posteriorment s’ha tractat amb els compostos citats prèviament en contextos de dietes normocalòriques o hipercalòriques. Els resultats mostren que l’adequació energètica disminueix els paràmetres de risc estudiats relacionats amb la síndrome metabòlica. La suplementació amb els compostos bioactius en un context de dieta normocalòrica no ofereix un valor afegit en el tractament de la resistència a la insulina. No obstant, en un context de dieta hipercalòrica, l’addició dels compostos bioactius milloren els nivells de sensibilitat a la insulina de forma similar al tractament amb una dieta normocalòrica. Així mateix, l’addició dels compostos tant en un context de dieta normocalòrica com hipercalòrica, tendeixen a revertir els nivells en les proteïnes relacionades amb el mitocondri en comparació amb una dieta hipercalòrica. Tot i els canvis observats en relació amb la sensibilitat a la insulina i el mitocondri, la ingesta de soja i fibra soluble van incrementar alguns marcadors de dany oxidatiu proteic. Això suggereix que s’ha de tenir en compte els possibles efectes a llarg termini de la suplementació d’aquests compostos en situacions d’insulinorresistència. De forma general, es pot concloure que els efectes que produeixen les dietes hipercalòriques en situacions d’insulinorresistència en el mitocondri i possiblement en el metabolisme, poden ser revertits. Aquest fet suggereix que el mitocondri té una capacitat d’adaptació en relació a l’energia disponible.
El síndrome metabólico es una epidemia creciente en todo el mundo y consiste en un conjunto de factores de riesgo para la enfermedad cardiovascular y la diabetes tipo 2. Se caracteriza por la obesidad central, la hiperlipidemia, la hipertensión y la resistencia a la insulina; unos factores que están vinculados con los cambios de estilo de vida de la población, causadas por el consumo de dietas hipercalóricas y de un estilo de vida sedentario. Las primeras líneas de tratamiento para reducir el síndrome metabólico son la adecuación de la ingesta calórica y la actividad física. Sin embargo, estas recomendaciones a menudo son difíciles de aplicar y la incorporación de los diferentes compuestos bioactivos a la dieta podría ser una alternativa útil para el tratamiento del síndrome metabólico. El objetivo de esta tesis ha sido evaluar el efecto de la suplementación nutricional de los compuestos bioactivos omega-3 y fibra soluble y de la soja en parámetros de resistencia a la insulina, así como su potencial efecto en el metabolismo energético y la memoria metabólica, evidenciado por cambios en la mitocondria. Se ha utilizado un modelo animal de ratón al que se le ha inducido una resistencia a la insulina con una dieta hipercalórica. Posteriormente se ha tratado con los compuestos citados previamente en contextos de dietas normocalóricas o hipercalóricas. Los resultados muestran que la adecuación energética disminuye los parámetros de riesgo estudiados relacionados con el síndrome metabólico. La suplementación con los compuestos bioactivos en un contexto de dieta normocalórica no ofrecen un valor añadido en el tratamiento de la resistencia a la insulina. No obstante, en un contexto de dieta hipercalórica la adición de los compuestos bioactivos mejoran los niveles de sensibilidad a la insulina de forma similar al tratamiento con una dieta normocalórica. Así mismo, la adición de compuestos bioactivos tanto en un contexto de dieta normocalórica como hipercalórica, tienden a revertir los niveles en las proteínas relacionadas con la mitocondria en comparación con una dieta hipercalórica. A pesar de los cambios observados en relación con la sensibilidad a la insulina y la mitocondria, la ingesta de soja y fibra soluble incrementaron algunos marcadores de daño oxidativo proteico. Esto sugiere que se debe tomar en cuenta los posibles efectos a largo plazo de la suplementación de estos compuestos en situaciones de insulinorresistencia. De forma general, se puede concluir que los efectos que producen las dietas hipercalóricas en situaciones de insulinorresistencia en la mitocondria y posiblemente en el metabolismo, pueden ser revertidos. Este hecho sugiere que la mitocondria tiene una capacidad de adaptación en relación a la energía disponible.
Metabolic syndrome is a worldwide growing epidemic which is established by a combination of cardiovascular disease and type 2 diabetes risk factors. Metabolic syndrome is characterized by central obesity, hyperlipidemia, hypertension and insulin resistance; factors that are related with changes in the population lifestyles, caused by the consumption of hypercaloric diets and sedentary lifestyle. The first common treatment for reducing metabolic syndrome is the adjustment of calorie intake and physical activity. However, these recommendations are often difficult to apply and the addition of various bioactive compounds in the diet may be a useful alternative for the treatment of metabolic syndrome. The aim of this thesis was to evaluate the effects of the nutritional supplementation with bioactive compounds omega-3 and soluble fibre and soy in parameters of insulin resistance, as well as their potential effect on energy metabolism and metabolic memory, indicated by changes in mitochondria. An animal mouse models to which were induced insulin resistance by a hypercaloric diet was used. Afterwards, the animals were treated with the described bioactive compounds together with normocaloric and hypercaloric diets. The results showed that the adequation of energy intake decreases the values of the parameters related to the metabolic syndrome. The supplementation with the bioactive compounds in a context of normocaloric diet did not provide any added value for the treatment of insulin resistance. However, in a context of a hypercaloric diet, the addition of bioactive compounds revealed similar levels of insulin sensitivity like the treatment with a normocaloric diet. Moreover, the addition of bioactive compounds in a normocaloric or hypercaloric diet revert the changes in mitochondrial protein levels in comparison with a hypercaloric. Although the changes observed in relation to insulin sensitivity and the mitochondria, the intake of soy and soluble fibre increased the protein oxidative damage, suggesting possible long-term effects of the supplementation of these compounds in insulin resistance situations. It can be finally concluded that the observed effects in the mitochondria and possibly on the metabolism as a result of a hypercaloric diet in situations of insulin resistance can be reversed. Suggesting that the mitochondria has the capacity of adaptation in relation to energy availability.

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Hogan, Shelly Patricia. "Grape Extracts for Type 2 Diabetes Treatment Through Specific Inhibition of α-Glucosidase and Antioxidant Protection." Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/26725.

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Research was conducted to investigate the effect of phenolic compounds derived from inherently rich antioxidant grape extracts (GE) on α-glucosidase inhibitory activity in vitro and in vivo blood glucose control, oxidative stress, and inflammation associated with obesity-induced type 2 diabetes. Because intestinal α-glucosidase plays a key role in the digestion and absorption of complex carbohydrates, the inhibition of this enzyme is a metabolic target for managing diabetes by improving post-prandial blood glucose control. Initially, red Norton wine grape (Vitis aestivalis) and pomace extracts were evaluated and determined to have notable phenolic content and antioxidant properties. Next, grape skin (GSE) and pomace extract (GPE) were tested and both had in vitro yeast and mammalian α-glucosidase inhibitory activity. The GSE was 32-times more potent at inhibiting yeast α-glucosidase than acarbose, a commercial oral hypoglycemic agent. From HPLC and LC-MS analysis, three phenolics from the GSE (resveratrol, ellagic acid, and catechin) were identified as active inhibitory compounds. The acute administration of GPE (400 mg/kg bw) to mice reduced postprandial blood glucose level by 35% following an oral glucose tolerance test compared to the control. The daily supplementation (250 mg/kg bw) of GSE and GPE for 12-weeks to mice affected fasting blood glucose levels, oxidative stress, and inflammatory biomarkers associated with obesity and type 2 diabetes. At the end of the study, the GSE group gained significantly (P < 0.05) more weight (24.6 g) than the control, high fat, or GPE groups (11.2, 20.2, 19.6 g, respectively). Both GSE and GPE groups had lower fasting blood glucose levels (119.3 and 134.2 mg/dL, respectively) compared to the high fat group (144.6 mg/dL). The 12-week supplementation of GSE was associated with a higher plasma oxygen radical absorbance capacity (ORAC), lower liver lipid peroxidation as measure by TBARS, and lower levels of inflammation as measured by plasma C-reactive protein compared to the high fat group. In conclusion, our collective observations from these studies provide insight into the potential effects of antioxidant rich grape extracts on diabetes-related biomarkers through a dual mechanism of antioxidant protection and specific inhibition of intestinal α-glucosidases.
Ph. D.

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Marinho, Júlia Fernanda Urbano. "Desenvolvimento e avaliação de sorbets probióticos e simbióticos elaborados com polpa de Juçara (Euterpe edulis)." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/74/74132/tde-05052016-093018/.

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O objetivo deste trabalho foi desenvolver e avaliar diferentes formulações de sorbets probióticos e simbióticos a base de polpa de juçara (Euterpe edulis), de modo a combinar os efeitos benéficos à saúde dos compostos fenólicos deste fruto com os benefícios dos probióticos e prebióticos. Para isso, foram utilizados os microrganismos L. acidophilus e L. paracasei e a fibra polidextrose, além da elaboração de uma amostra controle sem tais elementos para efeito de comparação. Primeiramente, a polpa de juçara pasteurizada utilizada na produção dos sorbets foi avaliada de acordo com suas características físico-químicas e seus compostos bioativos, tendo apresentado resultados adequados para o emprego na matriz alimentícia em questão. Em seguida, os sorbets foram caracterizados através de diversos parâmetros. Assim, a análise centesimal mostrou sorbets com alto índice de carboidratos e baixo valor calórico, enquanto os teores de sólidos solúveis apresentaram-se coerentes em todas as formulações analisadas. Os valores de overrun e densidade aparente relevaram que a incorporação de ar dos sorbets não foi tão elevada quanto de um sorvete lácteo, embora as amostras adicionadas de polidextrose - capaz de mimetizar as propriedades de corpo e espessamento da gordura - tenham obtido resultados mais próximos aos gelados tradicionais. Foram ainda mensurados os efeitos do armazenamento dos produtos a -18 °C durante 120 dias, através de avaliações de pH, coloração instrumental, estabilidade dos compostos fenólicos e antocianinas e viabilidade dos probióticos. O pH das amostras manteve-se constante durante todo o experimento, com valores entre 4,4 e 4,8, enquanto os parâmetros de coloração caracterizaram as amostras como vermelhas e apontaram tendência à perda de luminosidade. Já os polifenóis e antocianinas apresentaram teores elevados, decorrentes da adição da polpa de juçara, sem a ocorrência de degradação destes compostos ao longo da estocagem das amostras sob congelamento. As populações de ambos os microrganismos adicionados apresentaram-se estáveis em cerca de 8 log UFC/ g durante todo o período de armazenamento, o que corresponde a um resultado bastante satisfatório e superior ao recomendado pela legislação brasileira. Por outro lado, a sobrevivência in vitro de tais probióticos quando submetidos aos fluidos gastrointestinais não apresentou resultados adequados para a garantia da funcionalidade destes produtos, com queda de viabilidade superior a 4 ciclos logarítmicos. A aceitabilidade sensorial e intenção de compra apresentaram resultados positivos para todas as formulações, com maior aceitação das amostras probióticas em relação ao controle e menor interesse pelas amostras com adição de prebiótico. Tal resultado demonstra que a incorporação destas bactérias em sorbets de juçara é capaz de melhorar a qualidade do produto, enquanto a adição de polidextrose pode diminuir sua aceitabilidade nas condições empregadas. Em síntese, os sorbets elaborados apresentaram resultados satisfatórios, demonstrando a viabilidade na produção deste tipo de alimento funcional adicionado de probióticos, prebiótico e rico em polifenóis, sendo a combinação de tais elementos capaz de potencializar os efeitos benéficos destes compostos e trazer vantagens fundamentais à microbiota intestinal e à saúde de quem os consome.
This work aimed to develop and evaluate different formulations of probiotic and synbiotic jussara (Euterpe edulis) sorbets in order to combine the beneficial effects of the fenolic compounds of this fruit with the benefits of probiotics and prebiotics. For this, the microorganisms L. acidophilus and L. paracasei and the fiber polydextrose were used and a control sample without such elements was developed for comparison. First, the pasteurized jussara pulp used in the production of sorbets was evaluated according to its physicochemical characteristics and its bioactive compounds and the results obtained showed that it was appropriate for employment in the food matrix. Then, sorbets were characterized by various parameters. The centesimal composition showed high levels of carbohydrates and low caloric value, while the soluble solids content were consistent in all analyzed formulations. The overrun and apparent density values showed that the air incorporated into sorbets was not as high as a dairy ice cream, although the samples with polydextrose - able to mimic the body and thickening properties of fat - have obtained results closer to traditional ice cream. The effects of storage of the products at -18 ° C for 120 days were also measured by pH assessments, instrumental color, stability of phenolic compounds and anthocyanins and viability of probiotics. The pH of the samples remained constant throughout the experiment, with values between 4.4 and 4.8, while the color parameters characterized the samples as red and showed a tendency to lose brightness. The levels of polyphenols and anthocyanins were elevated as a result of the addition of jussara pulp, without degradation of these compounds during storage of samples under freezing. The populations of both added microorganisms were stable at about 8 log CFU/ g throughout the storage period, which is a very satisfactory result and better than the recommended by Brazilian legislation. On the other hand, in vitro survival of the probiotics through simulated gastrointestinal fluids did not present appropriate results to guarantee the functionality of these products, with decrease of viability higher than 4 log cycles. The sensory acceptability and purchase intent showed positive results for all formulations, with greater acceptance of probiotic samples compared to control and less interest in the samples with prebiotic. This result demonstrates that the incorporation of these bacteria in jussara sorbets is able to improve the quality of the product while the addition of polydextrose may decrease the acceptability in conditions employed. In short, sorbets showed satisfactory results, demonstrating the viability of production of functional food with addition of probiotics, prebiotics and rich in polyphenols. The combination of these elements can enhance the beneficial effects and bring fundamental benefits to intestinal microbiota and to health of those who consume them.

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Koike, Amanda Cristina Ramos. "Compostos bioativos em flores comestíveis processadas por radiação." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-17082015-102839/.

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Flores comestíveis são cada vez mais utilizadas nas preparações culinárias, sendo também reconhecidas por seus potenciais efeitos benéficos na saúde humana, o que exige novas abordagens para melhorar a sua conservação e segurança. Estes produtos altamente perecíveis devem ser cultivados sem o uso de agrotóxicos. Tratamento de irradiação pode ser a resposta a estes problemas, garantindo a qualidade dos alimentos, aumentando seu prazo de validade e desinfestação. Tropaeolum majus L. (capuchinha) e Viola tricolor L. (amorperfeito) são flores amplamente utilizadas nas preparações culinárias, sendo também reconhecidas por suas propriedades antioxidantes e alto teor de compostos fenólicos. O objetivo deste estudo foi avaliar os efeitos dose-resposta da irradiação por gama e feixe de elétron (doses de 0, 0,5, 0,8 e 1 kGy) sobre a atividade antioxidante, compostos fenólicos, aspectos físicos e potencial antiproliferativo das flores comestíveis. O flavonoide Kaempferol-O-hexosídeo-Ohexosídeo foi o composto mais abundante em todas as amostras de flores de Tropaeolum majus, enquanto Pelargonidina-3-O-soporosídeo foi a principal antocianina. Em geral, as amostras irradiadas demonstraram maior atividade antioxidante. Nas amostras da Viola tricolor, os compostos fenólicos mais abundantes foram os flavonois, especialmente aqueles derivados da quercetina. Em geral, as amostras irradiadas com raios gama, independentemente da dose aplicada, apresentaram quantidades mais elevadas m compostos fenólicos, os quais também foram favorecidos pela dose de 1,0 kGy independente da fonte utilizada. A atividade antioxidante também foi maior entre as amostras irradiadas. As duas espécies de flores comestíveis não apresentaram as amostras não apresentaram potencial antiproliferativo e citotoxicidade. Assim, os tratamentos por irradiação aplicados, demonstraram ser uma tecnologia viável para preservar a qualidade de pétalas de flores comestíveis, considerando as exigências impostas para sua utilização.
Edible flowers are increasingly being used in culinary preparations, being also recognized for their potential valuable effects in human health, which require new approaches to improve their conservation and safety. These highly perishable products should be grown without using any pesticide. Irradiation treatment might be the answer to these problems, ensuring food quality, increasing shelf-life and disinfestation of foods. Irradiation treatment might be the answer to these problems, to ensure food quality, to increase shelf-life and disinfestation of foods. Tropaeolum majus L. (nasturtium) and Viola tricolor L. (johnny-jump-up) flowers are widely used in culinary preparations, being also acknowledged for their antioxidant properties and high content of phenolics. The purpose of this study was to evaluate the dose-dependent effects of gamma and electron beam irradiation (doses of 0, 0.5, 0.8 and 1 kGy) on the antioxidant activity, phenolic compounds, physical aspects and antiproliferative potential of edible flowers. Kaempferol-O-hexoside-O-hexoside was the most abundant compound in all samples of Tropaeolum majus flower while pelargonidin-3-O-sophoroside was the major anthocyanin. In general, irradiated samples gave higher antioxidant activity, probably due to their higher amounts of phenolic compounds, which were also favored by the 1.0 kGy dose, regardless of the source . The Viola tricolor samples displayed flavonols as the most abundant phenolic compounds, particularly those derived from quercetin. In general, gamma-irradiated samples, independently of the applied dose, showed higher amounts in phenolic compounds, which were also favored by the 1.0 kGy dose, regardless of the source. The antioxidant activity was also higher among irradiated samples. The two species of edible flowers have not provided the samples did not show potential antiproliferative and cytotoxicity. Accordingly, the applied irradiation treatments seemed to represent a feasible technology to preserve the quality of edible flower petals, considering the requirements imposed by their increasing uses.

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Moreira, Joana Catarina Henriques. "Agentes fitoquímicos da Persea Americana Mill. e seu potencial contributo na dermocosmética." Master's thesis, [s.n.], 2012. http://hdl.handle.net/10284/3568.

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Trabalho apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências Farmacêuticas
A sustentabilidade é um conceito complexo que se pode resumir na noção de desenvolvimento económico e social, sem provocar grandes danos ao ambiente e aos recursos naturais. Há, atualmente, inúmeros casos de aproveitamento e valorização de materiais que no passado eram rejeitados pelas indústrias agroalimentares e que devem servir de exemplo para todos os processos de produção alimentar, potenciando outras indústrias, como a indústria farmacêutica, nomeadamente na área da tecnologia de desenvolvimento de produtos dermocosméticos. Portugal apresenta condições edafo-climatéricas favoráveis para o cultivo da Persea americana Mill., concretamente na zona sul de Portugal continental e no arquipélago da Madeira. Este fruto, embora não seja reconhecido como um alimento inserido na dieta mediterrânica, apresenta propriedades benéficas para a saúde. A polpa do fruto abacate é uma fonte rica em energia, fornecendo elevado teor de ácido gordos insaturados, proteínas, vitaminas e minerais. No entanto, tal como noutros frutos, a pele e a semente não são comestíveis, podendo ser reutilizadas noutras indústrias devido à sua riqueza em compostos fitoquímicos. O presente trabalho teve como objetivo o estudo e caracterização química dos compostos extratáveis das diferentes partes do fruto abacate, nomeadamente, polpa, pele e semente, variedade “Hass”. Foi realizada a caracterização físico-química do fruto nos seus principais tecidos: polpa, pele e semente, através dos teores de humidade, acidez titulável, sólidos solúveis totais, proteínas totais, cinzas e gordura. Para a quantificação dos fitoquímicos com propriedades bioativas, foram estudados a vitamina C, vitamina E, carotenoides totais, fenólicos totais, flavonóides e compostos antociânicos. A eficácia da atividade antioxidante dos compostos bioativos depende das suas estruturas químicas e concentrações distribuídas amplamente pelo fruto. A partir dos extratos aquosos estudou-se a atividade antioxidante, por espectrofotometria usando o radical DPPH, de forma a atestar as propriedades apontadas a este fruto. A caracterização físico-química e antioxidante apresentaram um perfil qualitativo idêntico nos diferentes constituintes do fruto analisados, mas foram encontrados teores médios significativamente diferentes (p  0.05). Os resultados obtidos indicam, por meio de uma abordagem fitoquímica in vitro, a presença de diferentes metabolitos secundários com propriedades bioativas nos diferentes constituintes do fruto (polpa, pele e semente), visando o seu interesse na sua produção não só na vertente alimentar como potenciais recursos à indústria cosmética na elaboração de produtos naturais com atividade farmacológica e terapêutica. Sustainability is a complex concept that can be explained as the economic and social development without causing damages to the environment and the natural resources. Currently there are many cases of use and valorization of materials that were before rejected by the food industries and this should be an example for all food producing processes, enhancing other industries such as pharmaceuticals, particularly in the area of technology for development new cosmetic products. Portugal presents edaphoclimateric conditions favorable to the culture of Persea americana Mill., particularly in the south of Portugal and archipelago of Madeira. This fruit, although not recognized as a food included in the traditional Mediterranean diet, presents beneficial properties for health promotion. The fruit pulp is recognized as a rich source of energy, providing a high content of unsaturated fatty acids, proteins and minerals. However, like other fruit, skin and seeds of avocado fruits are not edible and can be reused due to its wealth of phytochemical compounds. The aim of the present work was the study and chemical characterization of extractable substances presented of the different parts of avocado fruit, in particular, pulp, skin and seeds of Hass variety. We performed the physicochemical characterization of the avocado fruit in its main tissues: pulp, skin and seed, through the moisture content, acidity, total soluble solids, protein content, ash and fat content. For quantification of some phytochemicals with bioactive properties it were studied the contents of vitamin C, vitamin E, carotenoids total phenolics, flavonoids and anthocyanin compounds. The effectiveness of antioxidant activity of bioactive components depends on their chemical structure and concentration widely distributed in fruit tissues. From aqueous extracts it was studied the antioxidant activity by spectrophotometry, using the DPPH radical, in order to testify the properties described for this fruit. The physico-chemical characterization and antioxidant profile showed a qualitatively identical in all different constituents analyzed in the fruit, but average levels were found significantly different (p  0.05). The results indicate, by means of a phytochemical in vitro approach, the presence of different secondary metabolites with bioactive properties in the various constituents of avocado fruit (pulp, skin and seed), to their interest in its production not only in the food industry, also, as a potential resources to the cosmetics industry in the development of natural products with pharmacological and therapeutic activities.

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Valente, Daniela Margarida Carvalho. "Pesquisa da atividade antioxidante em subprodutos alimentares: conceito de sustentabilidade." Master's thesis, [s.n.], 2015. http://hdl.handle.net/10284/5316.

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Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências Farmacêuticas
As indústrias agroalimentares produzem anualmente grandes quantidades de resíduos cuja valorização é ainda muito pequena. Atualmente sabe-se que apenas uma pequena parte é reaproveitada para a alimentação direta de gado ou para compostagem. A estratégia de implementar uma gestão de resíduos exequíveis, além de valorizar fortemente um subproduto, diminui consideravelmente a carga poluente resultante da atividade agroindustrial e potencia o sistema agrícola e económico de um país. A baixa ingestão de fibras, vitaminas e minerais é um hábito corrente na população mundial. Para aumentar o consumo desses nutrientes, várias alternativas têm sido propostas, dentre as quais a produção de novos géneros alimentícios enriquecidos com subprodutos alimentares, que possuam um valor nutricional superior ao alimento original, mas que sejam, ao mesmo tempo, acessíveis às classes economicamente menos favorecidas. Uma alternativa para esse problema é o recurso de novos ingredientes que possam aumentar o aporte nutricional comparativamente com os alimentos tradicionais já comercializados no mercado corrente. Com o intuito de valorizar os resíduos alimentares e provar que os mesmos apresentam propriedades biológicas idênticas às já descritas nas polpas das frutas cítricas, neste trabalho foi integrado um estudo baseado no desenvolvimento de um novo biscoito enriquecido com as cascas dos frutos cítricos estudados. Para isso, foram quantificados os teores de alguns compostos bioativos e a respetiva atividade antioxidante nas cascas e nas polpas de seis citrinos diferentes, de origem Portuguesa, nomeadamente a laranja (Citrus sinensis), o limão (Citrus limon), a clementina (Citrus clementina), a toranja (Citrus paradisi), a tangerina (Citrus reticulata) e a lima (Citrus aurantifolia). Determinou-se o teor de compostos fenólicos totais, flavonoides e carotenoides recorrendo a métodos espetrofotométricos previamente validados. A atividade antioxidante foi estudada através do método colorimétrico de inibição do radical livre 2,2-difenil-1-picril-hidrazilo (DPPH•). Este trabalho teve como objetivo adicional elaborar um novo biscoito enriquecido com cascas de citrinos pouco aproveitados ou normalmente subutilizados e caracterizá-los sensorialmente, recorrendo a um painel de 150 provadores não treinados, de forma monádica sequencial, usando uma escala de pontuação de Likert com 9 categorias, de extremamente agradável a extremamente desagradável. As amostras foram também avaliadas em relação à intenção de compra por parte dos consumidores, visando um futuro recurso de sustentabilidade e aumento de aporte nutricional.
The agro-food industries annually produce large quantities of waste which valorization is still very small. Currently it is known that only a small part is reused for cattle feed or used for composting. The strategy to implement a feasible waste management, and also enrich the food by-products, considerably reduces the pollutant load resulting from agro-industrial activity, enhances agricultural and economic system of a country. The low intake of fiber, vitamins and minerals is a common habit in the world population. To increase consumption of these nutrients, several alternatives have been proposed, among which the production of novel fortified foods, which may have higher nutritional value than the original food, but also at the same time, to be accessible to less economically favored classes. An alternative to this problem is to use new ingredients that can increase the nutritional intake compared to traditional foods already in the current market. In order to enhance food waste and also to prove that they have identical biological properties to those already described in the citrus fruit pulps, this work has been integrated into a study based on the development of a new biscuit enriched with the peels of six citrus fruits. For this reason, the content of some bioactive compounds and their antioxidant activity were analyzed in the peel and in the pulp of six different Portuguese citrus fruits, namely, orange (Citrus sinensis), lemon (Citrus limon), clementine (Citrus clementine), grapefruit (Citrus paradisi), tangerine (Citrus reticulata) and lime (Citrus aurantifolia). It was determined the content of total phenolics, flavonoids and carotenoids by using spectrophotometric methods, previously validated. The antioxidant activity was also studied using a colorimetric method, the free radical 2,2-diphenyl-1-picryl-hydrazyl (DPPH•) assay. In this work we elaborated a new enriched biscuit with citrus peel, by assessing them through a sensory analysis, using a panel of 150 untrained, following a sequential monadic manner, and using a Likert scoring scale with 9 categories: extremely pleasant to extremely unpleasant. The samples were also evaluated for purchase intent among consumers, aiming a future resource sustainability and increased nutrient intake.

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Monteiro, Gean Charles. "Fitoquímica e perfil sensorial de sucos de uvas e seus subprodutos /." Botucatu, 2020. http://hdl.handle.net/11449/192662.

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Orientador: Giuseppina Pace Pereira Lima
Resumo: O mercado de suco de uva está em crescimento, principalmente pelos benefícios do consumo a saúde. Várias soluções tecnológicas foram propostas para melhorar a cadeia produtiva, como a combinação de uvas e até mesmo o aproveitamento do resíduo do processo de produção, contribuindo na qualidade funcional, econômica e ambiental. No Brasil, uvas Vitis labrusca e híbridas representam a maioria daquelas destinadas aos sucos. A uva híbrida 'Niagara Rosada' que apresenta alta produtividade e aceitabilidade, com excedente de produção, pode ser uma opção para a produção de suco e utilização do resíduo para suplementação alimentar. Dessa forma, o perfil de compostos fenólicos e nitrogenados, bem como capacidade antioxidante e bioativa, coloração e sensorial foram realizadas com o objetivo de verificar a qualidade dos sucos de uva e seus resíduos produzidos a partir de combinações de 'Niagara Rosada'. Os sucos foram elaborados com 'Bordo', 'BRS Violeta', 'IAC 138-22 Máximo', separadamente e em blends com 'Niagara Rosada'. Os sucos foram produzidos por prensagem a quente, engarrafados (vidro âmbar) e pasteurizados. Um controle comercial (C) de 'Niagara Rosada' também foi analisado junto aos sucos. Os resíduos da produção do suco (bagaços) foram secos, moídos, embalados e armazenados para as análises. Treze misturas foram produzidas independentemente usando 100, 75, 50 e 25% de cada cultivar e em combinação com 'Niagara Rosada'. O perfil de polifenóis e compostos nitrogenados foram analisa... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The he grape juice market is growing, mainly due to the health benefits of consumption. Various technological solutions have been proposed to improve the production chain, such as the combination of grapes and even the use of the residue of the production process, contributing to functional, economic and environmental quality. In Brazil, Vitis labrusca and hybrid grapes represent the majority of those destined for juices. The hybrid grape 'Niagara Rosada', which presents high productivity and acceptability, with surplus production, can be an option for the production of juice and use of the residue for food supplementation. Thus, the profile of phenolic and nitrogen compounds, as well as antioxidant and bioactive capacity, coloring and sensory were carried out with the aim of verifying the quality of grape juices and their residues produced from 'Niagara Rosada' combinations. The juices were made with 'Bordo', 'BRS Violeta', 'IAC 138-22 Máximo', separately and in blends with 'Niagara Rosada'. The juices were produced by hot pressing, bottled (amber glass) and pasteurized. A commercial control (C) of 'Niagara Rosada' was also analyzed with the juices. The juice production residues (bagasse) were dried, ground, packaged and stored for analysis. Thirteen mixtures were produced independently using 100, 75, 50 and 25% of each cultivar and in combination with 'Niagara Rosada'. The profile of polyphenols and nitrogen compounds were analyzed via HPLC. Total phenolic compounds, total ... (Complete abstract click electronic access below)
Doutor

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Moura, Cristiane de. "Potencial antioxidante de extratos hidroalcoólicos de mirtilo, polpa de açaí e goji berry: efeito na estabilidade oxidativa e sensorial em queijo petit suisse." Universidade Tecnológica Federal do Paraná, 2016. http://repositorio.utfpr.edu.br/jspui/handle/1/1760.

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CAPES
O interesse do consumidor por alimentos saudáveis, ricos em compostos antioxidantes é um dos fatores importantes para a redução de riscos de doenças e vem incentivando os pesquisadores e a indústria a desenvolver produtos e ingredientes inovadores e funcionais. Com esse intuito, o objetivo do trabalho foi determinar as melhores condições de extração de compostos bioativos presentes nas amostras polpa de açaí, mirtilo e goji berry utilizando a metodologia de superfície de resposta (RSM); avaliar a atividade antioxidante e antimicrobiana; identificar e quantificar os compostos por cromatografia líquida de alta eficiência (CLAE); avaliar a estabilidade oxidativa e sensorial do queijo petit suisse contendo os extratos liofilizados das amostras estudadas. Delineamento fatorial 2³ foi usado para analisar o efeito do solvente (etanol e água), tempo (30 e 60 min) e temperatura (30 °C e 60 °C) na extração e na determinação de compostos fenólicos totais (TCF) e atividade antioxidante (AA). As variáveis, tempo e temperatura apresentaram efeito positivo na AA em seus maiores níveis, 60 min e 60 ºC, respectivamente. O solvente etanol 80 % se mostrou mais eficiente na extração de TCF com AA em todas as matrizes. A identificação de compostos fenólicos realizada por CLAE revelou a presença de catequina, epicatequina, rutina, miricetina, ácido caféico, ácido ferrúlico e ácido cumárico. A polpa de açaí apresentou maior atividade antioxidante in vitro quando extraída a 60 °C por 60 min, porém nenhum dos três extratos analisados nestas condições apresentaram atividade antibacteriana contra as bactérias Staphylococcus aureus e Salmonella bongori nas concentrações testadas (95,00 a 2,34 mg/mL). A oxidação lipídica dos petit suisse foi inibida pela adição dos extratos liofilizados, revelando hjhgjggredução na produção de substâncias reativas ao ácido tiobarbitúrico e proporcionando a estabilidade da cor dos produtos durante o tempo de estocagem. O queijo petit suisse contendo extrato liofilizado de goji berry obteve maior aceitação sensorial entre os julgadores (75,67 %). Com estes resultados a substituição de antioxidantes e ingredientes sintéticos por extratos liofilizados pode ser uma alternativa para a elaboração de alimentos mais saudáveis e nutritivos, ricos em compostos fenólicos.
The consumer interest in healthy foods with high amounts of antioxidants is one of the important factors for reducing the risk of disease and it has encouraged researchers and industry to develop innovative and functional products and ingredients. To that end, the objective of this research was to study the bioactive compounds present in the acai pulp, blueberry and goji berry samples, as well as the phenolic compounds form of extraction using the response surface methodology (RSM), antioxidant and antimicrobial activity of it, identification and quantification of compounds by high-performance liquid chromatography (HPLC) and, at the end, the development of petit suisse cheeses added with freeze-dried extracts of the samples. A 2³ factorial design was used to analyze the solvent effect (ethanol and water), time (30 and 60 min) and temperature (30 °C and 60 °C) on the extraction and determination of total phenolic compounds (TPC) and antioxidant activity (AA). The variables time and temperature had a positive effect on the antioxidant activity (AA) in their highest levels with 60 min and 60 °C respectively. The ethanol solvent 80 % is more efficient in TPC extraction with AA in all arrays. The identification of phenolic compounds performed by HPLC revealed the presence of catechin, epicatechin, rutin, myricetin, chlorogenic acid, coumaric acid and ferulic acid. Regarding the AA the acai pulp showed higher activity in vitro when extracted by 60 °C for 60 min, but none of the three extracts analyzed under these conditions showed antibacterial activity against Staphylococcus aureus and Salmonella bongori in the concentrations tested (95.00 to 2.34 mg/mL. For petit suisse cheeses added with phenolic extract of the samples, the sample containing goji berry achieved greater sensory acceptance among judges (75.67%), second only to the commercial sample used for comparison with 91.56 % of acceptance. In relation to the storage time, the oxidation was evaluated by the level of thiobarbituric acid reactive substances and color analysis. Both analysis were satisfactory, making the extracts addition an alternative to preserve the product properties and give it a high content of bioactive and nutritive compounds.

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Souza, Rosane Li?ge Alves de. "Estudo da funcionalidade de esp?cies comest?veis do semi?rido nordestino e estrat?gias para sua utiliza??o como ingredientes para fins aliment?cios." Universidade Federal do Rio Grande do Norte, 2014. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15935.

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The Brazilian caatinga is characterized by low annual rainfall and arid soils. Several cactaceae, either native or adapted species, grow in this semi-arid region, including the prickly pear (Opuntia f?cus indica) and facheiro ((Philosocereus pachycladus Ritter) which produce underexploited edible fruits. In addition to these species, the algaroba is a leguminous with little studied technological applications and bioactive potential so far. Therefore, this research aims to investigate the physicochemical, bioactive and functional attributes of the prickly pear and facheiro fruit pulps and the algaroba flour. Specifically, this study approaches the physicochemical characterization, total phenolic compounds (TPC) and the betalain identification and quantification by HPLC-DAD-ESI-MS. It is also investigated the DPPH antioxidant capacity and the antienzymatic activities against alpha-amylase and alphaglucosidase of water and ethanolic extracts of these food material. In order to address their potential to be used as food ingredients, juice blends prepared with mixtures of caj? and prickly pear, biofilms with facheiro and cereal bars with algaroba flour were elaborated and analyzed. The prickly pear fruits presented low acidity and high sugar content when compared to facheiro. The Philosocereus pachycladus Ritter fruits had higher protein and ash content, but the algaroba flour was the species with higher protein and sugar content among all. The algaroba flour also presented outstanding food fiber content, which reveals its potentiality to be used as a natural intestinal regulator. The TPC of water and ethanol extracts ranged from 3.87 to 16.21 mg GAE/100g for algaroba flour, 79.24 to 110.20 GAE/ 100g for prickly pear and 412.23 to 539.14 mg GAE/100g for facheiro. The 70% (w/v) ethanol extract reached the highest DPPH antioxidant activity, which was linearly correlated to its high TPC content. In regard to the enzymatic inhibitory activities, the best performance was observed for the prickly pear extracts which presented a moderate inhibition for both investigated enzymes, but interestingly, no alpha-glucosidase inhibition was observed for facheiro extracts. This work shows, for the first time in the literature, the functional attributes of facheiro fruits, as well as the presence of betacianins and isobetanin in the pulp of this exotic fruit. When it comes to the food products developed here, the sensory attributes that better described the juice blend caj?-prickly pear were sweetness, acidity, color yellow-orange, body, turbidity and caj? flavor. The discriminative test applied for cereal bars produced with and without algaroba revealed that the texture was the only sensory attribute that differed (p<0.05) between these two samples. It was also observed that the addition of facheiro extracts did not influence the visual characteristics of the biofilms. Overall, this work unveils the physicochemical and bioactive attributes of these commercial and technologically underexploited species widely found in the Brazilian caatinga and presents alternatives for their rational use
O semi?rido brasileiro configura-se por condi??es clim?ticas e de solo desfavor?veis e vegeta??o resistente a longos per?odos de estiagem. As esp?cies de cact?ceas nativas ou adaptadas ? regi?o, como o figo da ?ndia (Opuntia f?cus indica) e facheiro (Philosocereus pachycladus Ritter), t?m frutos comest?veis pouco conhecidas. Al?m destas esp?cies, a leguminosa algaroba ? uma mat?ria-prima com caracter?sticas ainda pouco investigadas do ponto de vista tecnol?gico e teor de subst?ncias bioativas. Desta forma, este trabalho objetivou realizar a caracteriza??o f?sico-qu?mica, bioativa e funcional da polpa das cact?ceas figo da ?ndia e facheiro e da farinha de algaroba. O estudo incluiu a determina??o do teor de compostos fen?licos, identifica??o e quantifica??o das betala?nas por HPLC-DADESI- MS, al?m da investiga??o da atividade antioxidante e inibi??o das enzimas alfa-amilase e alfa-glicosidase, utilizando extratos aquosos e etan?licos obtidos a partir das esp?cies avaliadas. Como estrat?gias de aproveitamento, elaborou-se suco misto do figo da ?ndia, biofilmes a partir do facheiro e barra de cereal a partir da farinha de algaroba. A caracteriza??o do figo da ?ndia revelou baixa acidez e elevada do?ura, quando comparada ao facheiro. O fruto do Philosocereus pachycladus Ritter, por sua vez, apresentou maior conte?do prot?ico e de cinzas. No entanto, a maior fra??o proteica e a??cares est? contida na farinha de algaroba. O conte?do de fibra alimentar total (FAT) revelou a potencialidade da farinha de Prosopis juliflora para atuar como reguladora da fun??o intestinal. O teor de fen?lico total para extratos aquosos e etan?licos variaram de 3,87 a 16,21 mg GAE/100g para a farinha de algaroba, 79,24 a 110,20 mg GAE/100g para o figo da ?ndia e facheiro 412,23 a 539,14 mg GAE/100g. O extrato etan?lico a 70% do figo da ?ndia apresentou elevada atividade antioxidante, por?m o meior percentual fen?lico foi observado no facheiro. Em rela??o ? inibi??o enzim?tica, o melhor desempenho foi observado em extratos do figo da ?ndia, os quais exibiram inibi??o moderada para as duas enzimas estudadas, enquanto que n?o foi identificada inibi??o glicol?tica para o extrato aquoso de facheiro. O presente trabalho mostra, pela primeira vez na literatura, resultados in?ditos sobre a funcionalidade do facheiro, que incluem a presen?a das betala?nas betacianina e isobetanina na polpa desse fruto. No que diz respeito aos produtos desenvolvidos, as caracter?sticas sensoriais que melhor descreveram o suco misto de figo da ?ndia e caj? foram do?ura, acidez, cor amarela-alaranjada, corpo, turbidez e aroma de caj?. A an?lise discriminativa da barrinha de cereal elaborada com e sem farinha de algaroba mostrou que apenas o atributo textura foi diferente estatisticamente (p < 0,05) para as formula??es testadas. Os resultados tamb?m indicam que a adi??o do extrato do facheiro n?o modificou visualmente as caracter?sticas dos biofilmes. De maneira geral, o presente estudo revela as caracter?sticas f?sico-qu?micas e bioativas desses vegetais abundantemente encontrados na caatinga brasileira, mas ainda pouco explorados sob pontos de vista tecnol?gico e comercial, bem como sugere alternativas de aproveitamento para tais esp?cies

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BEZERRA, Júlia Medeiros. "Quantificação de compostos bioativos e capacidade antioxidante em cultivares de feijão-caupi." Universidade Federal de Campina Grande, 2015. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/845.

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O feijão é uma leguminosa largamente consumida no mundo, estando-lhe associadas diferentes propriedades nutricionais. Com o presente estudo visou-se avaliar a influencia do cozimento na composição centesimal, compostos bioativos e capacidade antioxidante de cultivares de feijão-caupi. Foram analisadas oito cultivares: Costela de Vaca, BRS Marataoã, BRS Itaim, BR 17-Gurguéia, BRS Novaera, Paulistinha, Setentão e Patativa. Os grãos de cada cultivar foram submetidos a dois procedimentos diferentes para realização das análises: cru (pó homogêneo) e cozido (com maceração) sob pressão. Analisou- se a composição química das amostras, que incluiu a composição centesimal, com determinação da umidade, cinzas, lipídios, proteínas, carboidratos e valor energético, os parâmetros físico-químicos como pH, acidez, e açúcares, além das análises dos compostos bioativos, como os compostos fenólicos, ácido ascórbico, flavonoides, antocianinas e a capacidade antioxidante. Todas as análises foram realizadas em quadruplicata nas cultivares cruas, cozidas e do caldo de cocção, sendo os resultados expressos como média ± desvio-padrão. Realizou-se a análise de variância e as médias foram comparadas pelo teste de Tukey (p<0,05). Em relação a composição centesimal, o conteúdo de umidade ficou na faixa de 7-11% nas cultivares cruas e aumentou nas cozidas (60-70%). O conteúdo de proteínas diminuiu de forma significativa (p<0,05) para todas as cultivares cozidas, assim como também o teor de cinzas, carboidratos e valor energético nas oito cultivares avaliadas. Para o conteúdo de açúcares totais e redutores, as cultivares cruas apresentaram teores de 11-13 mg /100 g e de 2-3 mg/100 g respectivamente, após o cozimento, foi observado uma redução destes teores.Para os compostos bioativos, a cultivar BRS Marataoã apresentou os maiores conteúdos de compostos fenólicos totais antes do cozimento (112,15 mg/100 g), após o cozimento houve uma redução destes compostos em todas as cultivares, com teores de 12-15 mg/100g, e o caldo apresentou maiores conteúdos, variando de 11-52 mg/100 g. Foram constatadas pequenas concentrações de antocianinas nas cultivares cruas, cozidas e no caldo de cocção, com destaque para a cultivar BRS Novaera (1,24 mg/100g-1) em sua forma cozida. Para a capacidade antioxidante, observaram-se comportamentos diferenciados para cada cultivar no método avaliado. Antes do cozimento, a cultivar BRS Marataoã apresentou maior capacidade antioxidante (57,69 g feijão. g DPPH-1). Após ocozimento, o caldo de cocção apresentou melhores resultados em relação aos grãos cozidos para seis das oito cultivares avaliadas, com destaque para a cultivar Costela de Vaca. Foi constatada forte correlação entre a capacidade antioxidante e o teor de fenólicos, flavonoides totais e ácido ascórbico. Concluiu-se que após o processamento, as cultivares mantiveram características nutritivas e funcionais relevantes, recomendando-se o consumo do feijão-caupi com o caldo de cocção para retenção de compostos com propriedades antioxidantes.
The beans is a legume that is widely consumed in the world, being it associated different nutritional properties. With the present study aimed to evaluate the influence of cooking on the chemical composition, bioactive compounds and antioxidant capacity of cowpea cultivars. Eight cultivars were analyzed: Costa de Vaca, Marataoã BRS, BRS Itaim, BR-17 Gurguéia, BRS Novaera, Paulistinha, Setentão and Patativa. The grain of each cultivar were submitted to two different procedures for carrying out the analyzes: raw (homogeneous powder) and cooked (maceration) under pressure. Was analyzed the chemical composition of samples that included the chemical composition, with determination of moisture, ash, lipids, proteins, carbohydrates and energy, the physical and chemical parameters such as pH, acidity and sugar, in addition to analyzes of bioactive compounds such as phenolic compounds, ascorbic acid, flavonoids, anthocyanins and antioxidant capacity. All analyzes were carried out in quadruplicate in raw varieties, cooked and cooking broth and the results expressed as mean ± standard deviation. We conducted the analysis of variance and the means were compared by Tukey test (p <0.05). With respect to chemical composition, moisture content was in the 7-11% range in the raw samples and increased the cooked (60-70%). The protein content significantly decreased (p <0.05) for all baked varieties, as well as ash, carbohydrates and energy value in the eight cultivars. For the content of total and reducing sugars, the raw samples showed levels of 11-13 mg / 100 g and 2-3 mg / 100 g respectively, after cooking, it was observed a reduction in these levels. For bioactive compounds, BRS Marataoã had the highest total phenolic content before cooking (112.15 mg / 100 g), after cooking there was a reduction of these compounds in all cultivars with levels of 12-15 mg / 100g, and the broth showed higher contents ranging from 11-52 mg / 100 g. small concentrations of anthocyanins were found in raw varieties, cooked in broth and cooking, especially BRS Novaera (1.24 mg / 100g-1) in its cooked form. For the antioxidant capacity, there were different behaviors for each cultivar in the assessed method. Before cooking, BRS Marataoã showed higher antioxidant capacity (57.69 g beans. DPPH-1g). After cooking, the cooking broth showed better results compared to baked beans for six of the eight cultivars, especially to cultivate Costa cow. strong correlation between antioxidant capacity and phenolic content, total flavonoids and ascorbic acid was found. It was concluded that after processing, cultivars maintained relevant nutritional and functional characteristics, it is recommended to cowpea consumption with broth cooking for retaining compounds with antioxidant properties.

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Amancio, Rodrigo Dantas. "Consumo de carotenoides no Brasil: a contribuição da alimentação fora do domicílio." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/11/11141/tde-19122012-091136/.

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Carotenoides são considerados substâncias bioativas e seu consumo tem sido associado à prevenção de doenças crônicas não transmissíveis. Os carotenoides com atividade pró-vitamínica atuam no combate à hipovitaminose A. O objetivo desta dissertação foi descrever a ingestão de carotenoides, destacando a contribuição do consumo fora do domicílio, de acordo com fatores socioeconômicos, demográficos e estado nutricional, além de identificar as principais fontes alimentares presentes na dieta da população brasileira. Utilizou-se como base de dados as informações integrantes do bloco de consumo alimentar pessoal, da Pesquisa de Orçamentos Familiares (POF 2008-2009), realizada pelo Instituto Brasileiro de Geografia e Estatística (IBGE), que envolveu 34.003 indivíduos com idade de 10 anos ou mais. Um banco de dados foi construído para viabilizar o cálculo das quantidades (médias) de carotenoides presentes na dieta dos participantes da amostra. Foram utilizadas principalmente informações contidas na base Nutrient Database for Standard Reference Release 23 - United States Department of Agriculture (USDA) e a Tabela Brasileira de Composição de Carotenoides em Alimentos. Foram elaboradas análises estatísticas descritivas envolvendo o cálculo de ingestão de carotenoides no domicílio e fora dele e as variáveis selecionadas. O consumo médio per capita foi de 4.117,0 µg/dia para carotenoides totais e 2.337,9 µg/dia para os pró-vitamínicos A. As maiores médias de ingestão de carotenoides (totais; pró-vitamínicos) foram identificadas entre os seguintes grupos: mulheres (4.245,8 µg/dia; 2.458,9 µg/dia), moradores do meio urbano (4.143,2 µg/dia; 2.364,20 µg/dia), habitantes da Região Sul (4.987,6 µg/dia; 2.948,9 µg/dia), idosos (4.694,3 µg/dia; 2.853,8 µg/dia), indivíduos com os maiores rendimentos (5.596,7 µg/dia; 3.236,6 µg/dia), com curso de pós-graduação completo (7.009,7 µg/dia; 4.143,5 µg/dia), de cor amarela (5.692,7 µg/dia; 3.436,9 µg/dia) e aqueles classificados com os maiores Índice de Massa Corporal - IMC (4.445,1 µg/dia; 2.535,0 µg/dia). Constatou-se que a contribuição fora do domicílio representou até ¼ da ingestão total de carotenoides. Observou-se que os indivíduos do sexo feminino, idade acima de 60 anos e obesos, embora ingerissem maiores quantidades destas substâncias, integraram os grupamentos que (em relação ao total) apresentaram menor participação na ingestão fora do domicílio. O crescimento da renda e da escolaridade foi fundamental para proporcionar níveis mais elevados de consumo. As principais fontes de carotenoides na dieta da população brasileira foram: salada, suco, alface, tomate, mamão, melancia, abóbora, batata-doce, cenoura, milho verde e ovo de galinha. Fora do domicílio prevaleceu a ingestão dos três primeiros alimentos/preparações. Os níveis de ingestão revelaram-se expressivamente inferiores aos preconizados como seguros. Medidas de incentivo ao consumo de frutas, verduras, legumes e seus derivados (fontes de carotenoides), sobretudo entre os jovens, são necessárias e prioritárias, especialmente com vistas à prevenção de doenças crônicas não transmissíveis e no combate à hipovitaminose A.
Carotenoids are considered bioactive substances and its consumption has been associated to prevention of chronic non communicable diseases. The carotenoids with pro-vitamin activity act against hypovitaminosis A. The aim of this dissertation was to report the carotenoids intake, highlighting the contribution of outof- home food consumption, accordingly with socioeconomic and demographical factors, nutritional status, also to identify the main food sources in the diet of Brazilian population. A secondary data from the 2008-2009 Household Budget Survey - POF - was used, published by the Brazilian Institute of Geography and Statistics (IBGE). The sample consisted of 34,003 study subjects (13,569 households), with at least 10 years-old. A database was built to allow the calculation of quantities (average) of carotenoids in the diet of study participants. Information was used primarily by the Nutrient Database for Standard Reference Release 23 - United States Department of Agriculture (USDA) and the Brazilian Table of Carotenoids Composition in Food. Descriptive statistical analysis was performed for calculation of carotenoid intake at home and out-of-home consumption. The average daily consumption per capita was 4,117.0 µg/day for total carotenoids and 2,337.9 µg/day for provitamin A carotenoids. The highest average intake of carotenoids (total; provitaminic) was found between the following groups: women (4,245.8 µg/day; 2,458.9 µg/day), urban dwellers (4,143.2 µg/day; 2,364.20 µg/day), South region population (4,987.6 µg/day; 2,948.9 µg/day), elderly people (4,694.3 µg/day; 2,853.8 µg/day), high-income individuals (5,596.7 µg/day; 3,236.6 µg/day), with full graduate degree (7,009.7 µg/day; 4,143.5 µg/day), yellow skinned person (5,692.7 µg/day; 3,436.9 µg/day) and those classified with highest Body Mass Index (BMI) (4,445.1 µg/day; 2,535.0 µg/day). The out-ofhome contribution found in this present study represented up to ¼ of the total intake of carotenoids. It was observed that individuals over 60 years, female and obese people, although ingested larger amount of these substances, belonged to the groups (in relation with total) which showed less interest in out-of-home eating. The increase in income and education was essential to provide higher levels of consumption. The main dietary carotenoids sources of Brazilian population were: salad, juice, lettuce, tomato, papaya, watermelon, pumpkin, sweet potato, carrot, corn and chicken egg. The consumption of first three food/preparation prevailed outside the home. The intake levels showed expressively lower than those recommended as safe. Policies to promote the consumption of fruits, vegetables and derived products (carotenoids sources) are necessary and priority, particularly among young people, especially aiming to prevent the risk of chronic diseases and combating hypovitaminosis A.

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Salinas-Roca, Blanca. "Preserving natural attributes of mango products by non-thermal technologies." Doctoral thesis, Universitat de Lleida, 2017. http://hdl.handle.net/10803/405840.

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Els consumidors demanden nous productes a base de fruites -com els a punt per menjar-, segurs, saludables i amb propietats similars als naturals. L’objecte d’estudi d’aquesta tesi doctoral fou avaluar l’impacte de tractaments no tèrmics en propietats de qualitat de diversos productes de mango: tallat, suc i puré. Per una banda, l’efecte de diferents recobriments a base de polisacàrids, alginat (AL), quitosan (CH), pectina (PE) i carboximetilcel·lulosa (CMC), es va avaluar en la conservació de la qualitat del mango tallat. També, l’efecte dels polsos de llum (PL) combinats amb el recobriment AL i la immersió en àcid màlic (MA) va permetre allargar la conservació dels atributs naturals durant 14 dies. D’altra banda, es va estudiar la influència dels polsos elèctrics d’alta intensitat de camp HIPEF a 35 kV/cm, 4 μs- pols bipolar, 200 Hz i 50- 2000 μs en la reducció de població de Listeria innòcua, l’activitat enzimàtica, les propietats sensorials així com el contingut de bioactius. En aquest sentit el contingut de fenols en el suc tractat per HIPEF (1800 μs) va millorar després de 59 dies. Finalment, es va estudiar l’impacte del tractament d’alta pressió hidrostàtica (HHP) (400, 450, 500 MPa durant 0 a 16 min a 34 o 59°C) en les propietats fisicoquímiques i enzimàtiques, com també en el contingut de compostos bioactius del puré de mango. Aquesta investigació mostra la viabilitat de la conservació dels derivats de fruita mitjançant tecnologies no tèrmiques.
Consumers are currently demanding safe, healthy and novel fruit products, such as ready-to-eat, with natural attributes. Therefore, the aim of the present doctoral thesis was to assess the impact of non-thermal treatments on quality properties of various mango products: fresh-cut, juice and puree. On one hand, the effect of different polysaccharide-based coatings, alginate (AL), chitosan (CH), pectin (PE) and carboxymethylcellulose (CMC) was evaluated on the quality preservation of fresh-cut mango. Also in fresh-cut mango, the effect of pulsed light (PL) combined with AL coating and malic acid (MA) dipping extended preservation of natural attributes throughout 14 days. On the other hand, the influence of high intensity pulsed electric fields (HIPEF) at 35 kV/cm, 4 μs- bipolar pulses, 200 Hz and 50-2000 μs in mango juice was studied in the reduction of Listeria innocua population, enzymatic activities, physicochemical and sensorial attributes as well as the content of bioactive compounds. In this sense, phenolic content in mango juice treated with HIPEF (1800 μs) was improved after 59 days. Finally, the impact of high hydrostatic pressure (HHP) treatments (400, 450, 500 MPa for 0 to 16 min at 34 or 59°C) on physicochemical, enzymatic properties and bioactive compounds of mango puree was observed. This research reveals the feasibility of preserving fruit products by non-thermal technologies.
Los consumidores piden nuevos productos a base de frutas, como los listos para el consumo, seguros, saludables y con propiedades similares a los naturales. Por lo tanto, el objeto de estudio de la presente tesis doctoral fue evaluar el impacto de tratamientos no térmicos en la calidad de diversos productos de mango: cortado, zumo y puré. Por un lado, el efecto de diferentes recubrimientos a base de polisacáridos, alginato (AL), quitosano (CH), pectina (PE) y carboximetilcelulosa (CMC) se evaluó en la conservación de la calidad del mango cortado. También, el efecto de los pulsos de luz (PL) combinado con el recubrimiento AL y la inmersión en ácido málico (MA) permitió alargar la conservación de los atributos naturales durante 14 días. Por otro lado, se estudió en el zumo de mango la influencia de los pulsos eléctricos de alta intensidad de campo (HIPEF) a 35 kV/cm, 4 μs- pulso bipolar, 200 Hz y 50- 2000 μs en la reducción de población de Listeria innocua, la actividad enzimática, las propiedades sensoriales así como el contenido de bioactivos. En este sentido el contenido de fenoles en el zumo de mango tratado por HIPEF (1800 μs) mejoró después de 59 días. Finalmente, el impacto del tratamiento por alta presión hidrostática (HHP) (400, 450, 500 MPa de 0 a 16 min a 34 o 59°C) se observó en las propiedades fisicoquímicas y enzimáticas y en el contenido de compuestos bioactivos en el puré de mango. La presente investigación muestra la viabilidad de la conservación de derivados de frutas mediante tecnologías no térmicas.

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Cury, Renata Del Bel. "Compostos bioativos presentes em produtos infantis e sua ação anti radical livre." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256516.

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Orientador: Adriana Zerlotti Mercadante
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
Made available in DSpace on 2018-08-10T19:18:08Z (GMT). No. of bitstreams: 1 Cury_RenataDelBel_M.pdf: 406098 bytes, checksum: 03090f5878c4c5284bd0fd52c8de4c80 (MD5) Previous issue date: 2008
Resumo: Cada vez mais se associa o consumo de frutas e vegetais à prevenção do câncer, doenças cardiovasculares, osteoporose e diabetes por serem excelentes fontes de compostos fitoquímicos com ação antioxidante que evitam o estresse oxidativo e seus efeitos. Os carotenóides, compostos fenólicos (inclui flavonóides e antocianinas) e ácido ascórbico são os compostos antioxidantes mais abundantes em frutas e vegetais. Entretanto, na primeira infância o consumo de frutas e vegetais in natura tem sido substituído por alimentos industrializados na forma de alimentos infantis (¿baby-food¿). Como o teor destes compostos antioxidantes presentes em produtos infantis a base de frutas e vegetais comercializados no Brasil ainda não foram determinados, o escopo deste trabalho foi analisar os teores de carotenóides, fenóis, flavonóides e ácido ascórbico e com o uso dos métodos ABTS e DPPH foi medido a atividade anti radical livre destes produtos. Além disso, foi avaliado o efeito do aquecimento em microondas sobre os teores dos compostos antioxidantes. Foram analisadas papinhas de ameixa, goiaba, maçã, pêra, banana e sopinhas de cenoura e mandioquinha adquiridas no comercio da cidade de Campinas, estado de São Paulo. A maior concentração de carotenóides totais foi observada na papinha de cenoura (6,4 mg/100g). A papinha de ameixa foi a que mostrou o maior teor de fenóis totais (49,3 mg/100g) e de flavonóides totais (38,5 mg/100g) sendo que também apresentou a melhor desativação do radical ABTS. Devido à sua adição nos produtos de frutas, foram encontrados altos valores de ácido ascórbico de 262 mg/100g para goiaba, 350 mg/100g para pêra, 475 mg/100g para banana, 150 mg/100 para ameixa e 122 mg/100g para maçã. Não foi detectado flavonóides totais nas sopinhas de legumes e nem antocianinas totais nas papinhas de goiaba e ameixa. Não houve perda significativa de carotenóides totais, fenóis totais e ácido ascórbico após aquecimento em microndas das sopinhas de legumes. Houve melhor correlação entre o teor de fenóis totais (r=0,93) e a atividade anti radical livre ABTS do que com o teor de flavonóides totais (r=0,86). Houve ainda correlação negativa em relação aos teores de carotenóides totais (r= -0,0854) e ácido ascórbico (r= -0,7049) e a atividade anti radical livre (ABTS). Foi observada baixa correlação (r=0,78) entre os métodos anti radical livre ABTS e DPPH
Abstract: The association between a diet rich in fruits and vegetables and decreased risk of cancer, cardiovascular disease, osteoporosis and diabets is supported because these foods are excelent sources of bioactive compounds with antioxidant activity that can act or prevent the effects of oxidative stress. Carotenoids, phenolic compounds (including flavonoids and anthocyanins) and ascorbic acid, are the most abundant antioxidant compounds in fruits and vegetables. However, the consumption of fruits and vegetables in the first childhood has been substituted by commercial baby foods. Since the levels of these antioxidant compounds found in baby foods commercialized in Brazil were not previously determined, the aim of this study was to quantify the contents of carotenoids, phenolic compounds, flavonoids and ascorbic acid, as well as to evaluate the antioxidant activity by two methods (ABTS and DPPH·) on some Brazilian baby foods. In addition, the effect of microwave heating on these antioxidant compounds was determined. The following baby products were analyzed: guava, dried plum, apple, pear and banana, ) and the vegetables ones (carrot and ¿mandioquinha¿). The highest concentration of total carotenoid was found in carrot baby food (6.4 mg/100g). Dried plum product had the highest contents of total phenols (49.3 mg GAE/100g) and total flavonoids (38,5 mg CE/100g) and also was the best free radical scavenger product assessed by the ABTS method. Since ascorbic acid is added to the based fruits baby foods, its contents were higher in all of them, such as 262 mg/100g in guava, 350 mg/100g in pear, 475 mg/100g in banana, 150 mg/100 in plum and 122 mg/100g in apple. .The vegetable baby s foods did not present flavonoids and anthocyanins were not detected in guava and dried plum baby foods. The losses of total carotenoids, total phenols and ascorbic acid were not statistically significant after microwave heating of vegetable baby foods. The highest correlation was observed between the total phenolic contents (r=0.93) ABTS·+ scavenger, followed by total flavonoids (r=0,86). However, negative correlations between the ABTS method and total carotenoids (r= -0,0854) and total phenols (r= -0,7049) were obtained. There was weak correlation (r=0.73) between the two free radical scavenger methods DPPH and ABTS
Mestrado
Mestre em Ciência de Alimentos

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Li, Shangxiao. "Bioactive compounds from New Zealand marine organisms." Thesis, University of Canterbury. Chemistry, 1988. http://hdl.handle.net/10092/7314.

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Primary screening of recent collections from the sea around New Zealand revealed a wide range of bioactivities, including antitumour, antiviral and anti-HIV activities. Seven marine organisms, including sponges and an ascidian, were examined to identify the active compounds responsible for these three type of biological activities. A chemical screening protocol was established for the dereplication and prioritization of antiviral natural product extracts, which was also applied to extracts with other bioactivities. A recent modification included HPLC analysis of the eluates from solid phase extraction cartridges, coupling the UV profiles of the corresponding peaks in the HPLC traces with MarinLit database. Extracts from two marine sponges which contained known cytotoxic compounds, pateamine and calyculins respectively, were used to test the efficiency of the modified protocol. These two types of active compounds were quickly identified by searching the UV data field in MarinLit. HIV -inhibitory activity was recognised in both aqueous and organic extracts from a sponge Chondropsis kirkii. The aqueous extract was processed on a Sephadex-25 column. The positive results of a toluidine blue test on the resultant fractions suggested that sulphated polysaccharides may be responsible for the potent anti-HIV activity. The HIV -inhibitory components in the organic extract turned out to be a mixture of sterols. However, an increase of the cytotoxicity with increasing sample purity was also observed. Examination of a sponge Callyspongia irregularis resulted in the isolation of a known compound, mycalamide A, which is a potent antiviral agent. Purification of the trace amount of compound obtained was mainly achieved by high speed countercurrent chromatography (HSCCC). Examination of another Callyspongia species has led to the discovery of a potently cytotoxic fraction (IC₅₀ 11 ng/mL). A New Zealand deep water sponge, Lamellomorpha strongylata, has turned out to be a rich source of bioactive compounds. Bioassay-guided analysis led to the separation of five new cytotoxic theonellapeptolides IIIa, IIIb, IIIc, IIId and IIIe (molecular-weight 1376-1453). These tridecapeptides were characterised by amino acid analysis using GC-MS, sequencing the ring-opened peptides with FABMS-MS, and ID (¹H, ¹³C, DEPT and decoupling experiment) and 2D (COSY, TOCSY, HMQC-TOCSY, HMBC, HSMQC and ROESY) NMR, IR analysis and chemical reaction. Of these, the MS-MS technique played a very important role in sequencing. These compounds exhibited weak cytotoxicity. However, the other member of the theonellapeptolide family showed ion-transport properties. The absolute stereochemistry of IIIe was determined by X-ray crystal structure analysis in conjunction with a chiral HPLC method. The solution conformations of IIIb and IIIe were established mainly by correlations in the ROESY spectra. Six optically pure N-methyl amino acids were synthesised for a study of the stereochemistry of the component amino acids. The absolute stereochemistry of IIIa, IIIb, IIIe and IIId were determined by chiral LC-MS analysis. In addition, three minor components were isolated from the same sponge. ¹H NMR spectra showed that they all contained peptide components.

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Soldati, Roberto <1986&gt. "Synthesis of new bioactive β-lactam compounds." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6974/.

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New biologically active β-lactams were designed and synthesized, developing novel antibiotics and enzymatic inhibitors directed toward specific targets. Within a work directed to the synthesis of mimetics for RGD (Arg-Gly-Asp) sequence able to interact with αvβ3 and α5β1-type integrins, new activators were developed and their Structure-Activity Relationships (SAR) analysis deepened, enhancing their activity range towards the α4β1 isoform. Moreover, to synthesize novel compounds active both against bacterial infections and pulmonary conditions of cystic fibrosis patients, new β-lactam candidates were studied. Among the abundant library of β-lactams prepared, mainly with antioxidant and antibacterial double activities, it was identified a single lead to be pharmacologically tested in vivo. Its synthesis was optimized up to the gram-scale, and pretreatment method and HPLC-MS/MS analytical protocol for sub-nanomolar quantifications were developed. Furthermore, replacement of acetoxy group in 4-acetoxy-azetidinone derivatives was studied with different nucleophiles and in aqueous media. A phosphate group was introduced and the reactivity exploited using different hydroxyapatites, obtaining biomaterials with multiple biological activities. Following the same kind of reactivity, a small series of molecules with a β-lactam and retinoic hybrid structure was synthesized as epigenetic regulators. Interacting with HDACs, two compounds were respectively identified as an inhibitor of cell proliferation and a differentiating agent on steam cells. Additionally, in collaboration with Professor L. De Cola at ISIS, University of Strasbourg, some new photochemically active β-lactam Pt (II) complexes were designed and synthesized to be used as bioprobes or theranostics. Finally, it was set up and optimized the preparation of new chiral proline-derived α-aminonitriles through an enantioselective Strecker reaction, and it was developed a chemo-enzymatic oxidative method for converting alcohols to aldehydes or acid in a selective manner, and amines to relative aldehydes, amides or imines. Moreover, enzymes and other green chemistry methodologies were used to prepare Active Pharmaceutical Ingredients (APIs).

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Lourenço, Ana Sofia Casanova. "Fucopol as encapsulating matrix of bioactive compounds." Master's thesis, ISA/UL, 2015. http://hdl.handle.net/10400.5/8514.

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Mestrado em Engenharia Alimentar - Instituto Superior de Agronomia
FucoPol is an exopolysaccharide produced by the Enterobacter A47, using glycerol byproduct from the biodiesel industry as carbon source. In this work, the potential of this biopolymer to produce microparticles and to encapsulate bioactive compounds by spray drying was studied. The particles were characterized in terms of morphology (Scanning Electron Microscopy), crystallinity (X-Ray Diffraction), chemical characteristics (Fourier Transform Infrared), and thermal properties (Thermogravimetric Analysis and Differential Scanning Calorimetry). FucoPol was able to form spherical microcapsules (size from 0.5 to 26.7 μm) with a thin wall (thickness from 222 to 1094 nm) and a smooth surface. A population of small particles with dented surfaces was obtained. The microcapsules presented an amorphous structure. Gallic acid (GA) and oregano essential oil (OEO) were encapsulated using FucoPol as wall material. The bioactive loading was 12.2 wt.% and 3.1 wt.% for OEO and GA, respectively. Additionally, the encapsulation efficiency was 20% for OEO and 5.3% for GA. The release profile in simulated gastric (SGF) and intestinal (SIF) fluids revealed a total release, except for the GA in SGF, where 68% retention was observed. The compounds antioxidant capacity was not affected by the encapsulation process. From the results obtained, FucoPol reveals a good potential as microcapsules forming and encapsulating material

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Khadhraoui, Boutheina. "éco-extraction assistée par ultrasons des plantes médicinales : mécanisme(s), intensification et industrialisation ULTRASOUND TECHNOLOGY FOR FOOD PROCESSING, PRESERVATION AND EXTRACTION Histo-cytochemistry and scanning electron microscopy for studying spatial and temporal extraction of metabolites induced by ultrasound. Towards chain detexturation mechanism Microscopic imaging as a tool to target spatial and temporal extraction of bioactive compounds through ultrasound intensificationUltrason. Review of Alternative Solvents for Green Extraction of Food and Natural Green solvents for analytical chemistry." Thesis, Avignon, 2019. http://www.theses.fr/2019AVIG0715.

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Le retour à la naturalité a favorisé le développement des compléments alimentaires à base de ressources végétales qui apparaissent comme un réservoir quasi-infini de nutriments et de substances naturelles bioactives. Ceci fait de l’extraction solide/liquide une étape incontournable au sein des industries intéressées par ce type de molécules. Avec les préoccupations environnementale set sociétales, il est devenu nécessaire d’inventer et développer de nouveaux procédés qui répondent aux six principes de l’éco-extraction. Cette démarche a totalement inspiré cette thèse qui a pour principal objectif le développement d’une technique d’éco-extraction assistée par ultrasons en substitution de la technique conventionnelle. Ce travail a permis de montrer qu’il était possible d’intensifier l’extraction de composés d’intérêt en utilisant les ultrasons avec une meilleure sélectivité et de meilleurs rendements d’extraction. Une attention particulière a été accordée à la compréhension des mécanismes d’action des ultrasons via une étude macroscopique et microscopique approfondie des structures végétales. Cette investigation a prouvé que les ultrasons agissent différemment en fonction des structures végétales et de leurs propriétés morphologiques et chimiques qui leur confèrent un degré de résistance plus ou moins important face à l’action des ultrasons. Partant de ces résultats, l’étude macroscopique et microscopique a été définie comme un outil de décision pour une extraction ciblée. Cette variabilité a été aussi constatée à l’échelle industrielle prouvant davantage l’importance de l’analyse microscopique. Enfin, le procédé d’extraction par ultrasons a été adopté à l’échelle industrielle pour ses performances d’extraction et pour son empreinte environnementale significativement réduite par rapport au procédé CV. Ce travail a également conduit à des travaux complémentaires sur l’étude du potentiel de solubilisation des produits naturels en vue d’une utilisation pour l’extraction de composés végétaux difficiles à solubiliser dans l’eau. Des résultats prometteurs ont été obtenus en termes de pouvoirs de solubilisation et d’extraction notamment à partir de la matière végétale broyée. Les résultats de cette dernière partie soulèvent cependant des questions qui pourraient faire l’objet de futures recherches et de perspectives pour ce travail qui sont principalement liés à l’étude des problèmes liés au changement du solvant et au prétraitement de la matière première et de la faisabilité industrielle de ce nouveau procédé
With recent trends in the increasing interest to environmental, economic and safety considerations,extraction techniques have largely focused on finding solutions with sustainable and green values toimplement in food processing, cosmetic and pharmaceutical industries. In this context, new “green”extraction techniques were developed such as Ultrasound-Assisted Extraction (UAE). The mainobjective of this thesis is industrial implementation of this new process in substitution to theconventional (CV) process. It has been shown in this work that the extraction of compounds ofinterest from rosemary and other plant matrices could be intensified using ultrasound, and thatdifferent performance gain could be achieved according to the plant matrix structural properties.Indeed, macroscopic and microscopic investigation of untreated and treated raw materials provedthat US act through different mechanisms and its resulting impacts can be extremely limited by plantstructural morphological and chemical properties, especially those of the specialized structures.Significant variability in performance gain was also observed at the industrial scale. Overall, USappears as a promising technique with a significant performance gain in terms of extraction yield andselectivity. Moreover, this process presents low environmental footprint compared to the CV one.Finally, it has been shown that natural products, such as honey and fruit juices, can be used toimprove solubilization and extraction of molecules that are poorly soluble in water. Encouragingresults were obtained in terms of solubilization and extraction abilities, especially from ground rawmaterials. However, these results raise questions related to the feasibility of industrialimplementation of this new process

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Beggs, Louise Barbara. "Food-derived bioactive peoptides : potential biological significance." Thesis, University of Ulster, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.529561.

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Casanova, Vallvé Ester. "Modulation of muscle energy metabolism by bioactive compounds." Doctoral thesis, Universitat Rovira i Virgili, 2013. http://hdl.handle.net/10803/127636.

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L’objectiu d’aquesta tesis es desenvolupar una nova estratègia preventiva i terapèutica que requereixi les mínimes modificacions dels hàbits dietètics simultàniament efectiva en contra de l’obesitat i les seves malalties associades. Per aquest estudi s’han seleccionat compostos alimentaris presents en una dieta sana on el seus efectes beneficiosos han estat documentats tant en la obesitat com el risc de patir malalties cardiovasculars. S’inclou els polifenols com l’epigallocatechin gallate (EGCG) i les proantocyanidines i també els àcids grassos poliinsaturats omega 3 (PUFAs) o l’àcid docosahexaenoic (DHA). El treball esta enfocat en el funcionament mitocondrial del múscul, el teixit mes important de l’organisme en el control del balanç de nutrients. Els nostres resultats indiquen que hi ha una millora postprandial amb un increment de la capacitat d’oxidació dels àcids grassos millorant el perfil lipídic i la flexibilitat metabòlica.
El objetivo principal de esta tesis es desarrollar una nueva estrategia preventiva y terapéutica que requiera les mínimas modificaciones de los hábitos dietéticos simultáneamente efectiva en contra de la obesidad y sus enfermedades asociadas. Para este estudio se han seleccionado compuestos alimentarios presentes en una dieta sana dónde sus efectos beneficiosos han estado documentados tanto en la obesidad como en el riesgo de desarrollar enfermedades cardiovasculares. Se incluyen los polifenoles como el epigalocatequin galato (EGCG) y las proantocianidinas; también los ácidos grasos poliinsaturados omega 3 (PUFAs) y el acido docosahexaenoico (DHA). El trabajo está enfocado en el funcionamiento mitocondrial de musculo, el tejido más importante del organismo en el control del balance de nutrientes. Nuestros resultados indican que hay una mejora postprandial con un incremento de la capacidad de oxidación de los ácidos grasos mejorando el perfil lipídico y la flexibilidad metabólica.
The global goal of the present thesis is the development of a new preventative and therapeutic strategy that requires only minor modifications of dietary habits and simultaneously effective against obesity and its major associated diseases. For this study, we have selected food ingredients characteristic in healthy diets which has been documented beneficial effects on obesity or cardiovascular disease risk. These include plant polyphenols, epigallocatechin gallate (EGCG) and proanthocyanidins as well as the sea fish omega-3 polyunsaturated fatty acids (PUFAs) and docosahexaenoic acid (DHA). Our work is focused on the mitochondrial function of skeletal muscle, a major player in the body’s overall nutrient balance, and adipose tissue, which is the key regulator of energy homeostasis in the organism affected by obesity and related diseases. Our results indicate a postprandial improvement with an increase of the fatty acid oxidation capacity, improving lipid profile and metabolic flexibility.

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47

Vahidi, Hossein. "Isolation and production of bioactive compounds from basidiomycetes." Thesis, University of Strathclyde, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249826.

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48

Lincoln, Ruth Andrea. "Studies on bioactive compounds from algae and cyanobacteria." Thesis, University of Hertfordshire, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303440.

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49

Pinheiro, Angela Maria de Marques Lopes e. Ferreira. "" Study of Bioactive Compounds of Marine-Derived Fungi"." Dissertação, Instituto de Ciências Biomédicas Abel Salazar, 2010. http://hdl.handle.net/10216/62177.

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50

Eaton, Alexander Lee. "Isolation and Synthesis of Bioactive Compounds from Plants." Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/64367.

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Abstract:

As a part of a continuing search for bioactive compounds with the International Cooperative Biodiversity Group (ICBG), and in collaboration with the Natural Products Discovery Institute of the Institute for Hepatitis and Virus Research (IHVR), twelve plant extracts were investigated for their antiproliferative activity against the A2780 cell line, three plant extracts were investigated for their antimalarial activity against Plasmodium falciparum, and three plant extracts were investigated for their anti-inflammatory activity (PPAR-y inhibition). Bioassay-guided fractionation of extracts led to the identification of four new antiproliferative compounds (2.1-2.3, 3.1), five new anti-inflammatory compounds (6.4a, 6.5a-b, 6.6a, 6.6c), and twenty-eight known compounds from eight of the extracts. In addition, mallotojaponin C, an antimalarial natural product, and derivatives were synthesized and investigated for their antimalarial activity.
Ph. D.

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Dissertations / Theses on the topic 'Bioactive compounds of food'

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