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Williams, Richard James. "Enzyme assisted self-assembly." Thesis, University of Manchester, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.496231.
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Self-assembling peptide systems provide a pathway for the formation of complex molecular assemblies from relatively simple designed molecules. Stimuli which have been used to trigger the self-assembly (SA) process in aqueous conditions include temperature, pH, ionic strength, and solvent exchange. Additionally, enzymes may be used to selectively control the self-assembly process; enzymes are uniquely chemo-, regio-, and enantioselective, and work naturally under mild conditions without disrupting biological Interactions.
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Hughes, Meghan. "Peptide nanomaterials : characterisation of enzyme-assisted self-assembly." Thesis, University of Strathclyde, 2012. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=18209.
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tan, yi. "Enzyme Catalyzed and Ultrasound Assisted Transformation of Selected Pollutants." FIU Digital Commons, 2017. http://digitalcommons.fiu.edu/etd/3220.
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The widespread use of synthetic drugs and as feed additives has resulted in the release of large amounts of biologically active chemicals into the environment. Exposure to environmentally relevant concentrations of chemicals can have severe effects on human health. Therefore, effective degradation of these synthetic, biologically active compounds is of paramount importance.
Diphenhydramine (DPH) has been selected as a target compound for ultrasound remediation. The results demonstrated that ultrasound-induced degradation has potential applications in managing aqueous media contaminated with DPH.
Atorvastatin and roxarsone have been selected as representative substrates for chloroperoxidase (CPO) catalyzed transformation of pollutants. These studies demonstrate atorvastatin and roxarsone can be degraded efficiently by CPO. The transformation products of each compound were identified and the mechanisms of CPO catalysis postulated. This study provides a foundation for assessing the feasibility of applying CPO in the remediation of water and soil contaminated with pharmaceuticals and feed additives.
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Kuuranne, Tiia. "Anabolic steroid glucuronides : enzyme-assisted synthesis and liquid chromatographic-mass spectrometric analysis." Helsinki : University of Helsinki, 2003. http://ethesis.helsinki.fi/julkaisut/mat/farma/vk/kuuranne/.
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Campbell, Kerry Alan. "Protein and oil recoveries from enzyme-assisted aqueous extraction of soybeans and sunflower seed." [Ames, Iowa : Iowa State University], 2010. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3403074.
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Kapasakalidis, Petros G. "Enzyme assisted extraction of antioxidant phenols and anthocyanins from blackcurrant (Ribes nigrum L.) press residues." Thesis, University of Reading, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433443.
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Kalathoor, Roschni [Verfasser]. "Quantitative and Enantioselective Analyses Following Enzyme Assisted Processes in Soil: Degradation and Non-extractable Residue Formation of the Fungicide Metalaxyl / Roschni Kalathoor." München : Verlag Dr. Hut, 2016. http://d-nb.info/1103872990/34.
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Li, Yuxiu. "Technology of enzyme extraction of Gynostemma pentaphyllum saponins and studies on its hypoglycemic activity." Магістерська робота, Kyiv National University of Technology and Design, 2021. https://er.knutd.edu.ua/handle/123456789/19271.
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In this master's thesis, the composition of saponins in extracts of Gynostemma pentaphyllum obtained by enzymatic extraction has been determined. The HPLC method was used for the simultaneous analysis of hypenosides in medicinal plant materials of different periods and places of growth. The results showed that the highest content of hypenosides was noted in August, the lowest in May; the composition and content of hypenosides from different production zones in the same growing season were different. The optimal parameters of extraction using hypenosidase are as follows: the time of enzymatic hydrolysis is 100 minutes, the temperature of enzymatic hydrolysis is 45℃, the concentration of pectinase is 2 mg/ml. During the extraction process, pectinase transformed the saponins of gynostemma pentaphyllum, making them easier to isolate from plant cells. It has been proven that gynostemma saponins inhibit the activity of alpha-glycosidase with an inhibition rate of more than 90% compared to acarbose and have the effect of lowering blood sugar levels.<br>У цій роботі визначено склад сапонінів в екстрактах Gynostemma pentaphyllum, отриманих шляхом ферментативної екстракції. Метод ВЕРХ використано для одночасного аналізу гіпенозидів у лікарській рослинній сировині різних періодів і місць зростання. Результати показали, що найвищий вміст гіпенозидів відмічений у серпні, найменший у травні; склад і вміст гіпенозидів з різних зон виробництва в одному вегетаційному періоді були різними. Оптимальні параметри екстракції за допомогою гіпенозидази такі: час ферментативного гідролізу 100 хвилин, температура ферментативного гідролізу 45℃, концентрація пектинази 2 мг/мл. Під час процесу екстракції пектиназа трансформувала сапоніни Gynostemma pentaphyllum, завдяки чому їх легше було виділити з рослинних клітин. Доведено, що сапоніни гіностеми пригнічують активність альфа-глікозидази зі швидкістю інгібування більше ніж на 90% порівняно з акарбозою та впливають на зниження рівня цукру в крові.
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Liang, Pingping. "Gold Nanoparticle-Based Colorimetric Sensors for Detection of DNA and Small Molecules." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/2595.
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Biosensors have proven to be a powerful tool for detecting diverse targets, such as proteins, DNA, and small molecules representing disease biomarkers, toxins, drugs and their metabolites, environmental pollutants, agrichemicals, and antibiotics with high sensitivity and specificity.
The major objective of the research described in this dissertation was to develop low cost, low sample volume, highly sensitive and specific AuNP-based colorimetric sensor platforms for the detection of DNA and small molecules. With this in mind, we propose an instrument-free approach in chapter three for the detection of NADH with a sensor constructed on a paper substrate, based on the target-induced inhibition of AuNP dissolution. The successful detection of this important molecule opens the door to numerous possibilities for dehydrogenase characterization, because NAD+/NADH are essential cofactors for more than 300 dehydrogenase enzymes. To further increase the sensitivity of our hybridization-based assay for DNA detection, we developed an enzyme-assisted target recycling (EATR) strategy in chapter four and have applied such an EATR-based colorimetric assay to detect single-nucleotide mismatches in a target DNA with DNA-functionalized AuNPs. This assay is based on the principle that nuclease enzymes recognize probe–target complexes, cleaving only the probe strand. This results in target release, enabling subsequent binding to and cleavage of another probe molecule. When the probe is conjugated onto AuNPs, complete cleavage from the AuNP surface produces a detectable signal in high ionic strength environments as the nanoparticles undergo aggregation. With such enzyme-assisted amplification, target detection can occur with a very low nM detection limit within 15 minutes. The extent of DNA loading on the AuNP surface plays an important role in the efficiency of DNA hybridization and aptamer-target assembly. Many studies have shown that high surface-coverage is associated with steric hindrance, electrostatic repulsive interactions and elevated surface salt concentration, whereas low surface-coverage can result in nonspecific binding of oligonucleotides to the particle surface. In chapter five, we investigated DNA surface coverage effects, and apply this optimization in conjunction with a highly-specific aptamer to develop a sensitive colorimetric sensor for rapid cocaine detection based on the inhibition of nuclease enzyme activity.
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Fournière, Mathilde. "Extraction et évaluation des propriétés biologiques des ulvanes et oligo-ulvanes de l'algue verte Ulva sp. : actions sur le métabolisme de cellules cutanées et sur le microbiote cutané." Electronic Thesis or Diss., Lorient, 2021. http://www.theses.fr/2021LORIS593.
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Les ulvanes sont des polysaccharides matriciels sulfatés constitutifs de la paroi de l’algue verte Ulva sp.. Bien que proliférative et quantitativement disponible, Ulva sp. est peu valorisée avec des applications dans des domaines à faible valeur ajoutée. Ce projet de thèse a pour objectif la production de fractions enrichies en ulvanes et en oligo-ulvanes dans le but d’évaluer leurs propriétés biologiques sur le système cutané. Les fractions d’ulvanes ont été produites par macération et extraction assistée par enzyme suivie de différents procédés de purification : précipitation éthanolique et dialyse. Des dépolymérisations radicalaire et acide ont permis d’obtenir des fractions d’oligo-ulvanes. Ces fractions d’ulvanes et d’oligo-ulvanes stimulent la prolifération de fibroblastes dermiques humains. Une augmentation de la synthèse protéique de composants matriciels dont les collagènes de type I et III, et les glycosaminoglycanes a été mise en évidence. Les fractions stimulent également l’expression, la synthèse et l’activité enzymatique de MMP-1. Au niveau du microbiote cutané, ces fractions n’altèrent pas la croissance des bactéries commensales S. epidermidis, S. aureus et C. acnes, mais peuvent modifier la formation de biofilm. Les fractions d’ulvanes et d’oligo-ulvanes diminuent également le potentiel inflammatoire des kératinocytes HaCaT induit par C. acnes. Ainsi, les travaux ont démontré que les fractions d’ulvanes et d’oligo-ulvanes présentent des activités biologiques prometteuses pour des applications dermo-cosmétiques dans le cadre de stratégies de réparation tissulaire, anti-vieillissement, ou anti-inflammatoire, dans le respect du microbiote commensal cutané<br>Ulvans are matrix sulfated polysaccharides constitutive of green seaweed Ulva sp. cell wall. Although proliferative and quantitatively available, Ulva sp. is little valued with applications in low added value sectors. The objective of this project is to produce fractions enriched in ulvans and oligo-ulvans in order to evaluate their biological properties on cutaneous system. Ulvan fractions were produced by maceration and enzyme-assisted extraction followed by different purification processes: ethanolic precipitation and dialysis. Radical and acid depolymerization processes allowed to obtain oligo-ulvan fractions. Ulvan and oligo-ulvan fractions have been shown to stimulate human dermal fibroblasts proliferation. An increase in the synthesis of extracellular matrix components such as type I and III collagens, and glycosaminoglycans has been demonstrated. Fractions also stimulate the expression, synthesis and MMP-1 enzymatic activity. At the skin microbiota level, the fractions do not alter the growth of commensal bacteria S. epidermidis, S. aureus and C. acnes, but may modify the biofilm formation. Ulvan and oligo-ulvan fractions also reduce the inflammatory potential of HaCaT keratinocytes induced by C. acnes. Thus, this work has shown that the ulvan and oligo-ulvan fractions exhibit promising biological activities for dermo-cosmetic applications in tissue repair, anti-ageing or anti-inflammatory strategies while preserving commensal skin microbiota
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Wilhelm, Kelsey. "A Systematic Review of Hyaluronidase‐Assisted Subcutaneous Fluid Administration in Pediatrics and Geriatrics and Its Potential Application in Low Resource Settings." Thesis, The University of Arizona, 2017. http://hdl.handle.net/10150/623621.
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A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine.<br>The role of enzyme‐assisted subcutaneous fluid administration (EASFA) in treating mild to moderate dehydration in pediatrics, geriatrics, and palliative care has been studied in developed countries. However, it has historically been underutilized due to widely available health care and alternative treatments, namely peripheral intravenous (IV) fluid administration. Fluid infusions in the subcutaneous tissue have a low risk of infection, are easy to administer, and have wide potential use. The use of EASFA in low resource settings to treat those with difficult IV access or where skilled healthcare workers are not as readily available could prove to be a live saving measure in many situations, including the care of patients in remote areas of the world, mass casualty events, or other disasters. Our objective was to determine if EASFA is a valid and appropriate technique to utilize in pediatric and elderly patients, and evaluate if it could be a safe and efficient way to provide fluid resuscitation in low resource settings. For this systematic review MEDLINE and Cochrane Library were searched from January 1950 to December 2015 to recover all available literature relevant to this topic. Studies that met the inclusion criteria were analyzed using Cohen’s D. This was calculated using the mean difference between intervention and control divided by the pooled standard deviation. For dichotomous outcome of the placement success rate the odds ratios were calculated with 95% confidence intervals. In reviewing 7 articles using Cohen’s D to compare mean differences to determine effect size, we found that catheter placement success rates and infusion rates were similar between EASFA and peripheral intravenous fluid administration. Additionally, it was found that the odds of correct initial needle placement was 7.19 times higher in EASFA versus intravenous administration. EASFA is a comparable alternative to intravenous fluid administration when delivering fluids to pediatric and elderly patients with mild to moderate dehydration. While infusion rates and total volume of fluids administered were similar, the high rate of success with placement of the subcutaneous catheter proves it to be more useful in some situations. Venous cannulation is difficult, even for a trained healthcare provider, and the ease of placement of subcutaneous catheters makes training lay people to administer subcutaneous fluids a possibility. Additionally, this type of fluid administration may lead to less psychological trauma to a child from multiple needle sticks, while still achieving a similar outcome of effective volume replacement. Based on the results of this study, further research is needed to evaluate the effectiveness of utilizing EASFA in low resource settings.
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Lu, Chunmeng. "Development of novel micro-embossing methods and microfluidic designs for biomedical applications." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1156820643.
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Hardouin, Kévin. "Production d'extraits aqueux à partir d'Ulva sp, au moyen de procédés d'hydrolyse enzymatique : caractérisatin, valorisation et perspectives de développement." Thesis, Lorient, 2015. http://www.theses.fr/2015LORIS373.
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Ces travaux de thèse CIFRE, réalisés au sein du Laboratoire de Biotechnologie et Chimie Marines de l’Université de Bretagne-Sud et du Groupe Olmix, s’inscrivent dans le cadre d’un projet national de valorisation de biomasses d’algues vertes, le projet ULVANS. Ce projet est le fruit d’une collaboration entre cinq industriels bretons et deux laboratoires universitaires. Les objectifs de ces travaux de thèse concernent i) la caractérisation approfondie de la matière première, en particulier des polysaccharides matriciels solubles (ulvanes) et des protéines, ii) la mise au point d’un procédé d’extraction assistée par enzymes des métabolites algaux, iii) la caractérisation biochimique et moléculaire des hydrolysats enzymatiques, avec pour objectif la compréhension de l’effet des enzymes commerciales sur les algues, iv) l’évaluation des activités antioxydantes et antivirales des hydrolysats, v) l’étude de l’influence des paramètres d’hydrolyse en vue de déterminer les conditions optimales pour l’extraction des métabolites d’intérêt et enfin vi) de conclure, à partir des éléments fournis par l’étude, sur la viabilité d’un tel procédé à l’échelle industrielle. En conclusion de ces travaux, l’hydrolyse enzymatique apparait comme un procédé intéressant pour le bioraffinage des algues vertes. Bien que les préparations enzymatiques commerciales utilisées ne soient pas spécifiques des composés algaux, les protéases ont conduit à une augmentation significative des rendements d’extraction, alors que l’effet des carbohydrases reste modéré. L’étude de l’influence des paramètres d’hydrolyses a confirmé les résultats préliminaires et montré que la température, la concentration d’enzyme et la méthode de broyage présentaient peu d’effets sur les activités des protéases testées. Un résultat majeur de cette étude aura été la mise en évidence d’activités anti-herpétiques dans les hydrolysats. La caractérisation des fractions actives a montré que les activités étaient liées à la présence de protéines ou glycoprotéines dans les extraits. Ce résultat présente un intérêt majeur car à l’heure actuelle, a priori, aucune activité de ce type n’a été identifiée chez Ulva sp<br>This PhD Thesis works, conducted in the Laboratoire de Biotechnologie et Chimie Marines of the Université de Bretagne-Sud and in the Olmix Group, was included in a national project for the upgrading of green seaweed biomasses, the Ulvans project. This project results in the collaboration of five industrial companies and two academic research laboratories. The objectives of this thesis works had been i) the characterization of the raw material, particularly the soluble matrix polysaccharides (ulvans) and proteins, ii) the development of an enzyme-assisted extraction process of algal metabolites, iii) the biochemical and molecular characterization of the enzymatic hydrolyzates, with the aim of understanding the effect of enzymes on algae thallus, iv) the screening of antioxidant and antiviral activities of hydrolyzates, v) the study of the influence of hydrolysis parameters to determine the optimum conditions for the extraction of metabolites of interest and finally vi) to conclude, according to the results provided by this study, on the viability of the industrial upscaling of the process. In conclusion of this work, enzymatic hydrolysis appeared to be an effective process for biorefinery of green seaweeds. Although commercial enzymatic preparations were not specific of algal compounds, protéases led to a significant increase in the extraction yields, whereas the effect of carbohydrases were moderate. The study of hydrolysis parameters confirmed the preliminary results and showed that the temperature, the concentration of enzyme and the grinding method had no effect on the protease used. A major result of this study has been the highlighting of anti-oxidant and anti-herpetic compounds in hydrolyzates. The antiviral activity of ulvans had several times been demonstrated but the biochemical characterization of actives fractions showed that the activity could be associated to proteins or glycoproteins. This result is very interesting because, a priori, any antiviral activity has also been related to this type of compounds in Ulva sp
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Davidson, Morag. "Éco-extraction de composés bioactifs à partir de marcs de fruits rouges & étude de leur impact sur l'homéostasie intestinale." Electronic Thesis or Diss., Limoges, 2024. http://www.theses.fr/2024LIMO0020.
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Depuis 2010, 100 millions de tonnes de fruits rouges sont produits chaque année dans le monde. 20% de déchets résultent de leur 1ère transformation industrielle, comprenant les graines et les peaux, appelés marcs. L’épandage et l’alimentation animale constituent leurs principales voies de valorisation, alors qu’ils peuvent être une source potentielle de composés bioactifs hydrophiles (fibres, protéines, polyphénols, oligo-éléments) et lipophiles (acides gras polyinsaturés, phytostérols, tocols). Par conséquent, il devient intéressant de concevoir des procédés d’extraction simultanée de l’ensemble de ces biomolécules pour exploiter pleinement les activités biologiques qui leurs sont associées.Le travail de cette thèse s'est fixé deux objectifs majeurs. Tout d'abord, développer un procédé d'éco-extraction innovant, combinant l’utilisation d’enzymes et d’ultrasons pour extraire, simultanément et en milieu aqueux, les composés hydrophiles et lipophiles des marcs de fruits rouges. Ensuite, évaluer in vitro les propriétés prébiotiques des extraits obtenus.Les différents travaux de la thèse se sont articulés autour de quatre phases successives : (i) la caractérisation chimique des marcs de framboise, de fraise, de mûre et de cassis, (ii) le développement du ou des procédé(s) d’éco-extraction, (iii) la caractérisation chimique globale des « éco-extraits » obtenus et (iv) l’évaluation in vitro de leur activité prébiotique potentielle.Le développement du procédé d’éco-extraction des composés d’intérêt à partir des quatre marcs de fruits s’est déroulé en trois étapes. Tout d'abord, trois enzymes (un mélange de glycohydrolases, une protéase acide et une protéase alcaline) ont été testées seules ou combinées séquentiellement. Ensuite, les systèmes enzymatiques sélectionnés ont été associés à des ultrasons, soit simultanément (enzyme + ultrasons) soit de manière séquentielle (enzyme → ultrasons ou ultrasons → enzyme). Le choix des systèmes enzymatiques et de leurs combinaisons avec les ultrasons s'est basé sur leur efficacité, leur facilité d'utilisation et leur caractère novateur par rapport aux travaux existants. Enfin, les combinaisons retenues ont été optimisées à l'aide d'un plan d'expérience (Definitive Screening Design) en ajustant six paramètres comprenant chacun trois niveaux : amplitude des ultrasons, pH, ratio enzyme/substrat, ratio solide/liquide, durée et température.La combinaison simultanée « protéase alcaline-ultrasons » a été retenue et optimisée pour les marcs de framboise, de fraise et de mûre. Elle a permis d’extraire, dans un solvant aqueux et en une seule étape, la totalité de leurs composés phénoliques, ayant préservé 75% de leur capacité antioxydante, ainsi que 75% de l’huile présente dans ces marcs. Concernant le marc de cassis, la combinaison simultanée « protéase acide-ultrasons » optimisée a permis l’extraction de 75% des polyphénols totaux (dont la totalité des anthocyanes), ainsi que 50% de l’huile.Les extraits obtenus ont également démontré des propriétés prébiotiques, favorisant la croissance de bactéries probiotiques (Lactobacillus plantarum 299v, Lactobacillus rhamnosus), les positionnant comme des candidats potentiels pour l'industrie nutraceutique. Ils pourraient être intégrés dans des compléments alimentaires visant à maintenir ou rétablir l'équilibre du microbiote intestinal<br>Since 2010, 100 million tons of red fruits have been produced globally each year. 20% of wastes result from their first industrial transformation, which includes the seeds and the skins, known as pomace. While spreading and animal feeding are common ways to valorise these wastes, they are also a potential source of hydrophilic and lipophilic bioactive compounds (fibres, proteins, polyphenols, minerals & poly-unsaturated fatty acids, phytosterols, tocols). Therefore, it is interesting to design simultaneous extraction processes to extract simultaneously all of these biomolecules to fully exploit their biological activities.This thesis aimed to achieve two goals. The first goal was to develop an innovative extraction process by combining the use of an enzyme(s) with the use of ultrasounds to extract simultaneously, in an aqueous medium, the hydrophilic and lipophilic bioactive compounds of red fruit pomaces. The second goal was to assess in vitro the prebiotic properties of the extracts.The thesis was divided into four successive steps: (i) the characterisation of the proximate compositions of the raspberry, strawberry, blackberry and black currant pomaces, (ii) the design of one or several eco-extraction process(es), (iii) the global chemical characterization of the “eco-extracts” and (iv) the in vitro assessment of their potential prebiotic properties.The design of the eco-extraction process was divided into three steps. First, three enzymes (a cocktail of glycohydrolases, an acid protease and an alkaline protease) were tested, alone or sequentially combined. Secondly, the selected enzymatic systems were associated with ultrasounds, either simultaneously (enzyme + ultrasounds) or sequentially (enzyme → ultrasounds and ultrasounds → enzyme). The choice of the enzymatic system(s) and their combination with ultrasounds was based on their extraction efficiencies, ease of implementation and innovative character compared to existing literature. Finally, the selected combination(s) were optimised by an experimental design (Definitive Screening Design) by adjusting six parameters comprising three levels: ultrasound amplitude, pH, enzyme/substrate ratio, solid/liquid ratio, extraction time and temperature.The simultaneous combination “alkaline protease-ultrasounds” was selected and optimised for the raspberry, strawberry and blackberry pomaces. All of the polyphenols, with 75% of their antioxidant capacities, and 75% of the oil present in the pomaces were extracted in a single step in an aqueous medium. The optimised simultaneous combination “acid protease-ultrasounds” extracted 75% of the polyphenols, with the totality of the anthocyanins, and 50% of the oil of the black currant pomace.The eco-extracts demonstrated prebiotic properties towards probiotic bacteria (Lactobacillus plantarum 299v, Lactobacillus rhamnosus) by favouring their growth. This makes them potential candidates for the nutraceutical industry. The eco-extracts could be integrated into dietary complements to maintain or restore the intestinal microbiota balance
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Salwiński, Aleksander. "Development of novel mass spectrometry-based approaches for searching for low-mass tyrosinase inhibitors in complex mixtures." Thesis, Orléans, 2014. http://www.theses.fr/2014ORLE2013/document.
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Ce manuscrit de thèse présente le développement de méthodes basées sur la spectrométrie de masse consacrées à la recherche d'inhibiteurs d'enzymes en milieux complexes, tels que les extraits de plantes. L’enzyme Tyrosinase a été utilisé comme principale cible biologique du fait de son implication dans les processus d’hyperpigmentation cutanée. De ce fait, la recherche d’inhibiteurs de cette enzyme, présente un grand intérêt pour l'industrie cosmétique. La première partie de ce manuscrit décrit la mise en place de la chromatographie d'affinité frontale (FAC), permettant d’obtenir le classement simultané des inhibiteurs présent dans un mélange complexe en fonction de leurs affinités avec la cible biologique. Deux capillaires hydrophiles de phase monolithiques ont été évalués afin de réduire au maximum les interactions non spécifiques indésirables entre les analytes et le support solide d’immobilisation. De plus, nous avons étudié la faisabilité de l’utilisation de phases à base de silice comme support solide d’immobilisation des enzymes dans le cadre de ces analyses par chromatographie d'affinité frontale. La seconde partie du manuscrit de thèse est consacrée au développement et à l’optimisation de l’approche nommée ENALDI-MS (Enzyme-coupled Nanoparticles-Assisted Laser Desorption/Ionisation Mass Spectrometry) permettant d’accéder à une gamme des faibles masses (m/z 500 Da). Elle est déclinée en une première approche dite par ‘extinction d’ions’ (Ion Fading, IF-ENALDI), basée sur l’identification directe de la liaison des inhibiteurs vis-à-vis de l’enzyme sans pré-traitement de l’échantillon végétal. Une seconde déclinaison de l’ENALDI-MS concerne une approche dite par ‘Ion Hunting’ (IH - ENALDI MS), basée sur une méthode de pré-concentration sélective des inhibiteurs présents dans l'échantillon<br>This thesis report presents the development of mass spectrometry-based methods for searching for inhibitors of enzymes in complex mixtures, such as plant extracts. Tyrosinase enzyme was used as the main biological target for the reason of a significant importance of its inhibitors in the cosmetic industry as the skin whitening agents. The first part of this report describes Frontal Affinity Chromatography (FAC), an approach enabling simultaneous ranking the inhibitors within the complex mixture according to their affinities to the biological target. Two hydrophilic capillary-scale polymer-based bioaffinity stationary phases were evaluated in the context of the presence of undesirable nonspecific interactions between the analyte and the solid immobilisation support. In addition, we explored the usability of two types of silica-based particles as a solid support for enzyme immobilisation for FAC. The second part of the thesis manuscript is devoted to Enzyme-coupled Nanoparticle-Assisted Laser Desorption/Ionisation Mass Spectrometry (ENALDI MS) as a low-mass compatible extension of the Intensity ion Fading MALDI MS (IF-MALDI MS) method for high-throughput screening of the inhibitors in the complex mixtures. Two variations of ENALDI MS were evaluated: 'Ion Fading' (IF-ENALDI MS), based on on-the-spot binding of inhibitors by enzyme molecules and 'Ion Hunting' (IH-ENALDI MS), based on selective pre-concentration of inhibitors present in the sample
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Orrling, Kristina M. "On the Versatility of Microwave-Assisted Chemistry : Exemplified by Applications in Medicinal Chemistry, Heterocyclic Chemistry and Biochemistry." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-101356.
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Vigier-Carriere, Cécile. "Surface assisted self-assembly of peptides." Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAE013/document.
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Depuis quelques années, la modification de surface est une méthode efficace qui permet de contrôler les interactions entre un matériau et son environnement. Ce domaine de recherche ouvre la voie au développement de nouvelles surfaces « intelligentes » aux propriétés fonctionnelles. Dans ce manuscrit, nous présentons la conception d’un revêtement capable de contrôler l’auto-assemblage de peptides exclusivement à la surface d’un matériau. L'auto-assemblage est initié par un stimulus enzymatique localisé à la surface qui permet la transformation de peptides précurseurs en peptides gélateurs, ayant la propriété de s’auto-assembler pour former des structures fibrillaires enchevêtrées pour former un hydrogel. Les surfaces enzymatiques ont été obtenues par adsorption d’enzyme spécifique en utilisant la méthode « couche par couche ». Dans une première approche, la croissance du réseau de fibres est initiée par accumulation d’oligopeptides (KL)nOEt confinés sur un film enzymatique d’α-chymotrypsine. Ce processus d’hydrogélation peut être contrôlé dans le temps (en ajustant le temps de latence) en changeant la concentration en peptides KLOEt et la densité de surface en enzyme. Dans une deuxième approche, le film multicouche bioactif contenant l’alcaline phosphatase a été fonctionnalisé par une couche d’ensemencement composée d’acide poly(acrylique) modifié par une séquence peptidique Fmoc-FFC aux propriétés gélatrices. La modification de la densité de peptides gélatrices en surface a permis de contrôler le processus d’auto-assemblage du peptide gélateur Fmoc-FFY depuis la surface. Lorsque le film bioactif est mis en contact avec le peptide précurseur, i.e. Fmoc-FFY(PO42-) substrat de l’alcaline phosphatase, le peptide gélateur se forme et s’auto-assemble sous forme de nanofibres à partir de la surface. Grâce à ces deux études nous avons démontré qu'un film précurseur enzymatique ou une couche bioactive d'ensemencement sont des matériaux permettant d’initier et de contrôler l’auto-assemblage de peptides en surface afin de former un hydrogel<br>Since the middle of the last century, the functionalization of surfaces has emerged as a convenient method to control interactions between a material and its surrounding environment. This recent research field paves the way to the design of surfaces bearing original “smart” functionalities. Herein, we present the design and control of peptide self-assembly taking place exclusively at or near a surface in response to an enzymatic stimulus. The localized enzyme-assisted self-assembly (LEASA) of peptides led to the growth of micrometric hydrogels from the surface. The enzymatic surface was obtained by adsorption of specific enzymes using the layer-by-layer method. In a first strategy, we developed the growth of fibrillary networks resulting from the accumulation of oligopeptides (KL)nOEt produced from a confined enzymatic layer of α-chymotrypsine at the interface. This process of gelation was tuned in time (lag time) by controlling the peptide KLOEt concentration and the enzymatic surface density. In a second strategy, alkaline phosphatase was embedded into a multilayer film to obtain a bioactive surface on which a seed-layer, i.e a poly(acrylic acid) covalently modified with a hydrogelator peptide, was adsorbed. This layer allows to control the self-assembly of the fiber network by changing the peptide density anchored on the seed layer. When this bioactive and seeding film is brought into contact with the peptide substrate, i.e. Fmoc-FFY(PO42-), of alkaline phosphatase, an efficient self-assembly of Fmoc-FFY is obtained leading to nanofibers growing from the surface. We demonstrated that an enzymatic precursor film or a more sophisticated bioactive seeding layer can self-instruct the self-assembly of small peptides sequences and influence buildup of a micrometric hydrogel from the surface
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Yu, Dajun. "Ultrasound-assisted enzymatic extraction of protein hydrolysates from brewer's spent grain." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/97875.
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Brewer's spent grain (BSG) is the most abundant by-product of the brewing industry and its main application is limited to low-value cattle feed. Since BSG contains 20 to 25% of proteins, it has the potential to provide a new protein source to the food industry. In this research, an ultrasound-assisted enzymatic extraction was designed to extract protein hydrolysates from BSG. Original BSG and ultrasound pretreated BSG were hydrolyzed under different enzyme (Alcalase) loadings and incubation times. Centrifugation was applied to separate solubilized proteins from insoluble BSG residue. When the enzyme loading increased from 1 to 40 uL /g BSG, the solubilized proteins increased from 34% to 64.8%. The application of ultrasound further increased the solubilized proteins from 64.8% to 69.8%. Solubilized proteins from ultrasound pretreated BSG was significantly higher (p < 0.05) than that from the original BSG. Particle size distribution analysis showed that the application of ultrasound pretreatment reduced the BSG particle size from 331.2 to 215.7 um. Scanning electron microscopy images revealed that the BSG particle surface was partially ruptured by the ultrasound pretreatment. These two phenomena might have contributed to the increased protein separation efficiency with ultrasound pretreatment. The solubility (pH 1.0 to 11.0) of protein hydrolysate increased by the application of ultrasound and the ultrasound did not lead to the change of the amino acid composition of the separated protein hydrolysates. Based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis profile, the protein was degraded to peptides which had molecular weights lower than 15 kDa. The color of the separated protein hydrolysates by enzymatic hydrolysis was brighter and lighter than the original BSG. The application of ultrasound did not affect the color of the separated protein hydrolysates. Overall, the ultrasound pretreatment prior to enzymatic hydrolysis enhanced the extraction of proteins from BSG in terms of higher protein separation efficiency, lower enzyme loadings, and reduced incubation time. This study developed a novel and green method to effectively extract value-added protein hydrolysates from the low-value food processing byproducts.<br>MSLFS
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Battistini, Matthew R. "Novel Enzyme Perspectives: Arylalkylamine N-acyltransferases from Bombyx mori & 1-Deoxy- D-Xylulose-5-Phosphate Synthase from Plasmodium falciparum and Plasmodium vivax." Scholar Commons, 2015. http://scholarcommons.usf.edu/etd/5908.
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This dissertation is dedicated to the research and investigation of novel enzymes and the methods used to study them, with physiological roles ranging from isoprenoid biosynthesis to neurotransmitter production. Using a combination of bioinformatics, recombinant cloning, enzymology, and proteomics, we have contributed to the understanding and exploration of several human illnesses, including malaria, cancer, and endocrine dysfunction.
Our first project involved studying the enzymes responsible for N-acylarylalkylamide biosynthesis in Bombyx mori. Very little is known how these potent signaling molecules are produced in vivo, however, one possible pathway is the direct conjugation of an acyl-CoA to a corresponding arylalkylamide by the enzyme arylalkylamine N-acyltransferase (AANAT). In insects, this enzyme is responsible for controlling melanism, the inactivation of biogenic amines, the sclerotization of the insect cuticle, photoperiodism, and the penultimate intermediate in the production of melatonin. We studied a pair of AANAT enzymes from B. mori: Bm-AANAT and Bm-AANAT3. The former was found to catalyze the direct formation of long-chain acylarylalkylamines (only the second enzyme discovered to do such chemistry), while the latter exhibited potent inactivation of several amines through acetylation. We conducted a full kinetic characterization of Bm-AANAT3, including double-reciprocal plots, pH-rate profiling, dead-end inhibition, and the construction of mutants to elucidate catalytically-relevant amino acids. Our hope is that new insights and discoveries on these enzymatic pathways in model organisms will yield novel molecular targets for human health and disease.
We then developed an innovative, microwave-assisted synthesis of a binding-based probe capable of enriching proteins that bind adenine ribose derivatives (AdoRs). We employed this probe in activity-based protein profiling studies to qualitatively assess the AdoR-binding proteome in three bacterial cell lines from the genus Bacillus. This proof of concept experiment demonstrated a unique subset of proteins distinctive to each species, and confirmed the efficacy of the probe tagging and subsequent enrichment. This technology can be used in clinical applications for the detection and identification of cancerous biomarkers.
Finally, we successfully truncated and recombinantly-expressed 1-deoxy-D-xylulose-5-phosphate synthase (DXS) from both P. vivax and P. falciparum. We elucidated the order of substrate binding for both of these TPP-dependent enzymes using steady-state kinetic analyses, dead-end inhibition, and intrinsic tryptophan fluorescence titrations. Both enzymes adhere to a random sequential mechanism with respect to binding of both substrates: pyruvate and D-glyceraldehyde-3-phosphate. These findings are in contrast to other TPP-dependent enzymes, which exhibit classical ordered and/or ping-pong kinetic mechanisms. A better understanding of the kinetic mechanism for these two Plasmodial enzymes could aid in the development of novel DXS-specific inhibitors that might prove useful in treatment of malaria.
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Riemenschneider, Leif [Verfasser]. "Enzyme assisted nanolithography / Leif Riemenschneider." 2004. http://d-nb.info/975489771/34.
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SHEHAB, SARAH ANNE. "AN INVESTIGATION OF ENZYME-ASSISTED VITRECTOMY." Thesis, 1986. http://hdl.handle.net/1911/16011.
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Surgical vitreous removal (vitrectomy) is increasingly advocated to diminish the undesired consequences of retinal damage, which frequently arises from disease or injury to the vitreous. Current surgical techniques for vitrectomy use mechanical or ultrasonic devices that fragment and aspirate the vitreous from the eye. Because of the close proximity and attachment of the vitreous to the retina, this procedure itself incurs a high risk of inflicting retinal damage. Therefore, a less hazardous procedure for total vitrectomy is clinically desirable.
This project primarily focuses on the use of enzymes as an adjunct to vitrectomy. Injected into the vitreous a few minutes prior to vitrectomy, the enzymes disrupt the structural integrity of the vitreous macromolecules and vitreo-retinal junction, making vitrectomy a less hazardous procedure.
To investigate the effect of the enzymes on the vitreous, it was necessary to quantify changes in the rheological properties of the vitreous resulting from enzyme action. Three experimental schemes were devised for this purpose: firstly, a modified capillary viscometer was built in our laboratory. Secondly, vitrectomy instrumentation was used, and the time for total vitrectomy was measured in enzyme or control eyes. Lastly, a fluids rheometer was used to measure the elastic and viscous moduli and dynamic viscosity of enzyme or control eyes. The incidence of retinal damage caused by the enzymes was also estimated.
The results showed that the most effective enzymes were chymopapain and chondroitinase ABC, which required short pretreatment times (20 minutes) and relatively low dose levels (10 and 0.6 mg/ml respectively). Both reduced the vitrectomy time by up to 61% of the controls and neither enzyme produced significant numbers of retinal detachments. Indeed, it was observed that chymopapain effected a clean detachment of the vitreous from the retina. Fluids rheometer experiments revealed that the mechanism by which these two enzymes assist vitrectomy is different.
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Wang, Yu-Wei, and 王毓瑋. "Study of microwave-assisted protein digest in an immobilized enzyme reactor." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/30174940324703512980.
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ZENG, JING-FEN, and 曾靜芬. "Enzyme-assisted Extraction of Phenolic Compounds From Kumquat and Its Biological Activities." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/z7f89b.
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碩士<br>國立宜蘭大學<br>食品科學系碩士班<br>106<br>Kumquat is one of the important agricultural crops in Yilan. It is well known that kumquat have anti-microbial, antioxidant and tyrosinase inhibitory activities, which might because of the presence of phenolic compounds. Therefore, effective extraction of phenolic compounds from kumquat could promote the application and its additional commercial value. Enzymes-assisted extraction method can increase the extraction yield of phenolic compounds, and also reduce the solvent usage and lowering environment risk. Thus, the aim of this study was to develop extraction method by enzyme-assisted to increase the extraction yield of phenolic compounds from kumquat. The bioactivities of the extracts will be also evaluated and was provided for the industry application.
Immature kumquat (Fortunella japonica var. margarita) was treated by three different enzymes (Cellulase、Pectinase and Viscozyme L), individually. Then, the resulted hydrolysate will be dried and extracted by hot water. The total phenolic content was determined. The result showed that the highest total phenolic content was observed of treatment by Viscozyme L. Furthermore, the optimal Viscozyme L treatment conditions were determined by following factors: enzyme / substrate ratio (0.05, 0.1, 0.25 and 0.5), reaction temperature (40, 45, 50 and 55oC), pH (4.0, 4.5, 5.0 and 5.5), and reaction duration (6, 12, 18 and 24 hours). The results indicated that the highest total phenolic contents could be obtained by treatment with Viscozyme L at 0.1 (E/S), pH 5.0, reaction temperature 45 oC for 18 hours. The total phenolic content increased about 27% and ORAC also increased 28%, when compared with these in hot water extracts (HWE). However, its antibacterial and tyrosinase inhibitory activity decreased. Meanwhile, the flavonoids composition decreased drastically. The main decreasing flavonoids was 3′, 5′-di-C--glucopyranosylphloretin (DGPP). On the contrary, the content of phenolic acid increased significantly.
In order to elucidate the effect of pH value on flavonoid compositions, the flavonoid compositions of the extracts of kumquat was investigated at acid (pH 3.7) and neutral (pH 6.8) environment. Results showed that, flavonoid compositions is higher at acid (pH 3.7) environment than at pH 6.8. Moreover, re-adjusted the pH value and reaction time to pH 4.5 for 6 hours, the flavonoid composition increased to 4356 mg / 100g by Viscozyme L treatment, which was higher than HWE (4075 mg / 100g). The content of phenolic acid could also increase to about 3.4 times (6.79 mg / 100. -coumaric, -hydroxybenzoic, vanillic and ferulic acid were the predominant phenolic acid in kumquat. The release of phenolic acids indicated that the cell wall might be destroyed after treatment by Viscozyme L. However, its antibacterial activity decreased after treatment with Viscozyme L except against to B. cereus.
In addition, ultrasonic incubation, instead of oscillation, combined with enzyme assisted extractions for 2 hours could increase extraction of flavonoid compositions to 4909 mg / 100 g, about 20% more than extraction by HWE. The extracted amount is higher than extraction by Viscozyme L for 6 hours (4356 mg / 100g). This hinted that ultrasonic treatment could effectively shorten the extraction time. The antioxidant activity of ORAC and DPPH scavenging potency increased for 54% and 150%, respectively. Besides, tyrosinase inhibitory activity increased also from 85.79% to 93.36%. Although the content of phenolic acid could be enhanced to 5.53 mg / 100g, its value still lower than treated by Viscozyme L for 6 hours.
Collectively, in condition of this study, the highest phenolic compounds of immature kumquat could be obtained, by ultrasonic incubation combined with Viscozyme L assisted extraction under E/S 0.1, pH 4.5, at 45oC for 2 hours.
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NAIR, ADITHYA. "ENZYME ASSISTED AQUEOUS EXTRACTION OF VEGETABLE OIL AND ENZYMATIC TREATMENT OF VEGETABLE OIL MILL EFFLUENT." Thesis, 2018. http://dspace.dtu.ac.in:8080/jspui/handle/repository/16422.
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Vegetable oil represents a major share in the global consumable fats and oil produced. The major types of vegetable oil produced are Palm oil, Soybean oil, Canola oil etc. with palm accounting for more than 30% of the entire production. Conventional oil extraction steps include mechanical and solvent extraction. An alternative for these conventional steps of oil extraction is the aqueous enzymatic extraction, here the solvent used for extracting the oil is water and thus it minimises the many environmental hazards posed by solvent extraction. The enzymatic extraction involves use of a combination of hydrolytic enzymes to degrade the plant cell wall components and make the oil accessible for aqueous extraction. The major classes of enzymes include, cellulases, xylanases, proteases etc. This research work focuses on enzymatic aqueous extraction and its various parameter optimisation which include, dosage studies, oil loss analysis, and down streaming techniques like centrifugation. The dosage analysis shows the optimum dosage for effective enzymatic activity on the substrate. The enzymatic aqueous extraction is not as efficient as the solvent extraction hence oil loss studies are important to calculate the enzymatic efficiency, and this is done using Soxhlet analysis. Microscopic analysis of the substrate treated with enzyme is useful for understanding the enzymatic activity. The downstreaming of the extracted oil is also a vital step in getting higher oil yields and thus optimisation studies for centrifugation steps was carried out. These studies include, rotor type analysis and rcf value analysis for optimum oil yield. The effluent coming from the mills have high BOD and COD. The effluent is also rich in a lot of complex sugar polymers. Biogas production from effluent has an enormous potential in tackling various environmental problems including lowering greenhouse gas emission. The anaerobic digestion of effluent can be enhanced using the enzymes to break down complex polymers to soluble monomers that can be readily metabolized by methanogenic bacteria. The use of enzyme on effluent resulted in increase in the concentration of glucose and this was confirmed using DNS assay and HPLC. This further supports the idea of using enzymes in effluent treatment and suggests immense potential of enzymatic treatment of the effluent. Further research must be carried out for making this viable on an industrial scale.
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Zhang, Hao kai, and 張皓凱. "The Effects of Microwave-Assisted Pretreatment and Enzyme Loading to the Production of Xylooligosaccharides from Rice Straw." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/85890290468562434133.
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碩士<br>明新科技大學<br>化學工程與材料科技系碩士班<br>101<br>Agricultural residues are rich in lignocellulose. Lignocellulose is composed of cellulose, hemicellulose, and lignin. When treated and converted properly, lignocelluloses can be transformed into useful value-added products.
Xylooligosaccharide is a high value functional food that can be derived from hemicelluloses via partial hydrolysis. In this study, xylooligosaccharide was prepared from rice straw by a series of treatments including microwave-assisted alkali treatment, ethanol precipitation and enzyme hydrolysis. Taguchi’s design of experiments was adopted to study the influence of process variations, including the concentration of sodium hydroxide (0.2%, 0.5%, 0.8 %), the reaction temperature (180 oC, 190 oC, 200 oC) and the reaction time (1 min, 3 min, 5 min) in microwave assisted pretreatment, and enzyme loading (30U/g, 50U/g, 70U/g), and the target was to maximize the production of xylooligosaccharide. It is found that xylooligosaccharide production was maximized under the process variable combination of 0.5 % NaOH, 200 oC, 3 min and 50 U/g.
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Senanayake, S. P. J. Namal. "Enzyme-assisted synthesis of structured lipids containing long-chain omega-3 and omega-6 polyunsaturated fatty acids /." 2000.
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Tsai, Chuang-Wei, and 蔡創韋. "Develop a low power microwave-assisted enzyme digestion platform for efficient detection of bioactive peptide using mass spectrometry." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/jg88ze.
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碩士<br>國立中興大學<br>分子生物學研究所<br>102<br>The bioactive peptide Val-Val-Tyr-Pro (VVYP) can be genetically modified into dietary supplements which functions in reducing the triglyceride in blood and thus aid in preventing obesity, coronary heart disease and cardiovascular diseases. Dietary supplements are usually digested by various enzymes in the intestinal tract hence cause the production of functional peptides. Previous studies showed microwave-assisted system can highly improve the hydrolysis efficiency and it is timesaving. Besides, microwave-assisted method with high power usually produces lots of unpredicted miss-cleavage peptides resulting higher sequence coverage arises from longer peptides. However, this situation causes the predicted target peptides cannot be quantified. Therefore, the analysis of genetically modified VVYP storage protein of soy bean glycinin (Gy) using strategy of bi-enzyme coupled with low power microwave-assisted system is introduced to develop the best analysis platform via HPLC-ESI-SRM. By using trypsin and carboxypeptidase B (CPB), Gy1 and Gy5 will release 7 sets and 10 sets of VVYP respectively. With this strategy, a platform with high efficiency and high recovery rate for the analysis of VVYP in Gy1 and Gy5 is expected. In the future, this platform can be applied on detecting and quantifying health foods as well as protein drugs.
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Yeh, Yu-Cheng, and 葉祐成. "Studies on the physicochemical properties of mucilage from the seed of Citrus grandis Osbeck with enzyme or enzyme combined with ultrasonic assisted extraction and its application in edible film." Thesis, 2019. http://ndltd.ncl.edu.tw/cgi-bin/gs32/gsweb.cgi/login?o=dnclcdr&s=id=%22107NCHU5253035%22.&searchmode=basic.
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碩士<br>國立中興大學<br>食品暨應用生物科技學系所<br>107<br>Mucilage is a hydrocolloid, mainly composed of polysaccharide. It is applied to the modification of food properties. In previous studies, there is an abundant pectin-like mucilage in seed coat of Citrus grandis Osbeck. Therefore, the purpose of this study is to characterize the physicochemical properties of mucilage of Citrus grandis Osbeck seed through enzymatic and ultrasonic extraction methods. The results showed that the yield increased after enzymatic or ultrasonic treatment. Especially celluclast combined with ultrasound, it could significantly increase the yield and the highest yield group was celluclast extraction followed by ultrasound (7.63%). In monosaccharide compositions analysis, the galacturonic acid content of buffer extraction was 83.36% and it decreased after enzymatic and ultrasonic treatment. The celluclast extraction would increase the galactose and mannose content. Then, the cellulase extraction would increase the glucose content. In intrinsic viscosity and molecular weight, the enzymatic and ultrasonic extraction both decreased significantly, especially cellulase extraction. However, there is no significant influence in degree of esterification (72~77%).
In mucilage edible film, the buffer extraction mucilage of edible film has high transparent and high hydrophilic properties. It would decrease transparence and become hydrophobic by celluclast extraction or celluclast extraction followed by ultrasound. In addition, the buffer extraction mucilage has excellent tensile strength (74.68 MPa), and puncture strength (5.22 N) but the celluclast extraction or celluclast extraction followed by ultrasound would decrease the tensile strength. Moreover, the emulsified edible film become more hydrophobic accompanied with the mechanical properties decreased. The celluclast extraction or celluclast extraction followed by ultrasound decrease the glass transition temperature and then the emulsified edible film has lowest Tg (-4.15℃). According to above results, the mucilage of Citrus grandis Osbeck seed has potential to be a thickener or a substitute source of pectin. Its mucilage edible film exhibits excellent mechanical properties and can combine with other biological sources to improve its hydrophilic properties in the future.
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CHIH, CHIH-HSIUNG, and 陳智雄. "Development of Two Enzyme-Assisted Spectrophotometric Method for Quantification of Ascorbic Acid in beverages Using Bicinchoninic Acid (BCA) or ABTS." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/40770795994438115607.
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碩士<br>長庚大學<br>醫學生物技術研究所<br>94<br>Ascorbic acid(Vitamin C) play a pivotal role as an antioxidant which is essential for the health of the human body.For this reason,it is a routine practice of supplementing ASA in the beverages.Two enzyme-assisted spectrophotometric methods for the determination of ASA in beverages has been developed.The precision data of these two methods as reflected by within-run and day-to-day CVs for low,medium and high QC specimens are all＜5.0％.The results obtained by these two methods correlate excellently with the established capillary electrophoretic method with correlation coefficients of 0.90(for BCA) and 0.93(for ABTS) methods.Actual determinations of ASA concentrations in 18 well-knowns beverages in Taiwan have been assessed.The results were correlated excellently with those determined by capillary electrophoretic method.These data indicate that our two proposed method are suitable for the future utilization in the determination of ASA in beverages.It can be easily adapted by every laboratory.
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Chen, Ciao-Yun, and 陳巧芸. "Study on Enzyme-Assisted Productions of Phycobiliproteins from Gracilaria tenuistipitata and Mixed Agaro-Oligosaccharides from Gracilaria tenuistipitata Residue and Their Bioactivities." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/36bam9.
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碩士<br>國立臺灣海洋大學<br>食品科學系<br>107<br>This study is aim to investigate purification and storage of phycobiliproteins from Gracilaria tenuistipitata produced by enzyme-assisted hydrolysis and analyze characteristic and bioactivities of mixed agaro-oligosaccharides from Gracilaria tenuistipitata residue. Using G. tenuistipitata to induce marine bacteria Pseudomonas vesicularis MA103 and Aeromonas salmonicida MAEF108 could produce crude enzymes of agarase, amylase, cellulase, xylanase, ι-carrageenase, λ-carrageenase, and κ-carrageenase. Total enzymatic activities were 13.77 U/mL which produced by MA103 in 3 days, and were 3.49 U/mL which produced by MAEF108 in 2 days. G. tenuistipitata solution was hydrolyzed by crude enzymes solution of 15% MA103 and 15% MAEF108 (M3M8) and 30% MA103 (M3) for 48 hr after homogenizing and ultrasonication. The fluorescence intensity (FI) of phycoerythrin (PE) of M3M8 and M3 increased 19.7 fold and 23.1 fold than control, respectively, and phycocyanin (PC) increased 1.8 fold and 1.9 fold, respectively. Further, G. tenuistipitata hydrolyzed solution by crude enzymes solution were removed < 30 kDa by ultrafiltration (UF) system, and using gel filtration column differentiated by fast protein liquid chromatography (FPLC) to acquire PE, PC, and allophycocyanins (APC). The purity index (PI) of PE, PC, and APC of M3M8 were 3.8, 1.3, and 1.8, respectively and M3 were 3.7, 1.1, and 1.4, respectively. SDS-PAGE chromatogram were shown G. tenuistipitata solution was hydrolyzed by crude enzymes solution and their fractions were α, β (20 kDa) and γ (35 kDa) subunits. In storage test, 4oC was better storage temperature to keep the concentration and fluorescence intensity of PE, 26oC was better storage temperature to keep the concentration of PC and APC, and -80oC was better storage temperature to keep the FI of PC and APC. Moreover, using ion exchange column differentiated by FPLC to acquire PE, and their PI of M3M8 and M3 were both 0.7, and then their fractions were removed < 30 kDa by UF. Using gel filtration to purified the fractions by FPLC, the PI of PE fractions of M3M8 and M3 were 4.4 and 4.3, respectively, and yield were 0.78% and 0.76%, respectively. Using agar to induce marine bacteria P. vesicularis MA103 and A. salmonicida MAEF108 could produce crude enzymes of agarase, activities were 2.97 U/mL and 2.59 U/mL which produced by MA103 and MAEF108 in 2 days, respectively. Mixed agaro-oligosaccharides were gained from G. tenuistipitata residue (GAOS3K) that treated by hot water (121oC/20 min), then collected by UF (< 3 kDa). The yield of GAOS3K-M3M8 and GAOS3K-M3 were 0.62% and 0.66%; The content of sulfate were 10.05% and 9.57%; The content of total phenols were equal to 209.08 and 201.50 μg/mL GAE equivalent. Thin layer chromatography (TLC) chromatogram were shown degree of polymerization (DP) of GAOS3K-M3M8 and GAOS3K-M3 mainly DP 2, DP 4, and DP 6. High performance liquid chromatography (HPLC) chromatogram were shown MW of GAOS3K-M3M8 and GAOS3K-M3 mainly 1,023 Da oligosaccharides, and conjectured DP 6. Fourier transforminfrared spectroscopy (FT-IR) spectra of GAOS3K-M3M8 and GAOS3K-M3 is presented C-O-S, C-O-H, and C-C. In antioxidative activity assays, the DPPH scavenging activity of GAOS3K-M3M8 and GAOS3K-M3 (10 mg/mL) were 27.57% and 40.79%; The Fe2+ chelating ability of GAOS3K-M3M8 and GAOS3K-M3 (5 mg/mL) were 97.36% and 97.38%; The reducing power of GAOS3K-M3M8 and GAOS3K-M3 (10 mg/mL) were equal to 34.0549 and 40.4223 µg/mL Trolox equivalent. In anticoagulant activity assays, which are activated partial thromboplastin time (APTT) and prothrombin time (PT) using rabbit plasma, GAOS3K-M3M8 could prolong the aggregation time and decrease the aggregation level compared to blank. GAOS3K-M3 could prolong the aggregation time and decrease the aggregation level compared to blank in PT and thrombin time (TT) test. The effect of GAOS3K-M3M8 and GAOS3K-M3 on cell viability for B16-F10 cells were both above 85%, and decreased melanin content of B16-F10 cells to 48% and 43%. The tyrosinase inhibition activities of GAOS3K-M3M8 for B16-F10 cells was 14% (10 min), and GAOS3K-M3 was 23% (50 min). Therefore, these results indicated that GAOS3K could perform antioxidative, anticoagulant, and whitening activities.
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Li, Zong-Yu, and 李宗育. "UV Light-Assisted Synthesis of Polyadenosine-Stabilized Gold Nanoclusters for Ratiometric Fluorescent Sensing of Hg(II), Enzyme Activity, and Target Nucleic Acid." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/zp3d46.
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碩士<br>國立中山大學<br>化學系研究所<br>103<br>DNA sequence has been used in synthesis of silver nanoclusters that play a role of template in decade in decade. The DNA-templated silver nanocluster has been widely applied at sensing of metal ion, biomolecular and bio-image. But there is a challenge in synthesis of gold nanoclusters by using DNA sequence as a template.
In this study, we develop a new approach that UV light-assisted, facile, one-pot, NaBH4-free and boundary way to synthesize gold nanoclusters by using poly-adenosine as a template, and get the poly-adenosine stabilized gold nanoclusters that have an emission at 475 nm under the excitation of 280 nm. Under a series of experiment, we definit the UV light play an important role in reduction reaction of gold ion by citrate ion. In size-exclusion chromatogaph(SEC), we can find the structure of poly-adenosine is more compact after the formation of poly-adenosine stabilized gold nanoclusters, it provide an evidence that poly-adenosine is a stabilizer for preventing gold atom aggregate into gold nanoparticles and forming of gold nanoclusters. On the other hand, we design a sequence contain poly-adenosine and specific DNA sequence to synthesize a poly-adenosine stabilized gold nanoclusters of containing specific DNA sequence, and it can combine with SYBR GREEN I to provide a ratiometric fluorescent sensors. This ratiometric fluorescent sensors provide a sensitivie and selective detection for specific DNA sequence, thiol-relative enzyme and mercury ion by hybridization of DNA, etching of thiol and metallophilic interactions, and successfully used in real sample.
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Shih, Yung-Han, and 施詠漢. "Novel green research:1.Rapid synthesis of chromatographic stationary phases.2.Metal-organic frameworks as enzyme reactors and matrixes in surface assisted laser desorption/ionization." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/67dmp8.
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博士<br>中原大學<br>化學研究所<br>101<br>In this dissertation, development of novel synthesis approach and the application of porous metal-organic frameworks are the purposes based on green research.
In the first part of this study, ionic liquid 1-hexyl-3-methylimidazolium tetrafluoroborate ([C6mim][BF4]) was used as reaction medium to prepare three common monolith materials including methacrylate ester-, styrene- and mixed methacrylate ester/styrene-based polymers either by water bath at 100℃or by microwave heating. Instead of volatile organic solvents, the usage of [C6mim][BF4] as reaction medium was more efficient for both reactions, the vinylization of column inner-wall and the monolith syntheses, which are the most time-consuming steps in conventional monolithic material preparation. When [C6mim][BF4] was used as reaction medium, the vinylization of fused silica capillary was achieved within 5 min, while ~20 h is required with conventional solvents (e.g. methanol). Furthermore, the reaction time for fabricating polymeric monolith was obviously reduced from 20 h (conventional method) to 5 min when IL solvent was used. In order to demonstrate the feasibility of these rapid synthetic methods, monoliths were employed as the separation columns for capillary electrochromatography (CEC) and nanoscale liquid chromatography/mass spectrometry (nano-LC/MS) in the separation of aromatic compounds, the qualitative and quantitative performances were comparable with the monoliths prepared by conventional approaches.
In the second part of this study, dicyclohexylcarbodiimide was used to activate the free carboxylate groups on the metal-organic frameworks (MOFs) to an effective leaving group, and then reacted with trypsin via nucleophilic attack, finally the trypsin was immobilized onto MOFs (herein referred as trypsin-MOF) which was applied in protein digestion. The trypsin digested BSA peptides generated via the trypsin-MOFs reactors were analyzed by nano-LC/MS2 followed by the database searching for amino acids sequence coverage and matched peptides, confirmed the performance of these trypsin-MOFs. Based on the results, the amino acids sequence coverage and the number of matched peptides 69% and 41 for reusable trypsin-MIL-88B-NH2(Cr) under ultrasonic assisted digestion (2 min), which could be substituted for the traditional trypsin in-solution digestion (i.e. free trypsin with 18 h digestion). In contrast to the native MOFs using terephthalic acid (1,4-BDC) as ligands (MIL-101(Cr) and MIL-88B(Cr)), an amine-functionalized MOFs with NH2-1,4-BDC as ligand (MIL-88B-NH2(Cr)) exhibited increased efficiency for protein digestion ability possibly due to the increased hydrophilicity and better bio-compatibility which did not only reduce the undesired nonspecific adsorption of proteins also enhanced the enzyme immobilization and protein digestion efficiency.
In the last part of this study, the cage-type (MIL-100(Fe), MIL-100(Cr), MIL-100(Al), MIL-101(Cr)) and the channel-type (DUT-4, DUT-5, CYCU-3) MOFs were chosen as matrixes in surface assisted laser desorption/ionization mass spectrometry (SALDI-MS) for analysis of polycyclic aromatic hydrocarbons (PAHs). In contrast to those PAHs using tradition organic matrix (α-cyano-4-hydroxycinnamic acid), background interference from the MOFs matrixes was very low or even disappeared for channel and cage MOFs, respectively. And the signal variance was the lowest when MIL-100(Fe) as matrix for analysis of PAHs, for example, the relative standard deviations (RSDs) of signal intensity with three replicated analyses were between 2.00%-16.33% for shot-to-shot assay. The results and the absence of background noises from the MS spectra suggested no ‘sweet spot’ problem resulted from the use of MIL-100(Fe) as matrix. Lastly, MIL-100(Fe) was used as solid-phase-extraction (SPE) adsorbent to trap trace-level PAHs (1 mg/L) in under ground water samples and as matrix for SALDI-MS analysis of PAHs in the same time. Hence, the limit of detection was lower from 1.16-11.41 ng/μL to 0.007-0.031 ng/μL without and with SPE, respectively.
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Chiang, Chia-Fang, and 江佳芳. "Effect of enzyme-assisted extraction in combination of ultrasound treatment on the physicochemical properties of mucilage from the fronds of Asplenium australasicum （J. Sm.） Hook." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/z956uc.
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碩士<br>國立中興大學<br>食品暨應用生物科技學系所<br>106<br>Enzyme-assisted extraction (EAE) possess the advantages of being environmentally friendly and easily operated owing to relatively mild reaction conditions while ultrasound-assisted extraction (UAE) owns high frequency and strong penetration that both of EAE and UAE are considered to be the innovative and green extraction technology. Therefore, in this study, mucilage from Aspenlenium australasicum was first extracted by xylanase, glucanase and a combination of these two enzymes, followed by ultrasound treatment. The effects of enzyme and ultrasound treatment on the physicochemical properties of the mucilage were investigated including basic composition, monosaccharide composition, polysaccharide functional groups, molecular weight distribution, intrinsic viscosity, rheological properties, water and oil holding capacity, and glucose dialysis retardation index.
It was observed that compared to the control, the yield of mucilage increased significantly by EAE and UAE (from 3.64% to 6.04~7.47%). SEM results showed that enzymes can erode the raw material which contributed to the higher yield of mucilage, especially in assisted with ultrasound. The FT-IR fingerprint did not change pronouncedly due to the action of the enzymes and ultrasound, which meant they wouldn’t destroy polysaccharide structure. In monosaccharide composition, the ratio of uronic acid to neutral sugar is about 3:17, which galacturonic acid is approximately 4~5 times that of glucuronic acid while galactose, glucose and fucose were primary neutral sugar. Compared with the control group, the content of galacturonic acid and glucose increased significantly after EAE. It could be the change of monosaccharide composition and the complexity of polysaccharide branching that significantly reduced the intrinsic viscosity and the glucose dialysis retardation index of the mucilage. EAE mucilage possessed higher molecular weight, but after UAE, the polysaccharide branches were degraded by ultrasound, which in turn reduced the molecular weight and increased the intrinsic viscosity. Further studies on rheological properties found that in steady shear test, mucilage from Aspenlenium australasicum was non-Newtonian fluid with shear thinning property while frequency sweep showed that G’ and G” increased with increasing concentration, and G’ was higher than G” (gel-like) in the concentration of 6%. However, both G’ and G” decreased after UAE, indicating that ultrasound treatment would reduce gelling capacity of the mucilage. The water holding capacity of the EAE mucilage was slightly lower than the control but increased after UAE, while there was no significant difference in oil holding capacity. As compared to other dietary fibers, the mucilage from Aspenlenium australasicum still showed good water and oil holding capacity.
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Huang, Si-Ying, and 黃思穎. "Study on the Production Condition of Enzyme-assisted Extraction of Fucooligosaccharides and Fucoxanthin from Laminaria japonica and Their Biological Activity of Antioxidant and Anti-inflammatory." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/zrrdkd.
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碩士<br>國立臺灣海洋大學<br>食品科學系<br>107<br>This aim of this study is to investigate the enzyme-assisted production conditions of fucooligosaccharides (FOS) from Laminaria japonica powder and the enzyme-assisted extraction conditions of fucoxanthin from L. japonica residue, as well as to evaluate their antioxidant activity and anti-inflammatory activity. Firstly, L. japonica fucoidan (LJ-FD) is gained from L. japonica treated by hot acid method, the yield is 18.09% (18.09 g per 100 g L. japonica powder). L. japonica fucoolisaccharides (LJ-FOS3k) is produced by hydrolyzing L. japonica powder with fucosidases which are induced by marine bacteria Pseudomonas vesicularis MA103, Aeromonas salmonicida MAEF108, and transgenic strain Lactococcus lactis NZ3900 rfucI-H. After 3% L. japonica powder is first hydrolyzed by commercial cellulase for 24 hr at pH 6.5 then fucosidases for 72 hr at pH 5.5, ultrafiltration system is used to collect < 3 kDa molecular, and the yield of LJ-FOS3k is 11.74% (11.74 g FOS3k per 100 g L. japonica powder). HPLC chromatogram results showed that there are 2,339 Da (DP 12) and 536 Da (DP 2) olisaccgarides in LJ-FOS3k, and the increased of hydrolysis time, the content of olisaccgarides has an upward trend. Secondly, using L. japonica residue (LJr) obtained from the above experiment to induce strains MA103 and MAEF108, the better total enzyme activities are 7.21 and 1.09 U/mL, respectively, which are produced by MA103 in 2 days and MAEF 108 in 3 days. Hydrolyzing 4% homogenous LJr with 30% (v/v) cude enzyme solution for 48 hr at 26oC, and then extract L. japonica fucoxanthin (LJ-FX) at room temperature (26oC) with 90% acetone, the concentration of FX in extract, quantified by absorbance value, is 6.061 g/mL. After initial separation and HPLC analysis, the yield of FX is 0.49‱ (0.49 mg LJ-FX per 100 g L. japonica powder). In antioxidant activity assays, FD (20 mg/mL), FOS3k (20 mg/mL), and FX (4 g/mL) have 30.42%, 43.95%, and 81.19% of the DPPH scavenging activitiy; 27.95%, 28.68%, and 12.61% of the Fe2+ chelating ability; and the absorbance value of the reducing power (OD700nm) were 0.289, 0.385, and 0.557. In anti-inflammatory assays, the cell viability significantly improved to 60.32-70.29% and 64.10-64.84%, respectively after treated in co-treatment and post-induced with 2 g/mL FOS3k and 2 ng/mL FX on lipopolysaccharides (LPS) induced RAW264.7 cell, while compared to that of the control group (50.14%) (p < 0.05). Compared to control group (24.05 mM), the NO release content significantly decreased 34.73% and 16.17% after treated in co-treatment with 2 g/mL FOS3k and 4 ng/mL FX on lipopolysaccharides (LPS) induced RAW264.7 cell (p < 0.05). FOS3k have anti-inflammatory activity on lipopolysaccharides (LPS) induced RAW264.7 cell when treated in co-treatment with 0.02 g/mL concentration, it can significantly decrease the secretion of TNF-38.63 ng/mL, IL-6 (160.29 ng/mL), IL-10 (8.76 ng/mL) while compared to that of the control group (56.52, 211.02, 25.31 ng/mL) (p < 0.05). Compared to the control group (56.52, 211.02, 25.31 ng/mL), it has anti-inflammatory activity on LPS induced RAW264.7 cell while treated in co-treatment with 4 ng/mL FX, which significantly decrease the secretion of TNF-37.05 ng/mL, IL-6 (109.92 ng/mL), IL-10 (16.85 ng/mL) (p < 0.05). Above all, LJ-FOS3k and LJ-FX obtained from this experiment perform antioxidant and anti-inflammatory activity.
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Tien, Chung-An, and 田仲安. "Purification of Angiotensin I-Converting Enzyme Inhibitory Peptides and the Antihypertensive Effect of Hydrolysate from High Hydrostatic Pressure-Assisted Enzymatic Hydrolysis of Fermented Tilapia Byproduct." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/cr89ya.
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Lee, Yu-Huei, and 李昱慧. "Studies of thermal water-extraction and enzyme-assisted treatment on lowering oil content to improve storage stability of rice bran and preparation of rice bran hemicellulose." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/37042582204684175146.
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碩士<br>國立中興大學<br>食品暨應用生物科技學系所<br>101<br>Rice bran is a common by-product of rice milling process. It contains large amount of starch, oil, protein, dietary fiber, vitamin B, vitamin E and minerals. It is also well-known as carriing abundant functional and bioactive compounds such as γ-oryzanol, tocotrienols and inositol hexaphosphate (phytic acid), which are beneficial as antioxidative agent, hypolipidemic agent and anti-carcinogen. However, the utilization of rice bran is limited because of high lipid content, which is the main cause of rice bran rancidity. The highly active lipase will be released during the rice milling process, and hydrolyzes lipid into free fatty acids and rapidly lead to oxidative rancidity.
In the present study, the optimal condition of thermal water-extraction treatment, which is environmental friendly, to reduce lipid content of rice bran without using organic solvent was investigated. Rice bran was heated to 95℃ after mixing with 15-fold of distilled water, and using aeration and α-amylase hydrolysis to assist in releasing lipid from bran before storage at 4℃ overnight. Through this thermal water-extraction treatment, we expected to remove most of the lipid and starch and extend the shelf-life of rice bran. Subsequently, the defatted rice bran was refined further with flavourzyme, and then treated with NaOH to extract hemicelluloses. Finally, commercial hemicellulases were used to prepare hemicellulose hydrolysate with high oligosaccharide content, and their prebiotic effect was examined.
In the study of thermal water-extraction treatment, the lipid removal rate of rice bran without α-amylase assisting was 67.17±0.23% after discarding the supernatant and emulsions. The lipid removal rate will increase to 72.1±1.72% after repeating thermal water-extraction twice. The lipid removal rate of thermal water-extraction with 0.1% and 0.15% α-amylase-assisted was 49.35±2.41% and 47.41±0.42%, respectively. It increased to 63.32±4.83% and 61.15±0.59% respectively after the second treatment. The lipase activity reduced about 66.59% and 71.35% after treating with thermal water-extraction once and twice, respectively. For defatted rice brans obtained by treating with different thermal water-extraction conditions, they showed great improvement on stability when stored at 4℃, 25℃, 40℃ for 12 weeks.
The yield of rice bran hemicellulose B from rice bran was 13.43±0.1% using 4 M NaOH as extraction solvent. The optimal condition for preparing hemicellulose hydrolysate was adding 1 % (w/v) of Amano hemicellulase to hydrolyze rice bran hemicellulose at 45℃ for 4 hours to obtain the product containing the most of oligosaccharides. On study of prebiotic effect, use of rice bran hydrolysate supplementing with 10% hemicellulose hydrolysate as culture medium could promote the growth of Lactobacillus kefiranofaciens BCRC16059 effectively, which was comparable to that of culturing with MRS broth.
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Chang, Kuo-Chung, and 張國鍾. "Functionalized nano-gold particle assisted enzyme immobilization technique for glucose sensor electrode on-line flow injection analysis and continuous immobilized cellulase hydrolysis of waste bamboo chopsticks." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/10277948154532983674.
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博士<br>中原大學<br>化學研究所<br>101<br>Functionalized nano-gold particles assisted enzyme immobilization has been used for preparations of glucose sensor electrode and immobilized cellulase which have been applied for on-line flow injection analysis (on-line FIA) of glucose from waste bamboo chopsticks powder hydrolysis and continuous hydrolysis of waste bamboo chopsticks powder, respectively. In this study, the HB type pencil lead was used as the material for the new type glucose sensor electrode. The surface of the carbon electrode was modified with carbon paste and gold particles first. Then, L-cysteine was bound to the gold particle on the carbon electrode surface. Finally, the glucose oxidase and mediator was bound to the L-cysteine on the carbon electrode surface with chemical covalent bond. This kind of electrode possessed a wide linear range (0-39.0 mM, r2=0.9956) of glucose standard addition calibration curve, low detection limit (7.8 μM), and fast response time (5 s). The sensitivity was 2212 nA mM-1. The glucose sensor electrode can be used more than 50 days (the longest time was 94 days). This enzyme electrode was coupled to the FIA system through a specifically designed flow cell for on-line monitoring the glucose product from waste bamboo chopsticks hydrolysis by immobilized cellulase. The maximum amount of the glucose produced from the hydrolysis was 0.46 mM at 32 h reaction time. The interference level for the enzyme electrode measurement was 7%, 5%, 0% and 0% for mannose, galactose, cellobiose and xylose, respectively. The technique of the glucose sensor electrode on-line FIA also has good analytical accuracy (94.4-97.7%) and precision (RSD 2.2-4.5%) for glucose measurement. The statistical analysis shows that no obvious systematic error exists between the glucose sensor electrode on-line FIA system and traditional HPLC system for glucose analysis.
Similar enzyme immobilization method as the glucose sensor electrode was also used for the preparation of immobilized cellulase. Silica was activated with hydrochloric acid first. Then, the activated silica was reacted sequentially with (3-mercaptopropyl) trimethoxysilane (3-MPTMS) and nano-gold particles. Thus, L-cysteine can be bound to the nano-gold particle through its thio group. Finally, cellulase was immobilized on L-cysteine modified silica surface through the peptide-bond coupling reagent, N, N’-dicyclohexyl carbodiimide to form the immobilized cellulase. This immobilized cellulase was used to produce glucose by the continuous hydrolysis of waste bamboo chopsticks powder. The optimal conditions for the immobilized cellulase hydrolysis of waste bamboo chopsticks were pH 8.0 and 50C. The continuous hydrolysis of waste bamboo chopsticks powder was performed with an initial 0.3 g L-1 waste bamboo chopsticks powder, a cellulase loading of 40 mg cellulase (g silica)-1, a continuous feed concentration of 0.2 g L-1 waste bamboo chopsticks powder at a continuous feed and draw rate of 0.5 mL min-1, and a reaction period of 4 days. The conversion rates of the repeated continuous hydrolysis of waste bamboo chopsticks powder were 72.0-76.6% and the corresponding total accumulated amounts of glucose were 630.5-671.2 mg which were much better than the batch hydrolysis (45.9% and 137.8 mg). At higher enzyme loading (117 mg cellulase (g silica)-1) the conversion rate was 82.9% and a total amount of 1418 mg glucose. The immobilized cellulase can be recovered easily by filtration. For six repeated continuous hydrolysis cycles for a period of 90 days, the enzyme activity is kept about the same or even better than the initial activity.
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Li, Chi-Hua, and 李季樺. "Purification and Preparation of Angiotensin I Converting Enzyme Inhibitory Peptides and Antihypertensive Effect of Hydrolysate from High Hydrostatic Pressure–Assisted Protease Hydrolysis of Fermented Seabass Byproduct." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/77256q.
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