Academic literature on the topic 'HS-SPME'
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Journal articles on the topic "HS-SPME"
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Guidotti, Maurizio. "Determination of Se4+ in Drinkable Water by Solid-Phase Microextraction and Gas Chromatography/Mass Spectrometry." Journal of AOAC INTERNATIONAL 83, no. 5 (September 1, 2000): 1082–86. http://dx.doi.org/10.1093/jaoac/83.5.1082.
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Abstract A method was developed for the selective determination of Se4+ in drinkable water by solid-phase microextraction (SPME) and gas chromatography/mass spectrometry (GC/MS). Se4+ was selectively derivatized to ethane, 1,1′-selenobis by reaction with sodium tetraethylborate, extracted by the SPME fiber, and determined by GC/MS. Both headspace (HS)–SPME and direct SPME were studied. The method requires only a few milliliters of sample and 20 min for completion. At 2.0 μg/L concentration, the relative standard deviation was 10.1% for HS–SPME and 9.1% for direct SPME. For HS–SPME, the theoretical detection limit was 81 ng/L and 166 ng/L for direct SPME. The recovery rate was 95%. The method was used to determine Se4+ in 10 tap water samples.
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Aggarwal, Prashant, James Baker, Mark T. Boyd, Séamus Coyle, Chris Probert, and Elinor A. Chapman. "Optimisation of Urine Sample Preparation for Headspace-Solid Phase Microextraction Gas Chromatography-Mass Spectrometry: Altering Sample pH, Sulphuric Acid Concentration and Phase Ratio." Metabolites 10, no. 12 (November 25, 2020): 482. http://dx.doi.org/10.3390/metabo10120482.
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Headspace-solid phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) can be used to measure volatile organic compounds (VOCs) in human urine. However, there is no widely adopted standardised protocol for the preparation of urine samples for analysis resulting in an inability to compare studies reliably between laboratories. This paper investigated the effect of altering urine sample pH, volume, and vial size for optimising detection of VOCs when using HS-SPME-GC-MS. This is the first, direct comparison of H2SO4, HCl, and NaOH as treatment techniques prior to HS-SPME-GC-MS analysis. Altering urine sample pH indicates that H2SO4 is more effective at optimising detection of VOCs than HCl or NaOH. H2SO4 resulted in a significantly larger mean number of VOCs being identified per sample (on average, 33.5 VOCs to 24.3 in HCl or 12.2 in NaOH treated urine) and more unique VOCs, produced a more diverse range of classes of VOCs, and led to less HS-SPME-GC-MS degradation. We propose that adding 0.2 mL of 2.5 M H2SO4 to 1 mL of urine within a 10 mL headspace vial is the optimal sample preparation prior to HS-SPME-GC-MS analysis. We hope the use of our optimised method for urinary HS-SPME-GC-MS analysis will enhance our understanding of human disease and bolster metabolic biomarker identification.
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Osman, Rozita. "Optimization of Headspace Solid Phase Microextraction (HS-SPME) for the Extraction of Volatile Organic Compounds (VOCs) in MD2 Pineapple." Science Letters 14, no. 2 (June 1, 2020): 61. http://dx.doi.org/10.24191/sl.v14i2.9543.
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Headspace solid phase microextraction (HS-SPME) was employed for the extraction of volatile organic compounds (VOCs) in MD2 pineapple (Ananas comosus L. var. comosus cv. MD2). Optimisation of HS-SPME operating parameters was conducted using three-factor, three-level Box–Behnken response surface experimental design to evaluate the interactive effects of temperature (30 – 50 ºC), extraction time (10 – 30 min) and salting effect (1 – 3 g of salt addition) on the amount of selected VOCs. Determination of VOCs was done using gas chromatography with spectrometry detector (GC-MSD). Extraction temperature was found to be significant (p < 0.05) in increasing the amount of selected VOCs (ethyl acetate, methyl isobutyrate and butanoic acid methyl ester). Based on the maximum amount of these VOCs, the optimum operating extraction conditions for HS-SPME were set up at temperature of 30 °C, time of 29 min and salt addition of 1 g. The optimized HS-SPME conditions were employed for the extraction of VOCs from pineapple of different varieties.
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Ping, Xian Yin, and Yun Long Wang. "Headspace Solid Phase Microextraction Procedure for the Detection of Polychlorinated Biphenyls in Seawater Sample." Applied Mechanics and Materials 316-317 (April 2013): 383–86. http://dx.doi.org/10.4028/www.scientific.net/amm.316-317.383.
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Headspace solid phase microextraction combined with gas chromatography (HS-SPME–GC) method has been studied for determination of 7 polychlorinated biphenyls (PCBs) in seawater samples. To perform the HS-SPME polydimethylsiloxane (PDMS) (7, 30 and 100 µm film thickness) fibers were compared on the basis of their absorption capacities for the selected compounds, and PDMS 100 µm film thickness was selected. The influence of various parameters on PCBs extraction efficiency by HS-SPME was studied using GC-electron capture detector (ECD) compared with solid phase. The performance of proposed HS-SPME–GC methodology with respect to linearity, reproducibility and limit of detection (LOD) was evaluated by water spiked with target compounds. The linear range of most compounds was found to be between 0.1 and 100 µgL−1 and the limits of detection were between 15.2 and 63.8 ngL−1. The reproducibility of the method (n = 6), expressed as relative standard deviation (RSD), was between 4 and 10%. Finally, developed procedure was applied to determine selected PCBs in seawater samples.
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Stoichev, Teodor, Paulo de Morais, M. Clara P. Basto, and M. Teresa S. D. Vasconcelos. "Interferences of Surfactants During Determination of Chlorophenols by Acetylation Coupled to Headspace-Solid Phase Microextraction-Gas Chromatography with an Electron Capture Detector." Journal of AOAC INTERNATIONAL 98, no. 2 (March 1, 2015): 524–28. http://dx.doi.org/10.5740/jaoacint.14-126.
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Abstract The micellar extraction (ME) of chlorophenols (CPs) from solid samples is rapid and avoids the use of organic solvents. The cationic surfactant cetyltrimethylammonium bromide (CTAB) is a powerful agent for ME of CPs. However, CTAB will be an important interference when the extracts are subsequently analyzed by direct solid phase microextraction (SPME) without a previous derivatization step. Therefore, CTAB is usually replaced by the nonionic surfactant polyoxyethylene-10-lauryl ether (POLE), which causes less interference but is less efficient in extracting CPs. In order to assess to what extent the derivatization of CPs with headspace (HS) sampling would be able to reduce surfactant interferences, CPs were measured in the presence of CTAB or POLE using acetylation and HS-SPME coupled to GC with an electron capture detector. Experiments were carried out both in water and in a 0.1 g/mL solution of NaCl (salting out agent). Acetylation and HS-SPME strongly decreased the interference of CTAB for CP determination. Therefore, the application of CTAB followed by SPME determination for an efficient ME of CPs from solid samples should be reconsidered since using CTAB with HS-SPME after acetylation proved to be a potential tool for CP determination in those matrixes after method optimization.
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Torabbeigi, Marzieh, Parviz Abroomand Azar, Anousheh Sharifan, and Zahra Aghaei Meibodi. "Antibacterial Activity and Comparison of the Volatile Constituents Obtained by Several Extraction Methods from the Flowers, Stems and Leaves of Astrodaucus orientalis." Natural Product Communications 7, no. 2 (February 2012): 1934578X1200700. http://dx.doi.org/10.1177/1934578x1200700236.
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The oils of the flowers, stems and leaves of Astrodaucus orientalis L. were separately extracted using hydrodistillation (HD), head-space solid-phase microextraction (HS-SPME) and microwave assisted head-space solid-phase microextraction (MA-HS-SPME). The volatile constituents were analyzed by GC and GC/MS. Temperature and time of extraction, microwave power and exposure time of extraction were optimized. Polydimethylsiloxane (PDMS) fiber was used as the solid phase for SPME methods. The main constituents of the flower, stem and leaf oils isolated by HD, HS-SPME and MA-HS-SPME are as follows, respectively: β-pinene (20.5%, 13.9% and 30.4%), α-thujene (8.7%, 16.2% and 10.9%) and α-pinene (7.6%, 14.3% and 10.9%) for the flowers, sabinene (11.8%, 32.3% and 11.8%), α-pinene (8.7%, 28.8% and 6.1%) and p-mycrene (2.5%, 12% and 8.5%) for the stem, and α-pinene (9.4%, 37.1% and 22.5%), sabinene (13.5%, 26.3% and 23.5%), β-pinene (6.3%, 9.8% and 10%) and p-mycrene (3.2%, 2.5% and 15.6%) for the leaf. The minimum inhibitory concentrations (MIC) were determined for all essential oils obtained by HD against both Gram-positive ( Bacillus subtilis) and Gram-negative ( Escherichia coli) bacteria using the agar dilution method. These oils showed the good activities against the both bacteria (0.5 – 1.5 mg/mL).
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Ren, Yong Lin, Benjamin Padovan, and James M. Desmarchelier. "Evaluation of Headspace Solid-Phase Microextraction for Analysis of Phosphine Residues in Wheat." Journal of AOAC INTERNATIONAL 95, no. 2 (March 1, 2012): 549–53. http://dx.doi.org/10.5740/jaoacint.10-514.
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Abstract In headspace (HS) analysis, a fumigant is released from a commodity into a gas-tight container by grinding, heating, or microwaves. A new technique uses HS-solid-phase microextraction (SPME) for additional preconcentration of fumigant. HS-SPME was tested for detection of phosphine (PH3), chosen for examination because of its wide use on stored commodities. PH3 was applied to 50 g wheat in separate 250 mL sealed flasks, which were equipped either with a septum for conventional HS analysis or with one of four HS-SPME fibers [100 μm polydimethylsiloxane (PDMS), 85 μm carboxen (CAR)/PDMS, 75 μm CAR/PDMS, and 65 μm PDMS/divinylbenzene (DVB)]. The wheat was heated at 45°C for 20 min. In conventional HS analysis, a gaseous aliquot (80 μL) was taken from the HS and injected into the GC instrument. In the HS-SPME procedure, the fiber was removed from the HS and exposed in the heated injection port of the GC instrument. In all cases, PH3 was determined under the same chromatographic conditions with a GC pulsed flame photometric detector. In a comparison of the efficacy of the fibers, the bipolar fibers (CAR/PDMS and PDMS/DVB) contained more PH3 than the aliquot in the conventional HS analysis; larger size bipolar fibers extracted PH3 more efficiently than smaller fibers (e.g., 85 > 75 > 65 μm). The nonpolar fiber (PDMS) contained no PH3. Four fortification levels of PH3 on wheat were tested: 0.01, 0.05, 0.1, and 0.3 μg/g. The response of each bipolar fiber increased with the fortification levels, but the conventional HS analysis detected no fumigant at the lowest fortification level of 0.01 mg/g. Under the conditions of the validation study, the LOD was in the range of 0.005–0.01 ng PH3/g wheat.
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Braga, Gilberto Costa, Adna Prado, Jair Sebastião da Silva Pinto, and Severino Matias de Alencar. "Volatile profile of yellow passion fruit juice by static headspace and solid phase microextraction techniques." Ciência Rural 45, no. 2 (February 2015): 356–63. http://dx.doi.org/10.1590/0103-8478cr20130777.
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The profile of volatile compounds of yellow passion fruit juice was analyzed by solid phase microextraction headspace (HS-SPME) and optimized static headspace (S-HS) extraction techniques. Time, temperature, NaCl concentration and sample volume headspace equilibrium parameters was adjusted to the S-HS technique. The gaseous phase in the headspace of samples was collected and injected into a gas chromatograph coupled to a mass spectrometer. In the HS-SPME technique was identified 44 volatile compounds from the yellow passion fruit juice, but with S-HS only 30 compounds were identified. Volatile esters were majority in both techniques, being identified ethyl butanoate, ethyl hexanoate, (3z)-3-hexenyl acetate, hexyl acetate, hexyl butanoate and hexyl hexanoate. Aldehydes and ketones were not identified in S-HS, but were in HS-SPME. β-Pinene, p-cymene, limonene, (Z)-β-ocimene, (E)-β-ocimene, γ-terpinene, α-terpinolene and (E) -4,8-dimethyl-1, 3,7 - nonatriene terpenes were identified in both techniques. This study showed that the S-HS optimized extraction technique was effective to recovery high concentrations of the major volatile characteristics compounds in the passion fruit, such as ethyl butanoate and ethyl hexanoate, which can be advantageous due to the simplicity of the method.
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Liu, Yong Li, and Xian Yin Ping. "Analysis of Polychlorinated Biphenyls in Biological Samples by Headspace Solid Phase Microextraction Coupled with Gas Chromatography." Advanced Materials Research 1092-1093 (March 2015): 770–73. http://dx.doi.org/10.4028/www.scientific.net/amr.1092-1093.770.
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Based on headspace solid phase microextraction (HS-SPME) procedure coupled with gas chromatography, a method for determination of polychlorinated biphenyls (PCBs) in biological samples was developed. The optimization of factors influencing the performances of SPME was studied in detail. To perform the HS-SPME polydimethylsiloxane (PDMS), polydimethylsiloxane-divinyl benzene (PDMS-DVB) and polyacrylate (PA) fibers were compared on the basis of their absorption capacities for the selected compounds, and PDMS-DVB fiber was selected. The influence of various parameters on PCBs extraction efficiency by HS-SPME was studied using GC-electron capture detector (ECD). The linear range of most compounds was found to be between 1 and 100 μgL−1 and the limits of detection were between 20.1 and 42.3 ngL−1. The reproducibility of the method (n = 6), expressed as relative standard deviation (RSD), was between 4.63 and 9.71%. Finally, the optimization of method was applied to determine selected PCBs in biological samples.
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Xie, Zhisheng, Qundi Liu, Zhikun Liang, Mingqian Zhao, Xiaoxue Yu, Depo Yang, and Xinjun Xu. "The GC/MS Analysis of Volatile Components Extracted by Different Methods fromExocarpium Citri Grandis." Journal of Analytical Methods in Chemistry 2013 (2013): 1–8. http://dx.doi.org/10.1155/2013/918406.
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Volatile components fromExocarpium Citri Grandis(ECG) were, respectively, extracted by three methods, that is, steam distillation (SD), headspace solid-phase microextraction (HS-SPME), and solvent extraction (SE). A total of 81 compounds were identified by gas chromatography-mass spectrometry including 77 (SD), 56 (HS-SPME), and 48 (SE) compounds, respectively. Despite of the extraction method, terpenes (39.98~57.81%) were the main volatile components of ECG, mainly germacrene-D, limonene, 2,6,8,10,14-hexadecapentaene, 2,6,11,15-tetramethyl-, (E,E,E)-, andtrans-caryophyllene. Comparison was made among the three methods in terms of extraction profile and property. SD relatively gave an entire profile of volatile in ECG by long-time extraction; SE enabled the analysis of low volatility and high molecular weight compounds but lost some volatiles components; HS-SPME generated satisfactory extraction efficiency and gave similar results to those of SD at analytical level when consuming less sample amount, shorter extraction time, and simpler procedure. Although SD and SE were treated as traditionally preparative extractive techniques for volatiles in both small batches and large scale, HS-SPME coupled with GC/MS could be useful and appropriative for the rapid extraction and qualitative analysis of volatile components from medicinal plants at analytical level.
Dissertations / Theses on the topic "HS-SPME"
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Pavarini, Daniel Petinatti. "Investigação multidisciplinar da biossíntese de sesquiterpenos bioativos de Lychnophora ericoides (Vernonieae: Asteraceae)." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/60/60138/tde-17042015-104826/.
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Lychnophora (Vernonieae: Asteraceae) é um gênero micro-endêmico dos \"campus rupestris\" do bioma Cerrado. Os extratos foliares de Lychnophora ericoides (\"Arnica-da-serra\") são usados na terapêutica popular principalmente como analgésico. Seus óleos essenciais são quimicamente ricos em sesquiterpenos. Tais compostos, principalmente os de esqueletos bisabolano e cadinano são produtos biossintéticos do precursor cátion nerolidila. Óleos essenciais de folhas de L. ericoides são bioativos frente a invertebrados do Táxon Acari. Um de seus componentes majoritários, o orto-acetoxi bisabolol, é antinociceptivo em ensaios in vitro. Terpenos são valorizados pela indústria de química fina, haja vista sucessos como Taxol® e Acheflan®. Nossos objetivos em Fitoquímica e Ciências Farmacêuticas se alinham a esse interesse. As terpeno-sintases (TerpS) envolvidas na biossínteses dos compostos são ainda alvo de pesquisas com em Bioquímica. Sua identificação é frequentemente conclusiva em diversos aspectos. Como exemplo, citamos a compreensão dos mecanismos da variabilidade metabólica temporal em espécies nativas e selvagens e os avanços na bioengenharia de Produtos Naturais (PN). Frente a este cenário de fronteira este manuscrito traz um resumo da investigação que objetivou determinar se há diversas isoformas de TerpS operando na produção temporalmente variável de sesquiterpenos bioativos em tecidos foliares de Lychnophora ericoides ou se não as há. Acessamos diferentes amostras selvagens de L. ericoides in situ. Nossos esforços em responder a questão supracitada foram divididos em tarefas, a seguir: (1) Determinação da fração rica em sesquiterpenos inspirada na \"Química Analítica Verde\"; (2) MALDI imaging das proteínas das folhas; (3) Estratégia \"omics\" combinada na identificação e clonagem das TerpS. Visitamos campos de ocorrência (CampO) georreferenciados bem como desconhecidos. O desenvolvimento de método de quantificação por Headspace-SPME permitiu uma comparação rápida e livre de solventes de amostras vegetais mínimas (10 mg). A separação e identificação foi conduzida por Gas Chromatography-Mass Spectrometry (GC-MS). As amostras de Diamantina, CampO mais Boreal de todos, apresentam a maior quantidade de derivados bisabolano. A hidrodestilação do material vegetal excedente ao HS-SPME forneceu óleos essenciais para o isolamento de moléculas. Dados espectrais diversos fundamentam a descrição de um derivado cadinano, o 11-dehidro cadinol, entre outros. O MALDI imaging determinou como exequível a geração de imagens moleculares em folhas de L. ericoides. Foram geradas imagens subepidermais dos íons com m/z que se assemelham a cadinano e bisabolano synthases (CadS and BS). A limitação do emprego da técnica é a determinação previa da massa nominal da proteína nativa. Polyacrylamide Gel Electrophoresis (1D-PAGE) gerou mapas de proteínas separadas por tamanho (A, B, C, e D) (30KDa> m/z <80KDa). A digestão com tripsina das bandas geraram peptídeos para análise em MS. Íons resultantes alimentaram o algorítimo MASCOT. Uma isoforma de germacrano-sintase foi identificada. Prospecção de genes codificadores com o cDNA (Ubiquitina +) determinou uma BS, de comprimento 1600pb, amplificada com primers de design para genes de Helianthus spp. A BS de L. ericoides foi clonada. Concluindo, destacamos dois pontos. (1) O controle enzimático na produção dos sesquiterpenos poderá enfim ser averiguada a nível do transcriptoma. (2) A busca pela produção biotecnológica de PN sofreu um pequeno incremento. Esperamos ter contribuído humildemente na produção sustentável de PN e por conseguinte na preservação da biodiversidade.Lychnophora (Vernonieae: Asteraceae) is micro endemic to \"campus rupestris\" from Brazilian \"Cerrado\". Leaves extracts of Lychnophora ericoides (\"Arnica-da-serra\") are used as folk medicine and mainly as wound healer. Its essential oils were chemically profiled as sesquiterpene-rich. Such sesquiterpenes, both bisabolene-like and cadinane-like carbon skeletons, are derivatives of the nerolidyl cation. L. ericoides leaves essential oils are bioactive against invertebrate Acari. An anti-hypernociceptive ability of its component orto-acetoxy bisabolol was also displayed in vitro. Terpenes are valuable in fine chemistry industry, e.g. Taxol® and Acheflan®. Our phytochemical and pharmaceutical goals are aligned to such an interest. Terpene synthases (TerpS) behind their biosynthesis are target of researches in plant sciences and biochemistry. Identification of TerpS often led to conclusions with diverse impacts. Fundamental concepts on time-dependent shifts of terpene productions in wild type species and advances towards plant metabolites bioengineering are examples. Facing such a frontier field we share here an abstract for the investigation aimed to determine whether there were many isoforms of sesquiterpene synthases operating at leaves tissues in Lychnophora ericoides shift-able production of bioactive sesquiterpenes or whether there were not. We have accessed different in situ samples of L. ericoides. Efforts to answer the above question were sectioned as follows: (1) \"Green-Analytical-Chemistry\" oriented profiling of sesquiterpene-rich fraction; (2) MALDI imaging of proteins in leaves; (3) Combined \"omics\" approaches towards identifying TerpS and gene cloning. We visited both known and novel L. ericoides sites of occurrence (SoO). The development of a quantitative Headspace-Solid Phase Micro Extraction (HS-SPME) method enabled a rapid and solvent-free comparison of minimized samples (10mg). Separation and identification were carried out using Gas Chromatography-Mass Spectrometry (GC-MS). Samples harvested in Diamantina, Northern Most SoO, accumulate the highest amount of bisabolene-like derivatives. Hydrodistillation of leftovers material from HS-SPME yield essential oils used to purify unknown compounds. Based on a diverse spectra collection we report a novel cadinane-like derivative, one 11dehydro Cadinol. MALDI imaging has been determined as suitable for imaging proteins in L. ericoides. In a prospective fashion we generate sub-epidermal images of ions within the m/z frame comprising reported isoforms of both cadinane and bisabolane synthases (CadS and BS). The limitation to its use is the awareness of molecular weight of targeted native proteins. Polyacrylamide Gel Electrophoresis (1D-PAGE) protein mapping determined broad bands of protein distribution in different mass ranges (A, B, C, and D) (30KDa> m/z <80KDa). Bands tryptic digestion, followed by sample clean up, generated peptide pools feasible for MS. The output ions data feed MASCOT algorithm. A germacrane synthase could have been identified. When prospecting encoding genes, viable cDNA (Ubiquitin +) was used. A BS, lengthened 1600bp, was amplified with BS primers designed for Helianthus spp. genes. BS presented in L. ericoides was successfully cloned. In conclusion we headline two topics. (1) Hypothetical enzymatic control of the sesquiterpenes production can now be further investigated at transcriptome level. (2) The seek of a platform that guarantee natural products production in a controlled system has been moved forward. Future production of valued compounds can slightly rely in our humble contribution to support biodiversity conservation.
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Pavarini, Daniel Petinatti. "Variabilidade temporal e intraespecífica dos constituintes voláteis das folhas de Lychnophora ericoides Mart." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/60/60138/tde-28032012-155624/.
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A literatura relata variações espaciais e rítmicas para diferentes classes de metabólitos secundários, entretanto os dados são consistentes apenas para espécies que ocorrem em áreas temperadas. Lychnophora ericoides Mart. tem sido muito empregada popularmente como antiinflamatório e analgésico. É relatado o uso de suas partes aéreas pela população que vive nas proximidades de seu habitat em tratamentos de lesões cutâneas. L. eriocides representa uma das várias espécies da família Asteraceae endêmicas ao cerrado que biossintetizam uma ampla gama de terpenoides. Embora pouco estudada, sabe-se que a fração volátil de suas partes aéreas apresenta constituição terpênica. O presente estudo tem como objetivo determinar a constituição química desta fração volátil por meio de técnicas brandas de pré-concentração dos analitos e avaliar a variabilidade química desta fração a nível intraespecífico e temporal. Dessa forma, as coletas foram realizadas durante um período de 15 meses e utilizou-se HSSPME e CG-EM para avaliar as amostras coletadas. Um método para pré-concentração dos compostos voláteis (COVs) foi desenvolvido a partir da otimização dos parâmetros para obtenção do equilíbrio termodinâmico em HS-SPME. A obtenção de cromatogramas, determinação de índices de retenção relativos e aquisição de espectros de massas com ionização por elétrons possibilitaram a identificação de 7 monoterpenos majoritários e 1 sesquiterpeno também majoritário. Foi detectada a presença de um sesquiterpeno em amostras analisadas por HS-SPME que não se faz presente, de forma majoritária, nos óleos essenciais. Foram também realizados processos de hidrodestilação para obtenção dos óleos essenciais. A partir dos óleos essenciais foi possível isolar 3 sesquiterpenos por meio de CCDP e, para duas dentre estas substâncias, foram adquiridos dados de IES-EM, IES-EM/EM e RMN uni e bidimensionais. Um sesquiterpeno inédito na literatura, o acetato de bisabolila, teve sua estrutura elucidada por meio dos espectros adquiridos a partir de material isolado. Este sesquiterpeno, que está presente em preparados hidroalcoólicos utilizados na medicina popular, foi submetido a ensaios para avaliação do potencial anti-nociceptivo in vitro utilizando-se macrófagos peritoneais de ratos Wistar. Os resultados sugerem um efeito analgésico, devido à redução dos mediadores IL-1X e TNF-Y, os quais estão envolvidos no processo da dor inflamatória. É possível observar uma uniformidade intraespecífica nos níveis de COVs e uma tendência de comportamento a nível intraplanta e a nível circadiano de apresentar percentuais mais elevados de sesquiterpenos em épocas chuvosas e quentes (verão) e, analogamente, menos elevados em períodos de menor temperatura ambiente (durante a noite). Nas folhas mais jovens há uma têndencia destes valores relativos serem mais elevadosLiterature does report spatial and time-scale shifting on several secondary metabolites, despite such data are relevant just for those species which occurs within a temperate clime region. Lychnophora ericoides Mart. has been widely used as a folk medicine against pain and inflammation process. Off the region where is located L. ericoidess habitat there is an evident and extensive use of its aerial parts by the people which live there in order to treat several types of skin wound. In Brazilian Cerrado, tropical savanna, there a large numbers of endemic Asteraceae species, including L. ericoides, which are capable of biosynthesizing a wide variety of terpenoids. Considering the poor number of studies carried out concerning the L. ericoides volatile fraction it can be said that this fraction is quite formed by different classes of terpenes. This work aims to find the chemical composition of L. ericoides volatile fraction by using soft pre concentration techniques of compounds and investigate the chemical variability at time-scale and intraspecific levels. Thus, harvests were done throughout a 15 months period and HS-SPME & GC-MS were used to analyze the samples. A pre concentration method was developed by reaching optimum values for parameters involving the ideal thermodynamic equilibrium in HSSPME. The chromatograms acquisition, relative retention index calculations and electron ionization mass spectra acquisition, combined, made possible the identification of 7 monoterpenoids and 1 sesquiterpenoid. A particular sesquiterpene could have been identified only by using HS-SPME pre concentration and not by essential oils analysis. Using prep-TLC of the essential oils, 3 sesquiterpenes were isolated. The ESI-MS, ESI-MS/MS as well as 1D and 2D NMR spectra of two of these three isolated terpenes were acquired. One new sesquiterpene, bisabolyl acetate, had his structure elucidated at the end of this process. This sesquiterpene is displayed in hydro alcoholic extracts used in folk medicine. Bioassays for in vitro antinociceptive investigations using peritoneal macrophages isolated of Wistar rats were done using the bisabolyl acetate. Results on this investigation may suggest that a pain relief effect could be described for this compound, every since it was possible to notice a reducing on IL-1X and TNF-Y levels. These two cytokines are involved in inflammatory pain. A regular pattern on volatile levels within the samples couldve been noticed, and it is what could be called an intraspecific uniformity. A trend on both intraplant and circadian investigations couldve been observed and what tends to happen is a rising on sesquiterpenes level by the period of year which the rainy and warm summer is governing the weather. In an opposite way these levels tend to diminish by the period in which the lower temperatures are registered (throughout the night time). Among the younger leaves there is also a trend on higher sesquiterpenes levels to occur.
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Favreto, Wagner Alex Jann. "Fibra de vidro recoberta com ZnO como suporte para análise de trihalometanos por HS-SPME-CG." Universidade Estadual do Oeste do Parana, 2008. http://tede.unioeste.br:8080/tede/handle/tede/1884.
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Previous issue date: 2008-11-28In the present work we describe the methodology to obtain and modify the surface of glass fibers composed by Li2O - ZrO2 - BaO - SiO2 with zinc oxide. The glass fibers were obtained by classical fusion followed by the stretch of the vitreous fused mass, where the diameter of the fibers was controlled by the stretching velocity. They were recovered with ZnO by dip-coating and sol-gel processing of deposition, using both inorganic and organic polymeric gel methods, where the zinc acetate dihydrate was the zinc oxide precursor. The superficial morphology of the fiber was verified by scanning electron microscopy (SEM) and the zinc oxide layer was characterized by mapping of Kα and Lα lines of the zinc by EDX analyses. The results of the SEM characterization pointed out the deposition of ZnO by inorganic polymeric gel method results in a thick layer of the oxide without apparent porosity, while by the organic polymeric gel method results a dip homogeneous and porous layer of ZnO over the glass fiber surface. The glass fibers recovered with ZnO by organic polymeric gel were used to develop an analytical methodology to simultaneous determination of trihalomethanes (THM´s) in drinking water using headspace-SPME-Gas Chromatography. The study was based on the selectivity, linearity, accuracy, precision and recovery of the analytical method using the glass fiber/ZnO. The effect of the salt addition, extraction temperature and extraction, desorption and incubated time on the analytical response were evaluated too. Good linear dynamic range was observed from the method quantification limits with correlation coefficients better than 0.9900 for all compounds. The method was accurate with recoveries ranging from 95,00 to 105,00%. and the range of linearity observed was 30 ng/mL to 500 ng/mL to trichloromethane, 20 ng/mL to 250 ng/mL to dichlorobromomethane and dibromochloromethane and 10 ng/mL to 100 ng/mL to tribromethane. The method is also robust and has great potential to be used in a trihalomethane determination.
No presente trabalho encontram-se descritas a metodologia para obtenção, e para a modificação da superfície de fibras de vidro de composição Li2O - ZrO2 - BaO - SiO2 com óxido de zinco. As fibras de vidro foram obtidas pelo método de fusão clássico, seguido do estiramento da massa vítrea fundida, controlando-se o diâmetro através da velocidade de estiramento. Estas foram recobertas com ZnO, utilizando-se da técnica sol-gel em dip-coating controlado, usando-se os métodos de deposição do gel polimérico inorgânico e do gel polimérico orgânico, onde o acetato de zinco di-hidratado foi empregado como reagente precursor do óxido de zinco. Utilizou-se a técnica de Microscopia Eletrônica de Varredura (MEV) para avaliar a morfologia das fibras sem recobrimento e das fibras recobertas. O recobrimento com óxido de zinco sobre a superfície das fibras, foi mapeado através das linhas Kα e Lα do zinco, por Microssonda de Energia Dispersiva (EDS), sendo observado uma camada regular de ZnO sobre a superfície do suporte. Através dos resultados obtidos por MEV, verificou-se que pela técnica de deposição do gel polimérico inorgânico as fibras apresentam recobrimento bastante espesso, mas sem porosidade aparente. Quanto à técnica de deposição do gel polimérico orgânico, obtem-se fibras com um recobrimento mais homogêneo, espesso e poroso. Desta forma utilizaram-se as fibras recobertas pelo método do gel polimérico orgânico, para o desenvolvimento de metodologia analítica para determinações cromatográficas de trihalometanos (THM s) em solução aquosa. Utilizou-se da técnica de extração em head-space (HS) por Microextração em Fase Sólida (SPME) (HS-SPME) conjugada a Cromatografia Gasosa (CG). O estudo foi baseado na seletividade, linearidades, exatidão, precisão e na recuperação do método analítico usando a fibra de vidro/ZnO. O efeito da adição de sal, temperatura e tempo de extração, tempo de dessorção e o tempo de incubação na resposta analítica. O bom alcance dinâmico linear, foi observado nos limites da quantificação do método com coeficientes de correlação maiores que 0,99 observados para todos os compostos. O método demonstrou-se exato e com a recuperações que variam de 95,00 a 105,00% com escala de linearidades observadas entre 30 ng/mL a 500 ng/mL para o triclorometano, 20 ng/mL a 250 ng/mL ao diclorobromometano e o dibromoclorometano e 10 ng/mL a 100 ng/mL para o tribromometano. O método apresentou-se robusto, e possui grande potencial para ser usado em determinações de trihalometanos.
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Hartmann, Peter J. "The Effect of Wine Matrix Ingredients on 3-Alkyl-2-methoxypyrazines Measurements by Headspace Solid-Phase Microextraction (HS-SPME)." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/31616.
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The effect of wine matrix ingredients and conditions on the headspace (HS) sampling of 3-alkyl-2-methoxypyrazines was investigated with solid-phase microextraction (SPME) and capillary gas chromatography, using a nitrogen phosphorus detector. Changes in the recovery of 3-ethyl-, isopropyl-, sec-butyl-, and isobutyl-2-methoxypyrazines from the static headspace of synthetic wine matrices spiked with 5mg/L of each analyte were investigated and reported as a function of SPME fiber type, extraction time, and temperature. The influence of pH, ethanol, phenolics, and ground oak was studied.
DVB/Carboxen?/PDMS SPME fibers at an extraction temperature of 50°C for 30 minutes with 30% (w/v) added sodium chloride resulted in the highest analyte recoveries. Although, PDMS (100 micron) SPME fibers at an extraction temperature of 35°C for 30 minutes with 30% (w/v) added sodium chloride resulted in the lower analyte recoveries, the fiber remained functional after 50 to 75 analyses after other coatings deteriorated. Changing the sample ethanol concentration from 0 to 20% (v/v) resulted in an exponential decrease in the recovered analytes. Below pH 2, there was extensive loss of the analytes in the headspace. No measurable impact on alkylmethoxypyrazine headspace concentrations was observed with exposures to selected phenolics and to ground oak.Master of Science
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Sousa, Paulo Herbesson Pereira de. "Ecologia química como um mediador na atratividade de fêmeas Centris analis (Hymenoptera, Apidae) para colonização de ninhos, criação e manejo." reponame:Repositório Institucional da UFC, 2017. http://www.repositorio.ufc.br/handle/riufc/23896.
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SOUSA, Paulo Herbesson Pereira de. Ecologia química como um mediador na atratividade de fêmeas Centris analis (Hymenoptera, Apidae) para colonização de ninhos, criação e manejo. 2017. 68 f. Dissertação (Mestrado em Zootecnia)– Universidade Federal do Ceará, Fortaleza, 2017.Submitted by Francisca Gomes (francisbeserra@yahoo.com.br) on 2017-06-27T18:09:08Z No. of bitstreams: 1 2017_dis_phpsousa.pdf: 2099417 bytes, checksum: 71080e1991836276fde90bfc11985473 (MD5)
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Raising and managing Centris analis bees is facilitated by the use of trap nests, however, there is few number of research regarding factors that may influence the process of attracting nest-founding females. The present study aimed to identify volatile organic compounds (VOCs) existing in nests of C. analis, by employing the solid-phase microextraction (SPME) in order to learn about those compounds and variations of their chemical composition. This study also intended to optimize an extraction method for VOCs in food samples of immature C. analis. We made use of three types of fiber: apolar PDMS (Polydimethylsiloxane), bipolar CAR/PDMS (Carboxen/Polydimethylsiloxane), and bipolar DVB/CAR/PDMS (Divinylbenzene/Carboxen/Polydimethylsiloxane). We identified 27 compounds bellowing to those chemical classes. Among the compounds; trans-nerolidol (67,15%), detected by the PDMS fiber; hexanal (12,72%) and 3-methyl-1-butanol acetate (10,95%), detected by CAR/PDMS fiber; were the most representative for this sample. CAR/PDMS fiber was more selective extracting 20 compounds, DVB/CAR/PDMS and PDMS, 17 and 10 respectively. CAR/PDMS proved to be the most suitable for the extraction of VOCs in nests of Centris analis. When using CAR/PDMS fiber, we identified 40 VOCs belonging to nine chemical classes in food samples, oil and resin, used nest, and larvae. The major compounds cis-β-ocimene (35,7%), 2-Ethyl-1-hexanol (30,24%), p-xylene (24,59%) and 1-Octanol (20,63%), were detected in samples of oil, resin, used nest, and larvae, respectively. We noticed an existing variation in the diversity of volatile compounds according to larval and nest development, besides, certain compounds linger in the nest after emergence.
A criação e o manejo de abelhas Centris analis é facilitada pela utilização de ninhos armadilha, porém há poucas pesquisas sobre os fatores que possam influenciam no processo de atração de fêmeas fundadoras. O presente estudo teve como objetivo identificar os compostos orgânicos voláteis (COVs) presente no ninho de C. analis, utilizando a microextração em fase sólida (SPME) a fim de conhecer tais compostos e as variações na sua composição química. Este estudo buscou também, otimizar um método para extração dos COVs a partir de amostras do alimento de imaturos de C. analis. Utilizou-se três tipos de fibras: PDMS (Polidimetilsiloxano) apolar, CAR/PDMS (Carboxen/Polidimetilsiloxano)bipolar e DVB/CAR/PDMS (Divinilbezeno/Carboxen/Po lidimetilsiloxano) bipolar. Foram identificados 27 compostos pertencentes a cinco classes químicas. Entre os compostos, trans-nerolidol (67,15%) detectado pela fibra PDMS, hexanal (12,72%) e acetato de 3-metil-1-butanol (10,95 %) detectados pela fibra CAR/PDMS, foram os compostos de maior representatividade para esta amostra. A fibra CAR/PDMS foi mais seletiva, extraindo 20 compostos, DVB/CAR/PDMS e PDMS, 17 e 10 respectivamente. A fibra CAR/PDMS mostrou-se como mais indicada para extração de COVs em ninhos de Centris analis. Utilizando-se a fibra CAR/PDMS, foram identificados 40 COVs pertencentes a nove classes químicas em amostra de alimento, óleo e resina, ninho usado e lavas. Os compostos majoritários cis-β-ocimeno (35,7%), 2-Etil-1-hexanol (30,24%), p-xileno (24,59%) e 1-Octanol (20,63%), foram detectados em amostra de óleo e resina, ninho usado e lavas respectivamente. Verificamos que há uma variação na diversidade de composto voláteis segundo o desenvolvimento larval e do ninho e que determinados compostos permanecem no ninho após a emergência.
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Jakubčeková, Kristína. "Využití různých extrakčních technik pro analýzu výluhů z biouhlu." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2021. http://www.nusl.cz/ntk/nusl-449333.
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Biochar is a material whose properties, composition and impact on the environment are often discussed nowadays. The reason is its application as a soil conditioner. This leads to the need for qualitative as well as quantitative knowledge of its composition. This diploma thesis focuses on the qualitative analysis of biochar leachates processed by various extraction techniques. To approximate the real conditions, six aqueous mediums with different pH values is used, which a solid sample of biochar is exposed to. The prepared leachates are after that processed by extraction techniques, which are solid phase microextraction (SPME), single drop microextraction (HS-SDME), solid phase extraction (SPE) and liquid-liquid extraction (LLE). Analysis of the extracts was performed by gas chromatography-mass spectrometry (GC/MS). The measurements showed that the HS-SDME technique did not show a response. SPE was a rapid technique, but compared to other techniques, it acquired a smaller range of substances. Liquid-liquid extraction, a time-consuming technique, did not obtain as much analytes as SPME. By comparing these applied techniques, the SPME technique is the best choice. The most common determined analytes were those from the group of ketones and carboxylic acids and their derivatives.
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Rocha, Renier Felinto JuliÃo da. "Flavoromics de genÃtipos melhorados de mamÃo grupo solo: correlaÃÃo entre o perfil de compostos volÃteis e a qualidade sensorial." Universidade Federal do CearÃ, 2016. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=16815.
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CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel SuperiorAs variedades do mamÃo grupo Solo sÃo susceptÃveis a vÃrias doenÃas que restringem o mercado dos frutos in natura. A Embrapa vem desenvolvendo genÃtipos resistentes buscando caracterÃsticas agronÃmicas e sensoriais desejÃveis. Assim, objetivou-se caracterizar o perfil de volÃteis, compostos responsÃveis pelo aroma e sabor dos alimentos, e a qualidade sensorial de genÃtipos do grupo Solo, visando identificar novos cultivares com potencial para lanÃamento no mercado. Foram analisados quatro genÃtipos melhorados (CPMF L47-P8, CPMF L60-08, CPMF L47-P5 e CPMF H54-78) e uma variedade comercial (Sunrise). Para tanto, as condiÃÃes de extraÃÃo dos compostos pela tÃcnica HS-SPME foram otimizadas usando um Delineamento Composto Central Rotacional (DCCR), baseado em Metodologia de SuperfÃcie de Resposta, com duas variÃveis: tempo de equilÃbrio (0 a 30 min) e tempo de exposiÃÃo da fibra (20 a 60 min). As variÃveis dependentes foram nÃmero de picos, Ãrea total e intensidade do aroma. Os volÃteis foram extraÃdos com a fibra DVB/CAR/PDMS, separados e identificados por GC-MS. A anÃlise sensorial foi realizada com consumidores de mamÃo, por meio de testes afetivos de aceitaÃÃo global e aparÃncia, diagnÃstico de atributos (cor da polpa, aroma, sabor e textura) e intenÃÃo de compra. Os dados das anÃlises de compostos volÃteis foram submetidos à AnÃlise de Componentes Principais (ACP) e AnÃlise de Agrupamento HierÃrquico (clusters), e os da anÃlise sensorial foram submetidos à ANOVA e teste de Tukey. As duas matrizes de dados foram correlacionadas pela RegressÃo por MÃnimos Quadrados Parciais (PLS). As melhores condiÃÃes para a extraÃÃo dos volÃteis do mamÃo por HS-SPME foram 15 min de equilÃbrio e 60 min de exposiÃÃo da fibra. Nessas condiÃÃes foram identificados 70 compostos volÃteis, sendo os aldeÃdos os mais abundantes (em Ãrea), seguidos dos terpenos, Ãsteres, Ãlcoois e lactonas. Os genÃtipos CPMF L60-08 e CPMF L47-P5 apresentaram perfis de volÃteis semelhantes entre si e à variedade Sunrise, mas os genÃtipos CPMF H54-78 e CPMF L47-P8 apresentaram perfis de volÃteis Ãnicos. Quanto Ãs caracterÃsticas sensoriais, os genÃtipos CPMF L47-P8 e CPMF L47-P5 apresentaram-se semelhantes entre si, com textura mais firme e menor intensidade da cor da polpa, aroma e sabor que Sunrise, com menor aceitabilidade. O genÃtipo CPMF H54-78 apresentou boas caracterÃsticas sensoriais na degustaÃÃo, porÃm foi rejeitado quanto à aparÃncia externa. O genÃtipo CPMF L60-08 apresentou alta similaridade com a variedade comercial e mesma aceitabilidade, apesar da cor da polpa menos intensa. Os resultados da correlaÃÃo multivariada confirmam a superioridade do genÃtipo CPMF L60-08, o qual apresentou alta correlaÃÃo com a variedade Sunrise e com os atributos sensoriais. O presente trabalho recomenda o genÃtipo CPMF L60-08 como o promissor para substituir a variedade Sunrise (nÃo resistente a pragas e doenÃas), preservando o sabor e aroma caracterÃstico de mamÃo.
As variedades do mamÃo grupo Solo sÃo susceptÃveis a vÃrias doenÃas que restringem o mercado dos frutos in natura. A Embrapa vem desenvolvendo genÃtipos resistentes buscando caracterÃsticas agronÃmicas e sensoriais desejÃveis. Assim, objetivou -se caracterizar o perfil de volÃteis, compostos responsÃveis pelo aroma e sabor dos alimentos, e a qualidade sensorial de genÃtipos do grupo Solo, visando identificar novos cultivares com potencial para lanÃamento no mercado. Foram analisados quatro genÃtipos melhorados (CPMF L47-P8, CPMF L60-08, CPMF L47-P5 e CPMF H54- 78) e uma variedade comercial (Sunrise).Para tanto, as condiÃÃes de extraÃÃo dos compostos pela tÃcnica HS-SPME foram otimizadas usando um Delineamento Composto Central Rotacional (DCCR), baseado em Metodologia de SuperfÃcie de Resposta, com duas variÃveis: tempo de equilÃbrio (0 a 30 min) e tempo de exposiÃÃo da fibra (20 a 60 min). As variÃveis dependentes foram nÃmero de picos, Ãrea total e intensidade do aroma. Os volÃteis foram extraÃdos com a fibra DVB/CAR/PDMS, separados e identificados por GC-MS. A anÃlise sensorial foi realizada com consumidores de mamÃo, por meio de testes afetivos de aceitaÃÃo global e aparÃncia, diagnÃstico de atributos (cor da polpa, aroma, sabor e textura) e intenÃÃo de compra. Os dados das anÃlises de compostos volÃteis foram submetidos à AnÃlise de Componentes Principais (ACP) e AnÃlise de Agrupamento HierÃrquico (clusters), e os da anÃlise sensorial foram submetidos à ANOVA e teste de Tukey. As duas matrizes de dados foram correlacionadas pela RegressÃo por MÃnimos Quadrados Parciais (PLS). As melhores condiÃÃes para a extraÃÃo dos volÃteis do mamÃo por HS-SPME foram 15 min de equilÃbrio e 60 min de exposiÃÃo da fibra. Nessas condiÃÃes foram identificados 70 compostos volÃteis, sendo os aldeÃdos os mais abundantes (em Ãrea), seguidos dos terpenos, Ãsteres, Ãlcoois e lactonas. Os genÃtipos CPMF L60-08 e CPMF L47-P5 apresentaram perfis de volÃteis semelhantes entre si e à variedade Sunrise, mas os genÃtipos CPMF H54-78 e CPMF L47-P8 apresentaram perfis de volÃteis Ãnicos. Quanto Ãs caracterÃsticas sensoriais, os genÃtipos CPMF L47-P8 e CPMF L47-P5 apresentaram-se semelhantes entre si, com textura mais firme e menor intensidade da cor da polpa, aroma e sabor que Sunrise, com menor aceitabilidade. O genÃtipo CPMF H54-78 apresentou boas caracterÃsticas sensoriais na degustaÃÃo, porÃm foi rejeitado quanto à aparÃncia externa. O genÃtipo CPMF L60-08 apresentou alta similaridade com a variedade comercial e mesma aceitabilidade, apesar da cor da polpa menos intensa. Os resultados da correlaÃÃo multivariada confirmam a superioridade do genÃtipo CPMF L60-08, o qual apresentou alta correlaÃÃo com a variedade Sunrise e com os atributos sensoriais. O presente trabalho recomenda o genÃtipo CPMF L60-08 como o promissor para substituir a variedade Sunrise (nÃo resistente a pragas e doenÃas), preservando o sabor e aroma caracterÃstico de mamÃo.
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Rocha, Renier Felinto Julião da. "Flavoromics de genótipos melhorados de mamão grupo solo: correlação entre o perfil de compostos voláteis e a qualidade sensorial." reponame:Repositório Institucional da UFC, 2016. http://www.repositorio.ufc.br/handle/riufc/18150.
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ROCHA, Renier Felinto Julião da. Flavoromics de genótipos melhorados de mamão grupo solo: correlação entre o perfil de compostos voláteis e a qualidade sensorial. 2016. 79 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Tecnologia de Alimentos, Fortaleza-CE, 2016Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-05T14:44:47Z No. of bitstreams: 1 2016_dis_rfjrocha.pdf: 1677317 bytes, checksum: d35b0af0203d344c70ae8754c126512b (MD5)
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As variedades do mamão grupo Solo são susceptíveis a várias doenças que restringem o mercado dos frutos in natura. A Embrapa vem desenvolvendo genótipos resistentes buscando características agronômicas e sensoriais desejáveis. Assim, objetivou -se caracterizar o perfil de voláteis, compostos responsáveis pelo aroma e sabor dos alimentos, e a qualidade sensorial de genótipos do grupo Solo, visando identificar novos cultivares com potencial para lançamento no mercado. Foram analisados quatro genótipos melhorados (CPMF L47-P8, CPMF L60-08, CPMF L47-P5 e CPMF H54- 78) e uma variedade comercial (Sunrise).Para tanto, as condições de extração dos compostos pela técnica HS-SPME foram otimizadas usando um Delineamento Composto Central Rotacional (DCCR), baseado em Metodologia de Superfície de Resposta, com duas variáveis: tempo de equilíbrio (0 a 30 min) e tempo de exposição da fibra (20 a 60 min). As variáveis dependentes foram número de picos, área total e intensidade do aroma. Os voláteis foram extraídos com a fibra DVB/CAR/PDMS, separados e identificados por GC-MS. A análise sensorial foi realizada com consumidores de mamão, por meio de testes afetivos de aceitação global e aparência, diagnóstico de atributos (cor da polpa, aroma, sabor e textura) e intenção de compra. Os dados das análises de compostos voláteis foram submetidos à Análise de Componentes Principais (ACP) e Análise de Agrupamento Hierárquico (clusters), e os da análise sensorial foram submetidos à ANOVA e teste de Tukey. As duas matrizes de dados foram correlacionadas pela Regressão por Mínimos Quadrados Parciais (PLS). As melhores condições para a extração dos voláteis do mamão por HS-SPME foram 15 min de equilíbrio e 60 min de exposição da fibra. Nessas condições foram identificados 70 compostos voláteis, sendo os aldeídos os mais abundantes (em área), seguidos dos terpenos, ésteres, álcoois e lactonas. Os genótipos CPMF L60-08 e CPMF L47-P5 apresentaram perfis de voláteis semelhantes entre si e à variedade Sunrise, mas os genótipos CPMF H54-78 e CPMF L47-P8 apresentaram perfis de voláteis únicos. Quanto às características sensoriais, os genótipos CPMF L47-P8 e CPMF L47-P5 apresentaram-se semelhantes entre si, com textura mais firme e menor intensidade da cor da polpa, aroma e sabor que Sunrise, com menor aceitabilidade. O genótipo CPMF H54-78 apresentou boas características sensoriais na degustação, porém foi rejeitado quanto à aparência externa. O genótipo CPMF L60-08 apresentou alta similaridade com a variedade comercial e mesma aceitabilidade, apesar da cor da polpa menos intensa. Os resultados da correlação multivariada confirmam a superioridade do genótipo CPMF L60-08, o qual apresentou alta correlação com a variedade Sunrise e com os atributos sensoriais. O presente trabalho recomenda o genótipo CPMF L60-08 como o promissor para substituir a variedade Sunrise (não resistente a pragas e doenças), preservando o sabor e aroma característico de mamão.
As variedades do mamão grupo Solo são susceptíveis a várias doenças que restringem o mercado dos frutos in natura. A Embrapa vem desenvolvendo genótipos resistentes buscando características agronômicas e sensoriais desejáveis. Assim, objetivou-se caracterizar o perfil de voláteis, compostos responsáveis pelo aroma e sabor dos alimentos, e a qualidade sensorial de genótipos do grupo Solo, visando identificar novos cultivares com potencial para lançamento no mercado. Foram analisados quatro genótipos melhorados (CPMF L47-P8, CPMF L60-08, CPMF L47-P5 e CPMF H54-78) e uma variedade comercial (Sunrise). Para tanto, as condições de extração dos compostos pela técnica HS-SPME foram otimizadas usando um Delineamento Composto Central Rotacional (DCCR), baseado em Metodologia de Superfície de Resposta, com duas variáveis: tempo de equilíbrio (0 a 30 min) e tempo de exposição da fibra (20 a 60 min). As variáveis dependentes foram número de picos, área total e intensidade do aroma. Os voláteis foram extraídos com a fibra DVB/CAR/PDMS, separados e identificados por GC-MS. A análise sensorial foi realizada com consumidores de mamão, por meio de testes afetivos de aceitação global e aparência, diagnóstico de atributos (cor da polpa, aroma, sabor e textura) e intenção de compra. Os dados das análises de compostos voláteis foram submetidos à Análise de Componentes Principais (ACP) e Análise de Agrupamento Hierárquico (clusters), e os da análise sensorial foram submetidos à ANOVA e teste de Tukey. As duas matrizes de dados foram correlacionadas pela Regressão por Mínimos Quadrados Parciais (PLS). As melhores condições para a extração dos voláteis do mamão por HS-SPME foram 15 min de equilíbrio e 60 min de exposição da fibra. Nessas condições foram identificados 70 compostos voláteis, sendo os aldeídos os mais abundantes (em área), seguidos dos terpenos, ésteres, álcoois e lactonas. Os genótipos CPMF L60-08 e CPMF L47-P5 apresentaram perfis de voláteis semelhantes entre si e à variedade Sunrise, mas os genótipos CPMF H54-78 e CPMF L47-P8 apresentaram perfis de voláteis únicos. Quanto às características sensoriais, os genótipos CPMF L47-P8 e CPMF L47-P5 apresentaram-se semelhantes entre si, com textura mais firme e menor intensidade da cor da polpa, aroma e sabor que Sunrise, com menor aceitabilidade. O genótipo CPMF H54-78 apresentou boas características sensoriais na degustação, porém foi rejeitado quanto à aparência externa. O genótipo CPMF L60-08 apresentou alta similaridade com a variedade comercial e mesma aceitabilidade, apesar da cor da polpa menos intensa. Os resultados da correlação multivariada confirmam a superioridade do genótipo CPMF L60-08, o qual apresentou alta correlação com a variedade Sunrise e com os atributos sensoriais. O presente trabalho recomenda o genótipo CPMF L60-08 como o promissor para substituir a variedade Sunrise (não resistente a pragas e doenças), preservando o sabor e aroma característico de mamão.
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Elouma, Ndinga Arnold Murphy. "Inventaire et analyse chimique des exsudats des plantes d'utilisation courante au Congo-Brazzaville." Thesis, Paris 11, 2015. http://www.theses.fr/2015PA112023/document.
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Les exsudats des plantes sont des substances naturelles complexes. Ils sont utilisés par plusieurs populations d’Afrique et trouvent de nombreuses applications : en thérapeutique, en pharmacie galénique, en parfumerie, etc. Au Congo, une grande majorité de ces substances est encore mal connue. Ce travail de thèse a consisté à inventorier les plantes à exsudats du Congo et à mettre au point une méthodologie d’analyse physico-chimique permettant la caractérisation des exsudats d’arbres d’origine botanique certifiée.La méthodologie d’inventaire adoptée nous a permis de recenser 135 plantes à exsudats appartenant à 87 genres. Il en ressort de cette étude que les exsudats des plantes inventoriées ont multiples usages (glu, insectifuge, allume-feu, antidouleur, etc.).La stratégie mise en place pour leur caractérisation fait appel à plusieurs techniques analytiques (SPIR, SMIR, CPG-SM, GCxGC-MS) et de traitement d’échantillon (Hs-SPME, hydrodistillation, extraction au Soxhlet, silylation, méthylation, pyrolyse). Dans le cadre de ce travail deux exsudats ont été caractérisés. L’exsudat de D. edulis (G. Don) K.J. Lam qui est constitué de monoterpènes hydrocarbonés et de triterpènes, dont les majeurs sont : 3-épi-α et -β-amyrine. L’exsudat de G. demeusei (Harms) J. Léonard dont la fraction volatile est constituée essentiellement de sesquiterpènes et la fraction peu-volatile d’acides diterpéniques de type labdane (acide éperuique, cativique, copalique, ozique, etc.).Pour exploiter l’efficacité de séparation élevée de la GCxGC-MS, nous nous sommes confronté aux problèmes de la non-répétabilité des cartes chromatographiques obtenues en 2D. Nous avons alors mis en place une méthodologie permettant de vérifier l’épaisseur de film et l’homogénéité des dépôts de phases stationnaires afin de sélectionner des colonnes courtes identiques pour la GCxGC. Cependant, les résultats préliminaires ont montré que même avec des colonnes de deuxième dimension identiques, on pouvait avoir des différences au niveau de carte 2DPlant exudates are natural complex substances. They are used by several populations in Africa and have many applications: in therapeutics, in galenic pharmacy, in perfumery, etc. In Congo, a great majority of these substances are not yet well known. This thesis work aimed to make an inventory of plant exudates from Congo and to develop a methodology for performing physico-chemical analysis which may enable characterization of exudates from botanical certified trees.Through the methodology that we developed, 135 plant exudates belonging 87 genera were registered. It was observed in this study that these exudates are used for many purposes (glue, insect repellent, making fire, anti-pain, etc).The strategy implemented for characterizing the exudates included several analytical (SNIR, SMIR, GC-MS, GCxGC-MS) and sample processing (Hs-SPME, hydrodistillation, extraction using the Soxhlet, silylation, methylation pyrolyse) techniques. With regard to this work, two exudates were characterized. The exudates from D. edulis (G. Don) K.J. Lam which contained monoterpene hydrocarbons and triterpenes, with the major constituents being: 3-epi-α and -β-amyrine. The exudates from G. Demeusei (Harms) J. Léonard was found to have the sesquiterpenes as major constituents of the volatile fraction and the labdane-type diterpenes (eperuique acide, cativique acid, copalique acid, ozique acid, etc) as major constituents of the poor-volatile fraction.To explore the efficacy of elevated separation of the GCxGC-MS, we faced some problems related to the non-repeatability of chromatographic cards obtained in 2D. Therefore, we put in place a methodology which enables us to verify the film thickness and homogeneity of layers of stationary phases in order to select identical short columns for GCxGC. However, the preliminary results have shown that even using second identical dimension columns, we could observed differences in 2D cards
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Albonetti, Denise. "Studio del profilo aromatico della pesca. Stato dell'arte sulla caratterizzazione della composizione in volatili di pesche bianche e gialle." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/12790/.
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L’aroma, insieme a sapore e succosità, è uno dei componenti essenziali della qualità sensoriale della pesca, ed è da considerarsi una risposta integrata del sistema olfattivo a diversi composti volatili, quali alcoli, aldeidi, alcani, esteri, chetoni, lattoni e terpeni. La variabilità dei volatili nell’aroma della pesca dipende non soltanto da cultivar, gestione del frutteto, lavorazione, condizioni di conservazione, stadio di maturità e/o condizioni di maturazione, ma anche dalle procedure di estrazione e rilevamento attuate. In questo lavoro di tesi è stato condotto uno studio sullo stato dell’arte riguardante le tecniche analitiche maggiormente utilizzate per la determinazione dei volatili. In particolare, si è comparata la tecnica ritenuta più idonea all’estrazione di analiti volatili, ovvero la microestrazione in fase solida dello spazio di testa (HS-SPME), ad alcuni metodi tradizionali, tra i quali l’estrazione liquido-liquido (LLE), l’estrazione per distillazione in corrente di vapore (SDE) e la microestrazione liquido-liquido (LLME). Dai risultati riportati in bibliografia, la tecnica HS-SPME risulta essere quella con maggior percentuale di recupero di volatili, grazie alla rapidità di analisi e all’eliminazione dell’uso di solventi. Tuttavia, è emerso che alcune tecniche tradizionali sono più adatte per il campionamento di composti stabili, come svariati idrocarburi, non identificati con la tecnica HS-SPME. In conclusione, per ottenere risultati più completi ed attendibili, è consigliata la combinazione di più procedure di campionamento, in quanto complementari.
Book chapters on the topic "HS-SPME"
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Kaloudis, Triantafyllos, Theodoros M. Triantis, and Anastasia Hiskia. "Determination of Geosmin and 2-Methylisoborneol in Water by HS-SPME-GC/MS." In Handbook of Cyanobacterial Monitoring and Cyanotoxin Analysis, 469–74. Chichester, UK: John Wiley & Sons, Ltd, 2017. http://dx.doi.org/10.1002/9781119068761.ch59.
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Kluger, Bernhard, Susanne Zeilinger, Gerlinde Wiesenberger, Denise Schöfbeck, and Rainer Schuhmacher. "Detection and Identification of Fungal Microbial Volatile Organic Compounds by HS-SPME-GC–MS." In Laboratory Protocols in Fungal Biology, 455–65. New York, NY: Springer New York, 2012. http://dx.doi.org/10.1007/978-1-4614-2356-0_42.
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Loconto, Paul R. "Determination of Priority Pollutant Volatile Organic Compounds (VOCs) in Gasoline-Contaminated Groundwater Using Static Headspace (HS) and Solid-Phase Microextraction Headspace (SPME-HS) and Gas Chromatography." In Laboratory Experiments in Trace Environmental Quantitative Analysis, 99–106. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9781003260707-16.
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Sebastiani, Bartolomeo, Donatella Malfatti, Martino Giorgini, and Stefano Falcinelli. "Determination of Volatile Aroma Composition Profiles of Coco de Mèr (Lodoicea Maldivica) Fruit: Analytical Study by HS-SPME and GC/MS Techniques." In Computational Science and Its Applications – ICCSA 2017, 44–59. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-62398-6_4.
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Crespo, Julia, Valeria Romero, Margarita García, Teresa Arroyo, and Juan M. Cabellos. "Influence of Skin-Contact Treatment on Aroma Profile of Malvasia Aromatica Wines in D.O. “Vinos de Madrid”." In Grapes and Wine [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.99216.
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The effects of prefermentative cold skin-contact technique using Malvasia aromatica were studied as a first step to adapt to the climate change related effects in order to intensify the aroma potential of white wines of the D.O. “Vinos de Madrid” keeping the organoleptic characteristics of the region. Major volatile compounds were extracted by liquid–liquid extraction and quantified by GC-FID. Minor volatile compounds were determined by HS-SPME/GC–MS. Sensory analysis were also carried out to describe and quantify attributes of the wines. A total of 37 components were identified and quantified. Volatile components showed mixed behavior depending on the skin-contact time. Skin-contact for longer helps to enhance the floral character provided by some compounds contained in the skin, especially linalool and 2-phenyl etanol and were impact odorants of Malvasia aromatica wine based on odor activity values (OAVs).
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Torres-Moreno, Miriam, Amparo Tarrega, and Consol Blanch. "Characterization of Volatile Compounds in Dark Chocolates by HS-SPME and GC-MS." In Flavour Science, 283–87. Elsevier, 2014. http://dx.doi.org/10.1016/b978-0-12-398549-1.00054-4.
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LUPOTTO, ELISABETTA, BARBARA CAVAGNA, FEDERICA CORANA, CHIARA GIORGIO MELLERIO, CHIARA LANZANOVA, STEFANO CAVIGIOLO, and DIEGO GREPPI. "Quality Evaluation and High Throughput Analysis of Aromatic Italian Rice Varieties Through HS-SPME/GC-MS Analysis." In Consumer Driven Cereal Innovation, 78–82. Elsevier, 2008. http://dx.doi.org/10.1016/b978-1-891127-61-8.50022-4.
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García, Yesenia Mendoza, Eurico Eduardo Pinto de Lemos, Ana Luiza Coeli Cruz Ramos, Luisa Del Carmen Barrett Reina, Altamir Fernandes de Oliveira, Ana Cardoso Clemente Filha Ferreira de Paula, Angelita Cristine de Melo, Rodinei Augusti, Raquel Linhares Bello de Araújo, and Júlio Onésio Ferreira Melo. "EXTRAÇÃO E ANÁLISE DE COMPOSTOS ORGÂNICOS VOLÁTEIS POR SPME-HS E GC-MS – UM BREVE REFERENCIAL TEÓRICO." In Ciências Agrárias: o avanço da ciência no Brasil - Volume 1, 68–83. Editora Científica Digital, 2021. http://dx.doi.org/10.37885/210504640.
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Esposto, Sonia, Maurizio Servili, Roberto Selvaggini, I. Riccò, Agnese Taticchi, Stefania Urbani, and GianFrancesco Montedoro. "Discrimination of virgin olive oil defects—comparison of two evaluation methods: HS-SPME GC-MS and electronic nose." In Flavour Science - Recent Advances and Trends, 315–18. Elsevier, 2006. http://dx.doi.org/10.1016/s0167-4501(06)80075-0.
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"Headspace-Solid Phase Micro Extraction Coupled with Gas Chromatography-Mass Spectroscopy (HS-SPME-GCMS): An Efficient Tool for Qualitative and Quantitative Rice Aroma Analysis." In Science and Technology of Aroma, Flavor, and Fragrance in Rice, 159–96. Apple Academic Press, 2018. http://dx.doi.org/10.1201/b22468-17.
Full textConference papers on the topic "HS-SPME"
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Schmutzer, G., V. Avram, F. Covaciu, I. Feher, A. Magdas, L. David, and Z. Moldovan. "Study of flavour compounds from orange juices by HS-SPME and GC-MS." In PROCESSES IN ISOTOPES AND MOLECULES (PIM 2013). AIP, 2013. http://dx.doi.org/10.1063/1.4833701.
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Zhang, Lingling, Xiaofen Li, Xiangpei Wang, Yuqing Liang, Xianyou Yang, and Hongmei Wu. "Identification of Volatile Components of Fresh Indocalamus Latifolius Leaves by HS-SPME-GC-MS." In The Second International Conference on Materials Chemistry and Environmental Protection. SCITEPRESS - Science and Technology Publications, 2018. http://dx.doi.org/10.5220/0008184600100013.
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Paramita Bhattacharjee and Suranjan Panigrahi. "Quantitative Determination of VOCs Using HS-SPME: A Comprehensive Reviewed Application for Meat Safety." In ASABE/CSBE North Central Intersectional Meeting. St. Joseph, MI: American Society of Agricultural and Biological Engineers, 2007. http://dx.doi.org/10.13031/2013.24167.
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DELLO MONACO, D., C. DISTANTE, D. S. PRESICCE, P. SICILIANO, A. M. TAURINO, M. ZUPPA, A. CIMATO, and G. SANI. "ELECTRONIC NOSE, HS-SPME/GC/MS AND PANEL TEST CORRELATION FOR MONO –CULTIVAR EXTRA-VIRGIN OLIVE OILS." In Proceedings of the 9th Italian Conference. WORLD SCIENTIFIC, 2005. http://dx.doi.org/10.1142/9789812701770_0022.
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Li, Xingfang, Jie Xing, and Songyi Lin. "VARIETIES OF VOLATILE COMPOUNDS IN TREATED FTGSK BY PULSED ELECTRIC FIELDS ESTIMATED USING HS-SPME-GC-MS." In 2016 International Conference on Biotechnology and Medical Science. WORLD SCIENTIFIC, 2016. http://dx.doi.org/10.1142/9789813145870_0078.
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SANTANA, V. C. N., A. M. ELIAS, and G. L. V. COELHO. "DETERMINAÇÃO DOS COEFICIENTES DE ATIVIDADE NA DILUIÇÃO INFINITA DE COMPOSTOS ORGÂNICOS EM [BMIM] [MESO4] POR HS-SPME/GC-FID NAS TEMPERATURAS DE 298,15, 313,15, 333,15 E 353,15 K." In XI Congresso Brasileiro de Engenharia Química em Iniciação Científica. São Paulo: Editora Edgard Blücher, 2015. http://dx.doi.org/10.5151/chemeng-cobeqic2015-048-31972-263264.
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ELIAS, A. M., and G. L. V. COELHO. "DETERMINAÇÃO DOS COEFICIENTES DE ATIVIDADE NA DILUIÇÃO INFINITA DE COMPOSTOS ORGÂNICOS EM [BMIM] [MESO4] POR HS-SPME/GC-FID NAS TEMPERATURAS DE 298.15, 313.15, 333.15 E 353.15 K." In XX Congresso Brasileiro de Engenharia Química. São Paulo: Editora Edgard Blücher, 2015. http://dx.doi.org/10.5151/chemeng-cobeq2014-1800-17489-142772.
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