by Leung Yun-to, Ada. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 114-115). / Acknowledgment --- p.i / Abstract --- p.ii / Chapter 1. --- INTRODUCTION / Chapter 1.1 --- Review of gas-liquid chromatographic and other chromatographic techniques --- p.1 / Chapter 1.2 --- "Structures, actions and uses of the drugs under study" --- p.5 / Chapter 1.3 --- Research objectives --- p.10 / Chapter 2. --- INSTRUMENTATION AND THEORY / Chapter 2.1 --- Instrumentation for gas chromatography --- p.11 / Chapter 2.2 --- Basic principles in chromatography --- p.23 / Chapter 3. --- EXPERIMENTAL / Chapter 3.1 --- Instrumentation --- p.27 / Chapter 3.2 --- "The counter-check GC method for camphor, menthol and methyl salicylate" --- p.29 / Chapter 3.3 --- The counter-check HPLC method for thymol --- p.29 / Chapter 3.4 --- The counter-check HPLC method for phenol --- p.30 / Chapter 3.5 --- The counter-check HPLC method for benzoic acid --- p.31 / Chapter 3.6 --- The counter-check HPLC method for salicylic acid --- p.32 / Chapter 3.7 --- Reagents --- p.33 / Chapter 3.8 --- Sample preparation --- p.34 / Chapter 3.9 --- "Quantitative determination of benzoic acid, camphor, menthol, methyl salicylate, phenol, salicylic acid and thymol in various pharmaceutical preparations" --- p.35 / Chapter 4. --- RESULTS AND DISCUSSION / Chapter 4.1 --- Choice of column --- p.36 / Chapter 4.2 --- Optimization of chromatographic conditions --- p.44 / Chapter 4.3 --- Choice of solvent --- p.51 / Chapter 4.4 --- Calibration --- p.59 / Chapter 4.5 --- Reproducibility of the GC measurements --- p.95 / Chapter 4.6 --- Recovery test and precision studies --- p.96 / Chapter 4.7 --- Simultaneous determination of the drugs under study in various pharmaceutical preparations --- p.100 / Chapter 5. --- CONCLUSION --- p.113 / Chapter 6. --- REFERENCES --- p.114

No description available.

by Suk Che Ho. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 86-88). / Abstract also in Chinese. / Abstract --- p.i / Acknowledgments --- p.iii / Dedication --- p.iv / Abbreviations --- p.v / Table of Contents --- p.vi / Chapter Chapter 1: --- Introduction --- p.1 / Chapter 1.1 --- Overview of Chinese Medicinal Herbs containing essential oils --- p.1 / Chapter 1.1.1 --- Introduction of Chinese Medicinal Herbs --- p.1 / Chapter 1.1.2 --- Chinese Medicinal Herbs containing essential oils --- p.2 / Chapter 1.2 --- Recognition of Chinese Medicinal Herbs --- p.2 / Chapter 1.2.1 --- Traditional method in recognition of Chinese Medicinal Herbs (CMH) --- p.2 / Chapter 1.2.2 --- Instrumental Methods for the recognition of CMH --- p.4 / Chapter 1.2.3 --- The use of GC and GC/MS on CMH --- p.4 / Chapter 1.3 --- Motivation and objective of this research --- p.5 / Chapter 1.3.1 --- Motivation --- p.6 / Chapter 1.3.2 --- Objective of this research --- p.7 / Chapter 1.4 --- Outline of the methodology and arrangement of the thesis --- p.8 / Chapter Chapter 2: --- Experimental Setup --- p.11 / Chapter 2.1 --- Reagents and materials --- p.11 / Chapter 2.1.1 --- Reagents and glassware --- p.11 / Chapter 2.1.2 --- Materials --- p.11 / Chapter 2.2 --- Sample pretreatment --- p.14 / Chapter 2.3 --- Extraction of essential oils from the herbal samples --- p.14 / Chapter 2.3.1 --- Traditional extraction methods for essential oils --- p.14 / Chapter 2.3.2 --- Extraction by hydrodistillation using Dean and Stark-type trap --- p.15 / Chapter 2.4 --- Results --- p.17 / Chapter 2.4.1 --- Comparison with literature data --- p.17 / Chapter 2.4.2 --- Reproducibility of the extraction --- p.17 / Chapter 2.4.3 --- Recovery test --- p.26 / Chapter 2.5 --- Discussion --- p.27 / Chapter Chapter3: --- Instrumental Analysis of the Essential Oils --- p.29 / Chapter 3.1 --- GC analysis --- p.29 / Chapter 3.1.1 --- Instrumentation --- p.29 / Chapter 3.1.2 --- Instrumental settings --- p.31 / Chapter 3.1.3 --- The use of GC in the analysis of essential oils --- p.31 / Chapter 3.1.3.1 --- Qualitative data --- p.31 / Chapter 3.1.3.2 --- Quantitative data --- p.33 / Chapter 3.1.3.3 --- Dilution strategy --- p.33 / Chapter 3.1.4 --- Results --- p.36 / Chapter 3.1.4.1 --- Precision test --- p.36 / Chapter 3.1.4.2 --- Linearity --- p.39 / Chapter 3.2 --- GC/MS analysis --- p.41 / Chapter 3.2.1 --- Instrumentation --- p.41 / Chapter 3.2.2 --- Instrumental settings --- p.42 / Chapter 3.2.3 --- The use of GC/MS in the analysis of essential oils --- p.43 / Chapter 3.2.3.1 --- Identification by GC/MS --- p.43 / Chapter 3.2.3.2 --- Abundance information --- p.43 / Chapter 3.2.4 --- Results --- p.44 / Chapter 3.2.4.1 --- Precision test --- p.44 / Chapter 3.2.4.2 --- Linearity --- p.46 / Chapter 3.2.4.3 --- Detection limit --- p.48 / Chapter 3.2.4.4 --- Chromatographic patterns of herbal samples obtained by GC/MS --- p.49 / Chapter 3.3 --- Discussion --- p.49 / Chapter Chapter 4: --- Development of a system for recognition --- p.52 / Chapter 4.1 --- Introduction --- p.52 / Chapter 4.2 --- Analysis of chromatographic patterns --- p.53 / Chapter 4.2.1 --- Extraction of “effective´ح peaks --- p.54 / Chapter 4.2.2 --- Extraction of “characteristic´ح peaks --- p.56 / Chapter 4.3 --- Library section --- p.60 / Chapter 4.3.1 --- Calculation of relative retention indices --- p.60 / Chapter 4.3.2 --- Normalization factors --- p.61 / Chapter 4.4 --- Matching section --- p.62 / Chapter 4.4.1 --- Overview of the matching method --- p.62 / Chapter 4.4.2 --- Input --- p.63 / Chapter 4.4.3 --- Matching strategy --- p.64 / Chapter 4.4.4 --- Matching algorithms --- p.64 / Chapter 4.4.4.1 --- "Matching with “characteristic"" peaks" --- p.64 / Chapter 4.4.4.2 --- Matching with “effective´ح peaks --- p.65 / Chapter 4.4.5 --- Calculation of similarity scores --- p.66 / Chapter 4.4.6 --- Output --- p.69 / Chapter Chapter 5: --- Performance of the proposed recognition system --- p.70 / Chapter 5.1 --- Recognition performance of the database --- p.70 / Chapter 5.1.1 --- Definition of similarity --- p.70 / Chapter 5.1.2 --- Performance test of the recognition method --- p.70 / Chapter 5.1.2.1 --- Candidates in the library file --- p.70 / Chapter 5.1.2.2 --- Unknown not found in the library file --- p.75 / Chapter 5.1.3 --- Information drawn from the scores --- p.77 / Chapter 5.1.3.1 --- Recognition of the unknown sample in terms of similarity --- p.77 / Chapter 5.1.3.2 --- Relationship between the herbal drugs --- p.79 / Chapter 5.2 --- Applicability of the proposed methodology --- p.80 / Chapter 5.3 --- Limitation of the proposed methodology --- p.81 / Chapter 5.4 --- Future prospect --- p.81 / Chapter Chapter 6: --- Conclusion --- p.83 / References --- p.86 / Appendices / Chapter A. --- Linearity of calibration graphs using GC --- p.A1 / Chapter B. --- Linearity of calibration graphs using GC/MS --- p.A3 / Chapter C. --- GC/MS chromatograms of the herbal samples --- p.A5 / Chapter D. --- "Relative retention times of “effective"" and ""characteristic"" peaks" --- p.A28

Diss. (sammanfattning) Linköping : Univ., 2004. / Härtill 6 uppsatser.

Orientadores: Vera Lucia Garcia Rehder, Marta Cristina Teixeira Duarte / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-06T20:58:10Z (GMT). No. of bitstreams: 1 Taminato_RodrigoLuis_M.pdf: 889161 bytes, checksum: 74c08f7f56d17f89884a6856839f1ba1 (MD5) Previous issue date: 2006 / Resumo: De uso freqüente na medicina popular, o gênero Allium inclui mais de 600 espécies encontradas em diversas regiões do mundo como Europa, América do Norte, África e Ásia. A maioria das espécies é comestível e possui aroma e odor característicos, sendo também utilizadas como hipocolesterolêmico, antigripal e antimicrobiano. Alguns estudos de determinação das propriedades de Allium spp. como antifúngico e de identificação de seus compostos voláteis foram conduzidos. A maior parte de seus constituintes são compostos sulfurados, embora a composição química seja variável entre os diferentes estudos. Dentre as espécies de Allium spp., o A. tuberosum Rottl. ex Spreng (Liliaceae) pertence a mesma família do alho, cebola e alho-poró, é conhecido também como "Chinese chive", sendo um importante ingrediente na culinária asiática, também utilizado como erva medicinal para muitas disfunções e doenças. Na China é popularmente chamado de "Jiucai" e no Japão de "Nirá". Os óleos essenciais das folhas e bulbos deA. tuberosum obtidos por hidrodestilação em sistema do tipo Clevenger. As fases aquosas ou hidrolatos foram extraídas com diclorometano, obtendo-se o OB (óleo essencial dos bulbos) - 810 mg (0,12%) e o OF (óleo essencial das folhas) -750 mg (0,15%). O extrato dic1orometânico obtido dos bulbos - EB, obtido em sistema Ultra-Turrax, apresentou rendimento 3,28% (497 mg).O OB foi fracionado em coluna seca, utilizando como eluente dic1orometano. Foram obtidas, 8 frações (FI a F8), analisadas por CCD. As frações 3, 4 e 5 foram agrupadas resultando nas frações: FI - 138,6mg (33%), F2 - 15,3mg (3,7%), F3 - 13,6mg (3,3 %), F4 - 51,9 (12,6%), F5 - 34,lmg (8,3%), F6 - 31,2mg (7,6%). Analisados por CG-MS observa-se que a maioria dos compostos identificados nos óleos essenciais das folhas e bulbos e das frações obtidas do OB são compostos organosulfetos (COS). As principais classes de sulfetos identificadas nas diferentes amostras de A. tuberosum, destacam-se os monosulfetos, disulfetos, trisulfetos, tetrassulfetos e sulfinatos. Na avaliação do MIC obtiveram-se atividade do OB de 200ug/mL e das frações mais ativas FI (50ug/mL) e F2 (50ug/mL). Concluii-se que os principais compostos responsáveis pela atividade anti Candida albicans do Allium tuberosum são alil,metil-disulfeto, dimetil-trisulfeto, dialildisulfeto e alil,metil-trisulfeto, presentes no óleo essencial dos bulbos e nas frações FI e F2 / Abstract: Frequently used in folk medicine, the genus Allium include more than 600 species founded in several world regions like Europe, North America, Africa and Asia. The most of species is edible and have a aroma and smell characteristics, being algo used as hypocholesterolemic, anticold and antimicrobial. Among theAllium species,A. tuberosum Rottl. ex Spreng (Liliaceae) belongs to the same family of the garlic, anion and poroallium. In the China, is popularly called "Jiucai" and in Japan, "Nirá" and is also know as "Chinese chive", a important ingredient in the Asiatic culinary. Studies aims determine the properties of Allium spp. as antifungical and aim identify their volatile compounds are described in literature. The essential oils from leaves (OF) and bulbs (OB) ofA. tuberosum were obtained by hydrodistillation in a Clevenger system, yielding 0,15% and 0,12%, respectively. The dichloromethanic extract from bulbs (EB), obtained in a Ultra-Turrax system, presented yield of 3,28%. The minimal inhibitory concentration (MIC) from oils against Candida albicans was: OF (>1000ug/mL), OB (200ug/mL) and EB (250ug/mL). The OB was fractionated in dry column by use of dichloromethane as eluent, when were obtairied six fractions: FI (33%), F2 (3,7%), F3 (3,3 %), F4 (12,6%), F5 (8,3%), F6 (7,6%), evaluated to anti-C. albicans activity. The volatile compounds present in the essential oils, extract and fractions of OB were identified by CG-MS. The major,ity compounds present in the OF, OB and in the FI and F2 from OB were organosulphides from disulphides classes, trisulphides, tetrasulphides and sulphinides, to standing out the allyl, methyl-disulphide, dimethyl-trisulphide, diallyl-disulphide and alil, methyl trisulphide. Significant quantities of limonene and sulphinades and low concentration of other sulphides were founded in EB. The MIC evaluation of fractions obtained from OB revealed a significant increase of activity for FI and F2, with MIC value of 50ug/mL, when compared to OB (200ug/mL). These results indicate that the main compounds from A. tuberosum responsible by anti-Candida activity are allyl, methyl-disulphide, dimethyltrisulphide, diallyl-disulphide and diallyl disulphide, present in higher concentration in OB and in the fractions FI e F2 / Mestrado / Farmacologia, Anestesiologia e Terapeutica / Mestre em Odontologia

Diversos estudos relacionados ao consumo de café na literatura não apresentam um consenso do papel deste alimento na saúde. Esta divergência pode ser o reflexo da utilização do consumo habitual auto-relatado pelos indivíduos como o único fator de exposição avaliado, visto que não existem biomarcadores de consumo, além de diferenças na composição química e na metabolização interindividual dos compostos bioativos (CBAs) da bebida. Desta forma, o presente estudo tem como objetivo identificar as alterações no perfil metabolômico de indivíduos saudáveis após o consumo controlado de café, bem como em extratos de café do tipo tradicional e expresso de diferentes marcas. Participaram deste estudo 35 homens saudáveis divididos entre os grupos café (n = 30) e controle (n = 5). As amostras de soro foram coletadas em jejum e 6, 12 e 24 horas após consumo de café (grupo café) ou água (grupo controle) seguida da extração de metabólitos, derivação com reagentes químicos e avaliação pelo método CG-EM. Posteriormente, os metabólitos foram identificados, selecionados, caracterizados e estatisticamente analisados. A análise metabolômica não direcionada permitiu a identificação de três compostos específicos do café (Caffeine, Quinic acid, m-Hydrocoumaric acid) a partir de 6 horas no grupo café. Além destes compostos, o metabólito Methylmalonic acid também demonstrou ser um candidato à biomarcador sérico da ingestão de café. Por meio das comparações entre os grupos café e controle ao decorrer dos tempos no modelo misto observamos diferentes respostas do perfil metabolômico de aminoácidos, carboidratos e lipídeos, promovidas pelos fatores tempo e grupo como também sua interação. Os aminoácidos 4-Hydroxyproline 1, LAlanine 1, L-Cystine 3, L-Methionine 1 e L-Threonine 2 apresentaram diferentes perfis de comportamento no grupo café ao longo de 24 horas, em relação ao grupo controle. Em paralelo, foram realizadas às análises metabolômicas de dois tipos de café: tradicional (Pilão, Melitta, 3 Corações e Prima Qualitá) e expresso (Nespresso, Dolce Gusto e Café Do Ponto). Após a preparação das bebidas, os extratos foram submetidos aos mesmos procedimentos do estudo de intervenção nutricional. No grupo tradicional, nenhum metabólito exclusivo foi identificado nas 4 marcas, porém o perfil metabolômico das marcas Melitta e 3 Corações foram similares e diferentes das demais. No grupo expresso, os cafés Nespresso e Dolce Gusto mostraram perfis semelhantes e diferentes do Café do Ponto, o qual apresentou exclusivamente Cellobiose 2 e beta- Gentiobiose. A comparação entre os grupos tradicional e expresso demonstrou que seus perfis metabolômicos foram distintos, bem como cada um deles apresentou metabólitos exclusivos com algumas funções celulares e moleculares diferentes. A quantidade dos principais compostos bioativos do café foi diferente entre os dois tipos e suas marcas. A caracterização do metaboloma em um grupo homogêneo de indivíduos saudáveis permitiu identificar candidatos à biomarcadores e alterações no perfil de alguns aminoácidos após a ingestão controlada de café. Assim, a identificação de candidatos à biomarcadores de efeito agudo do café mostra a importância de validar um painel com biomarcadores de alta confiabilidade e que possam colaborar com futuros estudos de intervenção nutricional, não apenas baseado do consumo de café reportado. Além disso, diferentes métodos de preparo do café, tradicional e expresso, bem como as diversas marcas analisadas, apresentaram diferença nos seus perfis metabolômicos. Desta forma, este estudo também pode ressaltar a importância de se considerar não somente a quantidade, mas também o tipo e a marca de café consumido como fatores de exposição em estudos de intervenção nutricional e de associação entre o consumo de café e seus efeitos no organismo / There are several studies associating coffee consumption and diseases, however they are not concordant about the coffee role in health. This divergence may reflect a lack of standard in data acquisition since most of the time the subjects\' self-reported habitual consumption is the only exposure factor evaluated and there is no biomarker. Add, there are differences of coffee beverage bioactive compounds composition and subjects show difference in coffee metabolization resulting in many covaries to be considered in these studies. Our study aimed to identify changes in metabolomic profile of healthy individuals after controlled consumption of coffee, as well as metabolic profile of traditional and espresso coffee beverages from different brands. 35 healthy men were distributed into coffee (n = 30) and control (n = 5) groups. Serum was sampled at fasting and 6, 12 and 24 hours after coffee (coffee group) or water (control group) intake. Metabolites were extracted, derivatized with MSTFA and TMCS, and run in GC-MS. Subsequently, the metabolites were identified using Fiehn Metabolomics Library and NIST, filtered, characterized and statistically analyzed. Untargeted metabolomic analysis identified three specific compounds of coffee (Caffeine, Quinic acid, m-Hydrocoumaric acid) in serum of subjects six hours after coffee intake. In addition to these compounds, Methylmalonic acid showed as a potential biomarker candidate of coffee intake in serum. Comparing coffee and control groups over time in a mixed model, we observed difference in the metabolomic profile related to amino acids, carbohydrates and lipids. 4-Hydroxyproline 1, L-Alanine 1, L-Cystine 3, L-Methionine 1 and L-Threonine 2 showed different profiles in coffee group over 24 hours compared to control group. In parallel to serum samples, we performed metabolomic analysis of the beverage. Two types of coffee were used: traditional powder (Pilão, Melitta, 3 Corações and Prima Qualitá) and capsule espresso (Nespresso, Dolce Gusto and Café Do Ponto). After beverages preparation, extracts were submitted to same metabolites extraction and analysis procedures of serum samples. In traditional coffee group, no exclusive metabolites were identified in four brands, but metabolomic profile of Melitta and 3 Corações were similar between them and different from the others. In espresso coffee group, Nespresso and Dolce Gusto showed similarity and they were different from of Café do Ponto, which presented exclusively Cellobiose 2 and beta-Gentiobiose. The comparison between traditional coffee and espresso coffee groups showed a difference in their metabolomic profiles, as well as each of them presented exclusive metabolites with different cellular and molecular functions. The amount of major bioactive compounds in coffee was different between the two modes of preparation and their brands. The characterization of metabolome in a homogeneous group of healthy individuals allowed the identification of potential biomarkers and showed alterations in some amino acids profile after controlled coffee intake. The identification of candidates for biomarkers of acute coffee effect showed the importance of validating a panel with biomarkers of high reliability and that may collaborate with future studies of nutritional intervention, not only based on the reported coffee consumption. In addition, coffee brewing method and brand of the product resulted in differences in their metabolomic profiles. Thus, this study may also highlight the importance of considering not only quantity, but also the brewing method and brand of coffee consumed as exposure factors in studies of nutritional intervention

Diversos estudos relacionados ao consumo de café na literatura não apresentam um consenso do papel deste alimento na saúde. Esta divergência pode ser o reflexo da utilização do consumo habitual auto-relatado pelos indivíduos como o único fator de exposição avaliado, visto que não existem biomarcadores de consumo, além de diferenças na composição química e na metabolização interindividual dos compostos bioativos (CBAs) da bebida. Desta forma, o presente estudo tem como objetivo identificar as alterações no perfil metabolômico de indivíduos saudáveis após o consumo controlado de café, bem como em extratos de café do tipo tradicional e expresso de diferentes marcas. Participaram deste estudo 35 homens saudáveis divididos entre os grupos café (n = 30) e controle (n = 5). As amostras de soro foram coletadas em jejum e 6, 12 e 24 horas após consumo de café (grupo café) ou água (grupo controle) seguida da extração de metabólitos, derivação com reagentes químicos e avaliação pelo método CG-EM. Posteriormente, os metabólitos foram identificados, selecionados, caracterizados e estatisticamente analisados. A análise metabolômica não direcionada permitiu a identificação de três compostos específicos do café (Caffeine, Quinic acid, m-Hydrocoumaric acid) a partir de 6 horas no grupo café. Além destes compostos, o metabólito Methylmalonic acid também demonstrou ser um candidato à biomarcador sérico da ingestão de café. Por meio das comparações entre os grupos café e controle ao decorrer dos tempos no modelo misto observamos diferentes respostas do perfil metabolômico de aminoácidos, carboidratos e lipídeos, promovidas pelos fatores tempo e grupo como também sua interação. Os aminoácidos 4-Hydroxyproline 1, LAlanine 1, L-Cystine 3, L-Methionine 1 e L-Threonine 2 apresentaram diferentes perfis de comportamento no grupo café ao longo de 24 horas, em relação ao grupo controle. Em paralelo, foram realizadas às análises metabolômicas de dois tipos de café: tradicional (Pilão, Melitta, 3 Corações e Prima Qualitá) e expresso (Nespresso, Dolce Gusto e Café Do Ponto). Após a preparação das bebidas, os extratos foram submetidos aos mesmos procedimentos do estudo de intervenção nutricional. No grupo tradicional, nenhum metabólito exclusivo foi identificado nas 4 marcas, porém o perfil metabolômico das marcas Melitta e 3 Corações foram similares e diferentes das demais. No grupo expresso, os cafés Nespresso e Dolce Gusto mostraram perfis semelhantes e diferentes do Café do Ponto, o qual apresentou exclusivamente Cellobiose 2 e beta- Gentiobiose. A comparação entre os grupos tradicional e expresso demonstrou que seus perfis metabolômicos foram distintos, bem como cada um deles apresentou metabólitos exclusivos com algumas funções celulares e moleculares diferentes. A quantidade dos principais compostos bioativos do café foi diferente entre os dois tipos e suas marcas. A caracterização do metaboloma em um grupo homogêneo de indivíduos saudáveis permitiu identificar candidatos à biomarcadores e alterações no perfil de alguns aminoácidos após a ingestão controlada de café. Assim, a identificação de candidatos à biomarcadores de efeito agudo do café mostra a importância de validar um painel com biomarcadores de alta confiabilidade e que possam colaborar com futuros estudos de intervenção nutricional, não apenas baseado do consumo de café reportado. Além disso, diferentes métodos de preparo do café, tradicional e expresso, bem como as diversas marcas analisadas, apresentaram diferença nos seus perfis metabolômicos. Desta forma, este estudo também pode ressaltar a importância de se considerar não somente a quantidade, mas também o tipo e a marca de café consumido como fatores de exposição em estudos de intervenção nutricional e de associação entre o consumo de café e seus efeitos no organismo / There are several studies associating coffee consumption and diseases, however they are not concordant about the coffee role in health. This divergence may reflect a lack of standard in data acquisition since most of the time the subjects\' self-reported habitual consumption is the only exposure factor evaluated and there is no biomarker. Add, there are differences of coffee beverage bioactive compounds composition and subjects show difference in coffee metabolization resulting in many covaries to be considered in these studies. Our study aimed to identify changes in metabolomic profile of healthy individuals after controlled consumption of coffee, as well as metabolic profile of traditional and espresso coffee beverages from different brands. 35 healthy men were distributed into coffee (n = 30) and control (n = 5) groups. Serum was sampled at fasting and 6, 12 and 24 hours after coffee (coffee group) or water (control group) intake. Metabolites were extracted, derivatized with MSTFA and TMCS, and run in GC-MS. Subsequently, the metabolites were identified using Fiehn Metabolomics Library and NIST, filtered, characterized and statistically analyzed. Untargeted metabolomic analysis identified three specific compounds of coffee (Caffeine, Quinic acid, m-Hydrocoumaric acid) in serum of subjects six hours after coffee intake. In addition to these compounds, Methylmalonic acid showed as a potential biomarker candidate of coffee intake in serum. Comparing coffee and control groups over time in a mixed model, we observed difference in the metabolomic profile related to amino acids, carbohydrates and lipids. 4-Hydroxyproline 1, L-Alanine 1, L-Cystine 3, L-Methionine 1 and L-Threonine 2 showed different profiles in coffee group over 24 hours compared to control group. In parallel to serum samples, we performed metabolomic analysis of the beverage. Two types of coffee were used: traditional powder (Pilão, Melitta, 3 Corações and Prima Qualitá) and capsule espresso (Nespresso, Dolce Gusto and Café Do Ponto). After beverages preparation, extracts were submitted to same metabolites extraction and analysis procedures of serum samples. In traditional coffee group, no exclusive metabolites were identified in four brands, but metabolomic profile of Melitta and 3 Corações were similar between them and different from the others. In espresso coffee group, Nespresso and Dolce Gusto showed similarity and they were different from of Café do Ponto, which presented exclusively Cellobiose 2 and beta-Gentiobiose. The comparison between traditional coffee and espresso coffee groups showed a difference in their metabolomic profiles, as well as each of them presented exclusive metabolites with different cellular and molecular functions. The amount of major bioactive compounds in coffee was different between the two modes of preparation and their brands. The characterization of metabolome in a homogeneous group of healthy individuals allowed the identification of potential biomarkers and showed alterations in some amino acids profile after controlled coffee intake. The identification of candidates for biomarkers of acute coffee effect showed the importance of validating a panel with biomarkers of high reliability and that may collaborate with future studies of nutritional intervention, not only based on the reported coffee consumption. In addition, coffee brewing method and brand of the product resulted in differences in their metabolomic profiles. Thus, this study may also highlight the importance of considering not only quantity, but also the brewing method and brand of coffee consumed as exposure factors in studies of nutritional intervention

Thesis (Ph. D.)(Chemistry)--University of Pretoria, 2003. / Includes bibliographical references.

Diss. (sammanfattning) Linköping : Univ., 2004. / Härtill 6 uppsatser.

Diss. (sammanfattning) Umeå : Univ., 2007. / Härtill 4 uppsatser.