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1.
Biotechnol Appl Biochem ; 70(1): 22-27, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35196743

RESUMO

Tea is a worldwide consumed herbal beverage and it was aimed in this study to reveal the major fractions of green and black tea in order to enlighten the in vitro inhibition potency on the well-known drug metabolizing enzyme CYP2D6 activity. Methylxanthine fractions were extracted from green and black tea and a yield of 0.265 g (1.06%) for 25 g of dried black tea and 0.302 g (1.2%) for 25 g of green tea was calculated. High-performance liquid chromatography analysis represented that the major components of the methylxanthine fractions were caffeine, theobromine, and theophylline. Methylxanthine content of black tea was 368.25 ± 4.6 µg/ml caffeine, 89.30 ± 2.3 µg/ml theobromine, and 3.40 ± 0.5 µg/ml theophylline, whereas that of green tea was 176.50 ± 3.7 µg/ml caffeine, 53.85 ± 1.4 µg/ml theobromine, and 2.06 ± 0.7 µg/ml theophylline. The results of concentration-dependent inhibition studies were 76% green tea, 75% black tea, and 55% caffeine at concentration of 10 mg/ml. The inhibition rates of green and black tea on CYP2D6 activity were 76% and 75%, respectively, where that of quinidine, the well-known inhibitor of CYP2D6, was 82%. Our results indicate that green and black tea is very likely to modify the CYP2D6 enzyme activity.


Assuntos
Camellia sinensis , Camellia sinensis/química , Cafeína/farmacologia , Cafeína/análise , Teofilina/farmacologia , Teofilina/análise , Citocromo P-450 CYP2D6 , Teobromina/farmacologia , Teobromina/análise , Turquia , Chá/química
2.
Proc Natl Acad Sci U S A ; 119(40): e2121821119, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36161917

RESUMO

Cacao seeds, Theobroma cacao, provide the basis for a ceremonially important Mesoamerican food. Past efforts to identify cacao in ceramics focused on highly decorative vessel forms associated with elite ceremonial contexts, creating assumptions as to how cacao was distributed and who could access it. This study examines 54 archaeological ceramic sherds from El Pilar (Belize/Guatemala) of Late Classic (600 to 900 CE) residential and civic contexts representing a cross-section of ancient Maya inhabitants. Identification of cacao in ancient sherds has depended on the general presence of theobromine; we used the discrete presence of theophylline, a unique key biomarker for cacao in the region. Analysis was done by grinding off all outside surfaces to reduce contamination, pulverizing the inner clay matrix, extracting absorbed molecules, and concentrating the extractions. In order to obtain especially high selectivity and low limits of detection, our study utilized the technique of resonance-enhanced multiphoton ionization coupled with laser-desorption jet-cooling mass spectrometry. This technique isolates molecules in the cold gas phase where they can be selectively ionized through a resonant two-photon process. Of the sherds analyzed, 30 samples (56%) were found to contain significant amounts of theophylline and thus test positive for cacao. Importantly, cacao is present in all contexts, common to all Maya residents near and far from centers.


Assuntos
Cacau , Belize , Cacau/anatomia & histologia , Cacau/história , Argila , Guatemala , História Antiga , Sementes/química , Teobromina/análise , Teobromina/história , Teofilina/análise , Teofilina/história
3.
Biomed Chromatogr ; 36(11): e5462, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35881540

RESUMO

The growing evidence has endorsed the view that therapeutic drug monitoring of caffeine for apnea of prematurity is helpful for dose tailoring when the therapeutic response is lacking or toxicity is suspected. However, plasma without caffeine is difficult to obtain. Therefore, a method was developed and validated to measure caffeine and its three primary metabolites (paraxanthine, theobromine and theophylline) using LC-ESI-MS/MS in human plasma and several surrogate matrices. The chromatographic separation of analytes was finally achieved on a Waters Symmetry C18 (4.6 × 75 mm, 3.5 µm) column. Several strategies were successfully applied to overcome the matrix effects: (a) appropriate dilution for sample cleanup; (b) a starting lower proportion of organic phase; and (c) multiple individual stable-labeled isotopic internal standards. The parallelism between the authentic matrix and surrogate matrices was convincing. The recovery of the analytes in both human plasma and rat plasma was acceptable over the linear range (0.500-50.0 µg/ml for caffeine and 0.0100-1.00 µg/ml for three metabolites). The method was successfully applied in 118 samples from 74 preterm infants with apnea of prematurity. The rat plasma or ultrapure water as a surrogate matrix is worthy of recommendation for routine therapeutic drug monitoring of caffeine.


Assuntos
Cafeína , Espectrometria de Massas em Tandem , Animais , Apneia/tratamento farmacológico , Monitoramento de Medicamentos , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Ratos , Espectrometria de Massas em Tandem/métodos , Teobromina/análise , Teobromina/química , Teofilina , Água
4.
Mol Biol Rep ; 49(5): 3965-3973, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35226259

RESUMO

BACKGROUND: Plastic changes of skeletal muscles, such as hypertrophy and atrophy, are dependent on physiological activities and regulated by a variety of signaling pathways, including cyclic adenosine monophosphate (cAMP) pathway. The cAMP inducing agents, such as the ß2-adrenergic agonist clenbuterol, are known to induce muscle hypertrophy, and has been reported to induce slow-to-fast transitions in rat soleus muscle. Theobromine, one of the active components of cacao, functions as an inhibitor of phosphodiesterase and increases cAMP. This study hypothesized that theobromine, like clenbuterol, can induce muscle hypertrophy and influence contractile properties. METHODS AND RESULTS: Male Wistar rats were fed a normal diet or a diet containing 0.05% theobromine for 20 weeks. Using biochemical, anatomical, and physiological techniques, effects of dietary theobromine on skeletal muscles (soleus, extensor digitorum longus, plantaris, and gastrocnemius) were examined. There were no significant differences in body weight, serum levels of proteins and lipids, muscle weights, dry/wet ratio of muscle weights, mitochondrial oxidation enzyme activity of muscles, isometric contractile properties of muscles, and muscle fatigue between control and theobromine-fed rats. Quantitative analysis of mRNA, however, revealed upregulation of myosin heavy chain 2x and myogenic differentiation 1, as previously reported in clenbuterol-treated muscles. CONCLUSION: The long-term theobromine (0.05%) diet in rats had no effect in inducing muscle hypertrophy and in changing contractile properties, although it had some similar effects of clenbuterol on muscle gene expression.


Assuntos
Clembuterol , Agonistas Adrenérgicos beta/metabolismo , Animais , Clembuterol/análise , Clembuterol/metabolismo , Clembuterol/farmacologia , Dieta , Hipertrofia , Masculino , Músculo Esquelético/metabolismo , Ratos , Ratos Wistar , Teobromina/análise , Teobromina/metabolismo , Teobromina/farmacologia
5.
Nat Commun ; 12(1): 5993, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34645808

RESUMO

Metabolic biomonitoring in humans is typically based on the sampling of blood, plasma or urine. Although established in the clinical routine, these sampling procedures are often associated with a variety of compliance issues, which are impeding time-course studies. Here, we show that the metabolic profiling of the minute amounts of sweat sampled from fingertips addresses this challenge. Sweat sampling from fingertips is non-invasive, robust and can be accomplished repeatedly by untrained personnel. The sweat matrix represents a rich source for metabolic phenotyping. We confirm the feasibility of short interval sampling of sweat from the fingertips in time-course studies involving the consumption of coffee or the ingestion of a caffeine capsule after a fasting interval, in which we successfully monitor all known caffeine metabolites as well as endogenous metabolic responses. Fluctuations in the rate of sweat production are accounted for by mathematical modelling to reveal individual rates of caffeine uptake, metabolism and clearance. To conclude, metabotyping using sweat from fingertips combined with mathematical network modelling shows promise for broad applications in precision medicine by enabling the assessment of dynamic metabolic patterns, which may overcome the limitations of purely compositional biomarkers.


Assuntos
Monitoramento Biológico/métodos , Café/metabolismo , Metabolômica/métodos , Suor/química , Adulto , Monitoramento Biológico/normas , Biotransformação , Cafeína/análise , Cafeína/metabolismo , Ácido Clorogênico/análise , Ácido Clorogênico/metabolismo , Cromatografia Líquida , Feminino , Dedos , Humanos , Masculino , Metabolômica/normas , Pessoa de Meia-Idade , Análise de Componente Principal , Espectrometria de Massas em Tandem , Teobromina/análise , Teobromina/metabolismo , Teofilina/análise , Teofilina/metabolismo
6.
Sci Rep ; 11(1): 8119, 2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33854089

RESUMO

Caffeine is the most consumed alkaloid stimulant in the world. It is synthesized through the activity of three known N-methyltransferase proteins. Here we are reporting on the 422-Mb chromosome-level assembly of the Coffea humblotiana genome, a wild and endangered, naturally caffeine-free, species from the Comoro archipelago. We predicted 32,874 genes and anchored 88.7% of the sequence onto the 11 chromosomes. Comparative analyses with the African Robusta coffee genome (C. canephora) revealed an extensive genome conservation, despite an estimated 11 million years of divergence and a broad diversity of genome sizes within the Coffea genus. In this genome, the absence of caffeine is likely due to the absence of the caffeine synthase gene which converts theobromine into caffeine through an illegitimate recombination mechanism. These findings pave the way for further characterization of caffeine-free species in the Coffea genus and will guide research towards naturally-decaffeinated coffee drinks for consumers.


Assuntos
Coffea/genética , Metiltransferases/genética , Proteínas de Plantas/genética , Sequência de Aminoácidos , Cafeína/análise , Cromossomos de Plantas , Coffea/química , Coffea/enzimologia , Comores , Hibridização Genômica Comparativa , Evolução Molecular , Metiltransferases/classificação , Metiltransferases/deficiência , Filogenia , Folhas de Planta/química , Folhas de Planta/enzimologia , Folhas de Planta/genética , Proteínas de Plantas/classificação , Proteínas de Plantas/metabolismo , Alinhamento de Sequência , Análise de Sequência de RNA , Teobromina/análise
7.
Food Chem ; 341(Pt 2): 128249, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33038804

RESUMO

The metabolic profile of Lavado cocoa was characterized for the first time by NMR spectroscopy, then compared with the profiles of fermented and processed varieties, Natural and commercial cocoa. The significant difference in the contents of theobromine and flavanols prompted us to examine the cocoa varieties to seek correlations between these metabolite concentrations and the anti-amyloidogenic activity reported for cocoa in the literature. We combined NMR spectroscopy, preparative reversed-phase (RP) chromatography, atomic force microscopy, in vitro biochemical and cell assays, to investigate and compare the anti-amyloidogenic properties of extracts and fractions enriched in different metabolite classes. Lavado variety was the most active and the catechins and theobromine were the chemical components of cocoa hindering Aß peptide on-pathway aggregation and toxicity in a human neuroblastoma SH-SY5Y cell line.


Assuntos
Cacau/química , Alimentos Fermentados/análise , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/metabolismo , Antioxidantes/química , Cacau/metabolismo , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Flavanonas/análise , Humanos , Espectroscopia de Ressonância Magnética , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Agregados Proteicos/efeitos dos fármacos , Teobromina/análise
8.
Food Chem ; 338: 127834, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32810810

RESUMO

The use of starters during fermentation has been gaining momentum as it can warrant high-quality chocolate. The objective of this study was to investigate the influence of Saccharomyces cerevisiae (Sc) and Pichia kudriavzevii (Pk) during on-farm fermentation on physico-chemical and microbiological characteristics and levels of methylxanthines and bioactive amines of cocoa. Four treatments were used: ScPk (1:1), only Sc, only Pk, and no starter (control). The starters lead to changes throughout fermentation, but provided fermented cocoa with similar pH, titratable acidity, reducing sugars and phenolic compounds. ScPk shortened fermentation time by 24 h. The ScPk fermented and dried cocoa had higher levels of monomeric phenols, methylxanthines, phenylethylamine and lower levels of the putrefactive amines - putrescine and cadaverine (p < 0.05). The results were confirmed by multivariate analysis. Based on these results, the mixture of both yeasts species is a promising starter for cocoa fermentation decreasing duration time and modulating high-quality components.


Assuntos
Cacau/química , Cacau/microbiologia , Chocolate/microbiologia , Pichia , Saccharomyces cerevisiae , Aminas/metabolismo , Cafeína/análise , Catequina/análise , Fazendas , Fermentação , Microbiologia de Alimentos , Concentração de Íons de Hidrogênio , Fenóis/análise , Temperatura , Teobromina/análise , Teofilina/análise , Fatores de Tempo
9.
Anal Chim Acta ; 1124: 71-77, 2020 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-32534677

RESUMO

In vivo sampling and sensitive detection of environmental pollutants and drugs in human body play a crucial role in understanding human health. In this study, in vivo solid-phase microextraction (SPME) swab was fabricated using a SPME fiber and a medical cotton swab for noninvasive sampling and extraction of environmental pollutants and drugs in human oral cavity, nasal cavity and on skin surface. After sampling, SPME was coupled with nano-electrospray ionization mass spectrometry (nanoESI-MS) for desorption, ionization, and detection of the extracted analytes. As a result, limit of detection (LOD) and limit of quantification (LOQ) of nicotine in oral fluid were found to be 1.0 pg/mL (S/N ≥ 3) and 4.0 pg/mL (S/N ≥ 10), respectively. Linear dynamic signal responses of nicotine exhibited excellent linearity (R2 = 0.9996) in human oral fluid ranging from 0.1 to 50 ng/mL. The coefficient of variation (CV) values of SPME swab for five measurements from sample vials and human body were 5.1-6.7% and 22.7-32.6%, respectively. Rapid analysis of a single sample could be completed within 10 min. Overall, our results demonstrated that SPME swab-MS is a promising noninvasive method for enhanced detection of analytes in human body.


Assuntos
Poluentes Ambientais/análise , Boca/química , Nanotecnologia , Pele/química , Microextração em Fase Sólida , Cafeína/análise , Corpo Humano , Humanos , Imidazóis/análise , Nanotecnologia/instrumentação , Nicotina/análise , Microextração em Fase Sólida/instrumentação , Espectrometria de Massas por Ionização por Electrospray/instrumentação , Teobromina/análise , Teofilina/análise
10.
Nat Prod Res ; 34(21): 3154-3157, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31088303

RESUMO

A simple and reliable HPLC method was developed and validated for the quality consistency evaluation of Coffea arabica commercial samples through establishing chromatographic fingerprint and simultaneous determination of bioactive constituents. In the HPLC fingerprint, thirteen common peaks were selected to assess the similarities of coffee samples of different geographical origin. A similarity analysis showed values from 0.434 to 0.950 for the analyzed samples, while quantitation of selected bioactive compounds revealed the highest content of caffeine and the lowest of p-coumaric acid and theobromine in coffee samples. Since phenolic compounds and alkaloids are commonly recognized as natural antioxidants, the antioxidant activity of coffee extracts was also evaluated. The correlation analysis and principal component analysis indicated that the combination of HPLC fingerprint and quantitative analysis can be readily utilized as a quality assessment tool for coffee and other plant products.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Coffea/química , Análise de Alimentos/métodos , Alcaloides/análise , Antioxidantes/química , Cafeína/análise , Cromatografia Líquida de Alta Pressão/estatística & dados numéricos , Análise de Alimentos/estatística & dados numéricos , Qualidade dos Alimentos , Fenóis/análise , Análise de Componente Principal , Reprodutibilidade dos Testes , Sementes/química , Teobromina/análise
11.
Food Chem ; 311: 126021, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31864182

RESUMO

BACKGROUND: Methyl xanthines (MX), known for its psychostimulant effect, occurs mostly in tea and coffee samples. However most of the market available products does not mention the proper amount and quality of MX present where, its consumption in high amount may pose health risks. AIM OF THE STUDY: To develop and validate a fast, efficient and reliable method of MX extraction along with a sensitive, rapid and precise method for simultaneous analysis of MX i.e. Theobromine (TB), Theophylline (TH) and Caffeine (C), with application in commercial tea and coffee samples. MATERIALS AND METHODS: Accelerated Solvent Extraction (ASE) was utilized for the first time to extract MX, whereas UHPLC-DAD was applied in order to quantify MX. RESULTS: ASE resulted a high extract yield (940.22 ± 192.28 mg/g) with optimized conditions of temperature (100 °C) and solvent (MeOH). UHPLC-DAD showed retention time (min) of 1.51 (TB), 1.81 (TH), 2.30 (C) with r2 values (0.980-0.988). Average MX (µg/mL) was as; TB (14.73 ± 20.9), TH (32.05 ± 55.5), C (121.87 ± 32.3). The method application in commercial samples showed a high extract yield with MX concentration (mg/g) as; TB (0.13-0.38), TH (0-0.55), C (7.14-11.20). Temperature and solvent variation showed important correlation with samples in terms of extraction yield. CONCLUSION: ASE-UHPLC/DAD revealed a fast and sensitive method of MX extraction, quantification and quality determination in market available tea and coffee samples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Café/química , Chá/química , Xantinas/isolamento & purificação , Cafeína/análise , Cafeína/isolamento & purificação , Sensibilidade e Especificidade , Solventes/química , Temperatura , Teobromina/análise , Teobromina/isolamento & purificação , Teofilina/análise , Teofilina/isolamento & purificação , Xantinas/análise
12.
Molecules ; 24(16)2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31394755

RESUMO

Caffeine is one of the most widely consumed psycho-stimulants. The study of the beneficial effects of caffeine consumption to decrease the risk of developing several neuropsychiatric pathologies is receiving increasing attention. Thus, accurate and sensitive methods have been developed, mainly by LC-MS/MS, in order to quantify caffeine and its metabolites. These quantifications of caffeine and its metabolites by LC-MS/MS require a considerable effort to select or find a surrogate matrix, without the compounds of interest, to be used in the calibration curves. Thus, we evaluated the possibility of using calibration curves prepared in solvent instead of calibration curves prepared in human plasma. Results show that the calibration curves prepared in solvent and in human plasma were similar by comparing their slopes and interceptions, and the accuracy and precision were within the limits of acceptance for both calibration curves. This work demonstrates that, by using internal standards, it is possible to use a calibration curve in solvent instead of a calibration curve in plasma to perform an accurate and precise quantification of caffeine and theobromine.


Assuntos
Cafeína/análise , Cromatografia Líquida , Espectrometria de Massas em Tandem , Teobromina/análise , Cafeína/sangue , Cafeína/química , Cromatografia Líquida/métodos , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem/métodos , Teobromina/sangue , Teobromina/química , Teofilina/análise , Teofilina/sangue , Teofilina/química
13.
J AOAC Int ; 102(3): 865-871, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30704551

RESUMO

Background: Caffeine, theophylline, and theobromine are methylxanthines commonly found in coffee, tea, cola, and cocoa. Other sources may be soft drinks or energy drinks. All of them are stimulants of the nervous system and can be used for the treatment of some diseases. The three xanthines produce addiction with typical abstinence symptoms. Among young people, the consumption of energy beverages is increasing, and the growing market causes concern about the caffeine intake. To evaluate intake of methylxanthines, their accurate determination can be helpful. Methods: A simple method for their determination without sample pretreatment was applied to beverages, including coffee, tea, cola, and energy drinks. The separation was achieved by LC with UV detection. The method was validated in terms of linearity, LOD and LOQ, accuracy, and reproducibility. Results: The drinks were directly injected after a filtration, and no matrix effect was demonstrated. The procedure proved to be simple, time saving, accurate, and reproducible and may be recommended for reliable assays in routine work. The investigated samples showed a range of caffeine concentration from 100 to 3050 mg/L. Possible intake of methylxanthines from miscellaneous types of drinks was assessed considering the European Food Safety Authority Opinion on the safety of caffeine consumption. Our results were in good agreement with other authors. Conclusions: A fast and accurate method for the simultaneous determination of three xanthynes in beverages was validated. The selected strategy has proved to be fit-for-purpose by applying it to different nervous system stimulant drinks. Highlights: A simple and time saving procedure was proposed for the separation, detection, and quantitation of three methylxantynes in nervous system stimulant drinks. No sample preparation was needed, and speculation could be made about the possible intake of them from beverages.


Assuntos
Cafeína/análise , Bebidas Gaseificadas/análise , Bebidas Energéticas/análise , Teobromina/análise , Teofilina/análise , Cromatografia Líquida de Alta Pressão/métodos , Café/química , Limite de Detecção , Reprodutibilidade dos Testes , Chá/química
14.
Food Chem ; 281: 222-230, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-30658751

RESUMO

Catechins and methylxanthines are natural molecules in guarana (Paullinia cupana) that are associated with antioxidant and stimulatory effects in the human body. There are few natural sources of these antioxidants. The most popular molecule used in foods and beverages is caffeine, which, most of the time, is derived from synthetic sources. In this work, cold hydroalcoholic (CHM), hot hydroalcoholic (HHM), and aqueous enzymatic maceration (AEM) were applied to crude (CG) and waste guarana seeds (WG) to process these materials into natural added-value products with enhanced levels of catechin, epicatechin, epicatechin gallate, caffeine, theobromine and theophylline. The highest level of catechins and methylxanthines was extracted with HHM. Nevertheless, AEM enhanced the global yield in the extract, probably due to the solubilization of other substances. The maceration procedures applied to guarana contributed to the valorization of this plant crop by providing antioxidant sources with clear applications in food and nonfood industries.


Assuntos
Catequina/análise , Paullinia/química , Sementes/química , Xantinas/análise , Antioxidantes/análise , Cafeína/análise , Catequina/análogos & derivados , Fenol/análise , Extratos Vegetais/análise , Teobromina/análise , Teofilina/análise
15.
Food Res Int ; 115: 200-208, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30599932

RESUMO

The use of zero-waste processes to integrate food-waste valorisation into the circular economy equation is currently one of the hottest topics in sustainability research. This goal is still far from being fully achieved despite the release of a number of patents and papers that deal with the topic. The present work aims to valorise cocoa shells, one of the main by-product of the roasting process, in order to enhance the effective extraction of high added value compounds by means of green protocols. The high potential added value of the residual waste has been demonstrated via a direct analytical comparison of extracts and bean composition. A range of raw matrix extraction procedures have been investigated in order to define the best solvent and technology; ultrasound (US) and hydrodynamic cavitation (HC) were compared with conventional methods. The high-energy microenvironments generated by cavitation substantially promote fast biomass deconstruction with low energy consumption. The optimized protocol couples a HC reactor with a ternary water/ethanol/hexane mixture, simultaneously providing a hydrophilic product, which is rich in methylxanthines and polyphenols, and a lipid layer. Sequential milling and sieving pretreatment provided an enriched shell fraction via the partial removal of husk fibres (54.45 vs. 81.36 w/w % total fibres). The disposal of the latter reduces mass balance, but is rerouted into animal feedstock components and crop mulching. The protocols herein reported produce valuable extracts, which are rich in antioxidant flavanols (catechins and epicatechins), theobromine (32.7 ±â€¯0.12 mg/g shells), caffeine (1.76 ±â€¯0.08 mg/g shells) and cocoa butter, in a simple and easy manner. This new valorisation process afforded 20.5 w/w % and 15.8 w/w % hydrophilic and lipophilic fractions, respectively, when scaled up to function in a pilot flow reactor. The fatty acids, obtained in remarkable yield (forming the 96.4 w/w % of the total light part) well match the commercial cocoa butter profile. The antioxidant extract shows an impressive total phenolic content of 197.4 mg/g extract (gallic acid eq.), with a radical scavenging activity of 62.0 ±â€¯3.1 µg/mL (expressed in DPPH EC50). This work should facilitate industrial design for the convenient recovery of cocoa by-products as part of a zero-waste strategy.


Assuntos
Cacau/química , Extratos Vegetais/química , Resíduos , Ração Animal , Antioxidantes/análise , Biomassa , Carboidratos/análise , Catequina/análise , Flavanonas/análise , Indústria Alimentícia , Fenóis/análise , Polifenóis/análise , Solventes , Teobromina/análise , Xantinas
16.
Plant Foods Hum Nutr ; 74(1): 54-60, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30368643

RESUMO

Cocoa beans and cocoa products contain considerable amounts of bioactive compounds. Harvesting cocoa fruit too early or too late may have effects on the phenolic and alkaloid concentrations of the cocoa powder. Fermentation, a primary processing used to transform cocoa beans to cocoa powder, may also influence the contents of bioactive compounds. In this study, proanthocyanidins, the major compounds in cocoa polyphenols, caffeine and theobromine of cocoa beans, were evaluated at different maturities at harvest, and with different fermentation durations, with and without the addition of a commercial enzyme, Pectinex® Ultra SP-L. The amounts of proanthocyanidins, caffeine and theobromine, and the antioxidant capacities of the unfermented cocoa beans increased as the fruits matured. The values ranged from 16.12-27.28 g catechin equivalents (CE)/100 g dry weight (DW); 99.66-173.61 mg/100 g DW; 556.39-948.84 mg/100 g DW; 23.23-26.32 mol Trolox equivalents (TE)/100 g DW, respectively. Prolonged fermentation with or without the addition of pectinase, from three to seven days, significantly reduced the amounts of these compounds present. Fermentation using the enzyme significantly reduced the proanthocyanidin content and antioxidant capacity of the cocoa powder, with the overall means decreasing from 8.93-4.93 g CE/100 g DW and from 15.81-12.95 g mol TE/100 g DW, respectively. Two-way ANOVA analyses showed that the proanthocyanidins, caffeine, theobromine contents and the antioxidant capacity of cocoa beans were strongly dependet to their stages of maturity, fermentation methods and fermentation duration.


Assuntos
Alcaloides/análise , Cacau/química , Cafeína/análise , Fenóis/análise , Compostos Fitoquímicos/química , Teobromina/análise , Antioxidantes/análise , Cacau/crescimento & desenvolvimento , Catequina/análise , Chocolate/análise , Fermentação , Frutas/química , Frutas/crescimento & desenvolvimento , Humanos , Polifenóis/análise , Proantocianidinas/análise
17.
Food Chem ; 278: 261-266, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-30583372

RESUMO

A fast method for the determination of methylxanthines in cocoa products and drugs based on PS-MS/MS under MRM condition has been developed. Analyte ions were generated by applying a high voltage on a paper substrate drenched of sample extract using a small volume (∼15 µL) of spray solvent. The gas phase chemistry of the molecules under investigation has been elucidated. The accuracy values of the methodology ranged from 95 to 110%, while the analytical parameters LOQ, LOD, recovery and reproducibility, calculated analyzing spiked samples, confirmed the consistency of the proposed method. Furthermore, real samples have been analyzed both by the developed methodology and by using a classical HPLC-UV approach obtaining comparable values.


Assuntos
Cacau/química , Cafeína/análise , Espectrometria de Massas em Tandem/métodos , Teobromina/análise , Teofilina/análise , Cromatografia Líquida de Alta Pressão/métodos , Análise de Alimentos/métodos , Limite de Detecção , Preparações Farmacêuticas/análise , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/normas
18.
J Agric Food Chem ; 66(43): 11311-11319, 2018 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-30303011

RESUMO

Hongyacha (HYC) is a type of new wild tea plant discovered in Fujian Province, China. This tea is helpful to the healing or prevention of disease in its original growing area. However, research on this tea is limited. Our results showed that HYC displayed obvious differences in its morphological characteristics compared with Cocoa tea ( Camellia ptilophylla Chang), a famous caffeine-free tea plant in China. Theobromine and trans-catechins, but not caffeine and cis-catechins, were the dominant purine alkaloids and catechins detected in HYC. HYC might contain abundant gallocatechin-(4 → 8)-gallocatechin gallate, 1,3,4,6-tetra- O-galloyl-ß-d-glucopyranose, and (-)-gallocatechin-3,5-di- O-gallate, which were not detected in regular tea. We also found that the TCS1 of HYC was distinct, and the responding recombinant protein exhibited only theobromine synthase activity. The obtained results showed that HYC is a new kind of caffeine-free tea plant and may be used for scientific protection and efficient utilization in the future.


Assuntos
Camellia sinensis/química , Chá/química , Cafeína , Camellia sinensis/classificação , Catequina/análise , China , Teobromina/análise
19.
J Sep Sci ; 41(17): 3424-3431, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29963767

RESUMO

Ternary deep eutectic solvent magnetic molecularly imprinted polymers grafted on silica were developed for the selective recognition and separation of theophylline, theobromine, (+)-catechin hydrate, and caffeic acid from green tea through dispersive magnetic solid-phase microextraction. A new ternary deep eutectic solvent was adopted as a functional monomer. The materials obtained were characterized by FTIR spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, NMR spectroscopy, and powder X-ray diffraction. The practical recovery of the theophylline, theobromine, (+)-catechin hydrate, and caffeic acid isolated with ternary deep eutectic solvent magnetic molecularly imprinted polymers in green tea were 91.82, 92.13, 89.96, and 90.73%, respectively, and the actual amounts extracted were 5.82, 4.32, 18.36, and 3.69 mg/g, respectively. The new method involving the novel material coupled with dispersive magnetic solid-phase microextraction showed outstanding recognition, selectivity and excellent magnetism, providing a new perspective for the separation of bioactive compounds.


Assuntos
Catequina/análise , Impressão Molecular , Microextração em Fase Sólida , Chá/química , Teobromina/análise , Teofilina/análise , Catequina/análogos & derivados , Campos Magnéticos , Polímeros/química , Dióxido de Silício/química , Solventes/química
20.
J AOAC Int ; 101(6): 1781-1787, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29895351

RESUMO

Background: Green analytical chemistry (GAC) aims to eliminate or minimize the amount of hazardous solvents consumed and generated daily worldwide. Considering the environmental impact of all analytical procedures and replacing the polluting methodologies with clean ones is of a paramount interest. Objective: This work aims to develop and validate a sustainable, fast, and economic ultrahigh-performance liquid chromatography method for simultaneous determination of methylxanthines in commercial tea samples as well as to evaluate the greenness profile of the proposed method using two greenness assessment tools: National Environmental Methods Index (NEMI) and analytical Eco-scale. Methods: The method was designed based on applying GAC principles in method development. The green chromatography approach was applied by using benign mobile phases. The chromatographic separation was optimized to minimize sample preparation, achieve short analysis time with low solvent consumption, and minimize waste generation. Results: All the studied analytes were separated in only 1.7 min. The detection limits of the studied analytes ranged from 0.015 to 0.03 mg/L, while LOQs were in the range of 0.05 to 0.1 µg/L with UV detection. The proposed method neither uses nor generates harmful chemicals, it passes the four quadrants of the NEMI greenness profile, and it has a high Eco-scale score. Conclusions: Compared with the reported methods, the proposed method is greener, more economical, and faster; therefore, it can be used as a green alternative to the existing conventional methods for routine analysis of the studied analytes without harming the environment.


Assuntos
Cafeína/análise , Cromatografia Líquida de Alta Pressão/métodos , Química Verde/métodos , Chá/química , Teobromina/análise , Limite de Detecção
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