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1.
Int J Food Microbiol ; 343: 109107, 2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33662694

RESUMO

Starter cultures during fermentation of Coffea arabica var. Mundo Novo processed in open stainless-steel vessels by natural and pulped natural methods were studied. The yeasts Meyerozyma caribbica (CCMA 0198), Saccharomyces cerevisiae (CCMA 0543), Candida parapsilosis (CCMA 0544), and Torulaspora delbrueckii (CCMA 0684) were inoculated separately in two different coffee processes: natural and pulped natural. The qPCR (real-time quantitative polymerase chain reaction) was used as a culture-independent method to monitor the inoculum's permanence. Changes in microbial metabolites (organic acids and volatile) production were evaluated by high-performance liquid chromatography (HPLC) and gas chromatograph-mass spectrometry (GC-MS), respectively. The sensory analysis was assessed in roasted beans. The fermentation lasted 27 h, and the coffee temperature ranged from 16.5 to 24.0 °C. The starter culture population was dominant throughout fermentation. S. cerevisiae (CCMA 0543) and T. delbrueckii (CCMA 0684) presented a higher population in natural processing. However, in pulped natural processing, M. caribbica (CCMA 0198) and C. parapsilosis (CCMA 0544) were the dominant populations. Citric, malic, and succinic acids were naturally present in coffee. Lactic, isobutyric, and isovaleric acids were detected at the end of the fermentation in different treatments. Lactic acid was detected in samples at the end of fermentation in Control and CCMA 0198 treatment. NAT coffee inoculated with CCMA 0684 presented isobutyric acid and isovaleric acid concentrations. Volatile compounds, such as 2,6-diethylpyrazine was detected in treatments inoculated with yeasts, but not in Controls. 2-acetoxymethylfuran was only detected in samples inoculated with CCMA 0198 from both NAT and PN methods. Samples fermented with S. cerevisiae (CCMA 0543) presented the highest sensorial scores in both processing (84.75 and 84.92). The inoculated coffee beans showed higher scores of sweetness, long aftertaste, and greater complexity. The starter cultures influenced the sensorial profiles through the synthesis of specific volatile constituents. However, considering all parameters analyzed, S. cerevisiae (CCMA 0543) would be the most suitable yeast for the var. Mundo Novo processed by both fermentation methods.


Assuntos
Reatores Biológicos/microbiologia , Coffea/microbiologia , Manipulação de Alimentos/métodos , Leveduras/metabolismo , Ácidos/análise , Coffea/química , Fermentação , Sensação , Especificidade da Espécie , Paladar , Compostos Orgânicos Voláteis/análise , Leveduras/classificação , Leveduras/isolamento & purificação
2.
Methods Mol Biol ; 2259: 49-57, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33687708

RESUMO

Proteomics is one of the key approaches to understand plant cell physiology involving the regulation of expression of many genes and metabolite production. Technical advances allowed a deeper characterization of plant proteomes, highlighting the need to study cellular compartments. The apoplast is the cellular compartment external to the plasma membrane including the cell wall, where a broad range of processes take place including intercellular signaling, metabolite transport, and plant-microbe interactions. Due to the fragile nature of leaf tissues, it is a challenge to obtain apoplastic fluids from leaves while maintaining cell integrity, which is particularly true for woody plants. Here, we describe the vacuum infiltration-centrifugation (VIC) method for the extraction of the apoplastic fluid compatible with high-throughput proteomic approaches and biochemical analysis from different woody plants.


Assuntos
Coffea/química , Folhas de Planta/química , Proteínas de Plantas/isolamento & purificação , Vitis/química , Parede Celular/química , Centrifugação/métodos , Proteínas de Plantas/análise , Proteômica/métodos , Vácuo
3.
Food Chem ; 349: 129162, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33550017

RESUMO

Coffee is among the most consumed beverages worldwide. The present study reports on the aroma composition associated with coffee seeds brewing. Aroma of authentic coffee specimens of Coffea arabica and C. robusta alongside with typical products consumed in the Middle East were analyzed using HS-SPME coupled with GC-MS. In addition, multivariate data analysis (MVA) was employed. Results revealed for 102 volatiles with a distinct aroma profile between the different brewing methods. Infusion demonstrated higher esters level, while decoction and maceration were more abundant in sesquiterpenes and terpene alcohols, respectively. Besides, heat-induced products, i.e., 4-vinyl guaiacol was identified as potential roasting index in instant coffee and roasted C. robusta brews. Blending with cardamom further masked the smoky odor of such compounds by its fragrant terpinyl acetate. This study provides the first report on the chemical sensory attributes of Middle Eastern coffee blends and further reveal for the impact of brewing, roasting on its aroma composition.


Assuntos
Coffea/química , Café/química , Manipulação de Alimentos/métodos , Informática , Odorantes/análise , Sementes/química , Coffea/crescimento & desenvolvimento , Análise de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta , Oriente Médio
4.
J Agric Food Chem ; 69(3): 1027-1038, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33433215

RESUMO

To gain comprehensive insight into the interactions of key coffee odorants, like the Strecker aldehydes, acetaldehyde, propanal, methylpropanal, 2- and 3-methylbutanal, and methional, and the nonvolatile fraction of coffee, an untargeted metabolomics approach was applied. Ultra performance liquid chromatography (UPLC)-time of flight (TOF)-mass spectrometry (ESI-) profiling followed by statistical data analysis revealed a marker substance for a coffee beverage spiked with acetaldehyde with an accurate mass of 217.0703 [M - H]-. This compound could be identified as a reaction product of quinic acid (QA) and acetaldehyde linked by acetalization at the cis-diol function of QA. Consequently, the acetalization of aldehydes, QA, 5-O-caffeoyl quinic acid (CQA), and quinic acid γ-lactone (QAL) was investigated by means of model reactions, followed by synthesis, isolation, and structure elucidation via UPLC-TOF-MS and 1D and 2D NMR techniques. UHPLC-MS/MSMRM screening and the quantification of aldehyde adducts in coffee beverages revealed the presence of QA/acetaldehyde, -/propanal, -/methylpropanal, and -/methional reaction products and CQA/acetaldehyde, -/propanal, -/methylpropanal, -/2- and 3-methylbutanal, and -/methional and QAL/acetaldehyde adducts for the first time, in concentrations of 12-270 µg/L for QA/aldehydes, 5-225 µg/L for CQA/aldehydes, and 62-173 µg/L for QAL/acetaldehyde. The sensory characterization of the identified compounds showed bitter taste recognition thresholds of 48-297 µmol/L for CQA adducts and 658 µmol/L for QAL/acetaldehyde, while the QA adducts showed no bitter taste (<2000 µmol/L).


Assuntos
Aldeídos/química , Ácido Clorogênico/química , Coffea/química , Lactonas/química , Ácido Quínico/química , Adulto , Cromatografia Líquida de Alta Pressão , Café/química , Culinária , Feminino , Temperatura Alta , Humanos , Masculino , Estrutura Molecular , Sementes/química , Espectrometria de Massas em Tandem , Paladar , Adulto Jovem
5.
Food Chem ; 348: 129094, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33516995

RESUMO

Effect of in vitro digestion on bioactive compounds, biological activities of coffee pulp extract (CPE) against pathogens and a probiotic (Lactobacillus acidophilus TISTR 1338) was investigated. Total phenolic compound (TPC), chlorogenic acid (CGA), caffeine (CF), total monomeric anthocyanin (TMA), antioxidant and antimicrobial activities of the CPE were determined before and after digestion. After the digestion, the TPC, CGA and CF decreased 7.9, 31.7 and 50.0%, dry weight (dw), respectively. The antioxidant activity decreased 22.6% (DPPH) and 12.4% (FRAP). The CPE inhibited Escherichia coli TISTR 780 and Staphylococcus aureus TISTR 1466 at 150 and 200 mg/mL, respectively. Both CPE and the digested CPE had no effect on the tested probiotics. These results suggest that bioactive compounds of CPE may degrade during in vitro digestion, consequently the antioxidant and antimicrobial properties. Therefore, CPE could be a potential natural antimicrobial for food industry with no effect on the probiotics.


Assuntos
Anti-Infecciosos/química , Antioxidantes/química , Coffea/química , Café/química , Digestão , Extratos Vegetais/química , Água/química , Anti-Infecciosos/metabolismo , Antioxidantes/metabolismo , Extratos Vegetais/metabolismo , Probióticos
6.
Food Chem ; 336: 127701, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32781354

RESUMO

This study presents innovative research for comparison of the effect of the different dehydration techniques and methods of extraction on the antioxidant potential and bioactive compounds of Conilon and Arabica coffee flowers. The compounds were analyzed by high performance liquid chromatography and the antioxidant capacity evaluated by the 2,2'-azinobis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and nitric oxide assays. Among the compounds evaluated, trigonelline, gallic acid, chlorogenic acid, and caffeine were identified, with trigonelline and caffeine being those with the highest concentration. The investigated factors significantly influenced the profile of the bioactive compounds identified, and the antioxidant capacity. The 92 °C infusion of freeze-dried Conilon coffee flowers, in general, showed greater antioxidant capacity by ABTS and DPPH assays, as well as total phenolic content. Lyophilization had a positive influence on maintaining the content of phenolic compounds and antioxidant capacity of the samples. Coffee flowers proved to be a potential raw material for making tea-like drinks.


Assuntos
Antioxidantes/farmacologia , Coffea/química , Flores/química , Alcaloides/análise , Antioxidantes/química , Cafeína/análise , Ácido Clorogênico/análise , Cromatografia Líquida de Alta Pressão , Liofilização , Fenóis/análise , Extratos Vegetais/química
7.
J Sci Food Agric ; 101(1): 65-73, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32608518

RESUMO

BACKGROUND: Coffee is one of the most popular beverages around the world, consumed as an infusion of ground roasting coffee beans with a characteristic taste and flavor. Two main varieties, Arabica and Robusta, are produced worldwide. Furthermore, interest of consumers in quality attributes related to coffee production region and varieties is increasing. Thus, it is necessary to encourage the development of simple methodologies to authenticate and guarantee the coffee origin, variety and roasting degree, aiming to prevent fraudulent practices. RESULTS: C18 high-performance liquid chromatography with fluorescence detection (HPLC-FLD) fingerprints obtained after brewing coffees without any sample treatment other than filtration (i.e. considerably reducing sample manipulation) were employed as sample chemical descriptors for subsequent coffee characterization and classification by principal component analysis (PCA) and partial least squares regression-discriminant analysis (PLS-DA). PLS-DA showed good classification capabilities regarding coffee origin, variety and roasting degree when employing HPLC-FLD fingerprints, although overlapping occurred for some sample groups. However, the discrimination power increased when selecting HPLC-FLD fingerprinting segments richer in discriminant features, which were deduced from PLS-DA loading plots. In this case, excellent separation was observed and 100% classification rates for both PLS-DA calibrations and predictions were obtained (all samples were correctly classified within their corresponding groups). CONCLUSION: HPLC-FLD fingerprinting segments were3 found to be suitable chemical descriptors for discriminating the origin (country of production), variety (Arabica and Robusta) and roasting degree of coffee. Therefore, HPLC-FLD fingerprinting can be proposed as a feasible, simple and cheap methodology to address coffee authentication, especially for developing coffee production countries. © 2020 Society of Chemical Industry.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Coffea/química , Cromatografia Líquida de Alta Pressão/classificação , Cromatografia Líquida de Alta Pressão/instrumentação , Culinária , Análise Discriminante , Geografia , Temperatura Alta , Controle de Qualidade , Sementes/química
8.
Food Chem ; 345: 128823, 2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-33341560

RESUMO

Ten new (1-10) and five known (11-15) ent-kaurane diterpene derivatives were identified from the roasted beans of coffea arabica. Their structures were established by extensive spectroscopic analysis including 1D, 2D NMR (HSQC, HMBC, COSY, and ROESY), HRESIMS, and X-ray diffraction analysis. Compounds 1-3 were three types of rearranged ent-kaurane diterpenes, and compounds 4 and 5 were diterpene esters with a rare 6-hydroxyhexanoyl at C-17. Compounds 6, 8, 14, and 15 showed moderate inhibitory effect on α-glucosidase with IC50 values of 149.92 ± 2.52, 23.23 ± 1.03, 54.58 ± 4.21, 54.16 ± 3.95 µM, respectively, compared to the positive control (60.71 ± 16.45 µM). The results of activity assay showed that diterpenes with the double bond between C-15 and C-16 exhibited stronger α-glucosidase inhibitory activity. Further molecular docking experiments were adopted to discuss the mechanism of activity.


Assuntos
Coffea/química , Diterpenos de Caurano/metabolismo , Diterpenos de Caurano/farmacologia , Inibidores de Glicosídeo Hidrolases/metabolismo , Inibidores de Glicosídeo Hidrolases/farmacologia , Simulação de Acoplamento Molecular , alfa-Glucosidases/metabolismo , Culinária , Diterpenos de Caurano/química , Inibidores de Glicosídeo Hidrolases/química , Espectroscopia de Ressonância Magnética , Conformação Proteica , alfa-Glucosidases/química
9.
Am J Clin Nutr ; 113(2): 370-379, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33330899

RESUMO

BACKGROUND: Epidemiological studies have reported lower risk of cardiovascular disease with moderate coffee consumption. In addition, emerging evidence indicates that consumption of coffee beverages enriched in chlorogenic acids (CGAs) may influence blood pressure and endothelial function, suggesting that the beneficial cardiovascular effect of coffee may relate to its CGA content. OBJECTIVES: We conducted a double-blind randomized crossover trial to test the effect of acute consumption of a decaffeinated green coffee extract (DGCE), rich in CGAs, on endothelial function in healthy subjects. METHODS: We compared 3 different doses of DGCE (302, 604, and 906 mg, respectively) with a placebo. Endothelial function was defined as the percentage change in the internal diameter of the brachial artery in response to flow-mediated dilation (%FMD). In addition, we followed the plasma concentration-time profiles of 25 systemic CGA metabolites over 24 h after DGCE consumption and we explored the relation between systemic concentrations of CGAs and the effect on %FMD. RESULTS: The DGCE formulations containing different amounts of CGAs resulted in dose-proportional increases in overall total polyphenol concentrations. The systemic appearance of total CGAs was biphasic, in agreement with previous results suggesting 2 sites of absorption in the gastrointestinal tract. Compared with the placebo group, a significant FMD increase (>1%) was observed 8.5, 10, and 24 h after consumption of 302 mg DGCE (∼156.4 mg CGAs). The differences with placebo observed in the other 2 groups were not statistically significant. Evaluation of the relation between phenolic exposure and %FMD showed a positive tendency toward a larger effect at higher concentrations and different behavior of CGA metabolites depending on the conjugated chemical position. CONCLUSIONS: We demonstrated an acute improvement in %FMD over time after ingestion of a DGCE, explained at least partly by the presence in the blood circulation of CGAs and their metabolites. This trial was registered at clinicaltrials.gov as NCT03520452.


Assuntos
Ácido Clorogênico/análogos & derivados , Ácido Clorogênico/administração & dosagem , Coffea/química , Vasodilatação/efeitos dos fármacos , Ácido Clorogênico/efeitos adversos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Hidroxibenzoatos/química , Masculino , Pessoa de Meia-Idade
10.
Food Chem ; 340: 127830, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32919355

RESUMO

Procyanidins from coffee pulp are responsible from the limited valorization of this by-product. Information about procyanidin structure is still scarce and imprecise. The aim of this work was to study the native and oxidized procyanidins from coffee pulp with respect to composition and structure. An aqueous acetone extract from coffee pulp was purified using Sephadex LH-20. Butanolysis, phloroglucinolysis and thioglycolysis coupled to HLPC-ESI-MS were applied for the characterization of the native and oxidized procyanidins. The purification allowed to recovery three fractions (aqueous, ethanolic and acetonic) and only acetone fraction showed a high concentration of procyanidins (98%, w/w). HPLC-ESI-MS of procyanidins-rich fraction without any reaction resulted in a UV-Vis chromatogram unresolved typical of the presence of procyanidins. The extracted ion chromatogram and MS2 analysis revealed the presence from dimers to pentamers of native procyanidins. Interestingly, by first time an A-type trimeric procyanidin (m/z of 863) was observed in coffee pulp. In our study, (-)-epicatechin was the constitutive unit of procyanidins with an aDP of 6.8 (oligomeric native procyanidins) according to the phloroglucinolysis assay. Two oxidation markers useful to characterization of oxidized procyanidins were observed in the procyanidins-rich fraction after thioglycolysis, a dimer A2-ext and a molecule that corresponds to a linkage between an extension and a terminal unit. Coffee pulp procyanidins were presented with only a minor class of oxidized procyanidins. As far as we know, this is the first study about characterization of the oxidized procyanidins from coffee pulp.


Assuntos
Biflavonoides/análise , Biflavonoides/química , Catequina/análise , Catequina/química , Coffea/química , Proantocianidinas/análise , Proantocianidinas/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Cromatografia Líquida de Alta Pressão/métodos , Café/química , Glicólise , Oxirredução
11.
Food Chem ; 338: 127821, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32798819

RESUMO

Turkish coffee is a popular hot beverage owing to its delicious taste and pleasant aroma in Turkey. In the present study, key odorants of medium (MRC) and dark roasted Turkish coffee (DRC) brews were studied using GC-MS-Olfactometry. A total of 26 and 28 key odorants were detected in the MRC and DRC samples, respectively, with flavour dilution (FD) factors varying between 4 and 2048. The highest FD factor (2048) was found for 2-ethyl-3,5-dimethylpyrazine and 2-ethyl-3-methyl pyrazine in the MRC and DRC brew samples, respectively. One of the main differences between the two brew samples was the guaiacol with phenolic-burnt odour. A higher amount of chlorogenic acids (CGAs) was determined in the MRC as compared to the DRC using LC-DAD-ESI-MS/MS. According to the sensory analysis, the Turkish coffee sample brewed from the MRC beans had a higher score of general impression and pleasant coffee sensory descriptors as compared to the DRC.


Assuntos
Ácido Clorogênico/análise , Café/química , Odorantes/análise , Adulto , Cromatografia Líquida , Coffea/química , Cor , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Pessoa de Meia-Idade , Olfatometria , Fenóis/análise , Espectrometria de Massas em Tandem , Paladar , Turquia
12.
Food Chem ; 337: 128008, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920267

RESUMO

This study investigated the role of furfuryl alcohol (FFA) in the formation of furfurylthiol (FFT), the most important odorant in roasted coffee, using in-bean and spiking experiments. Green beans were spiked with FFA, and after roasting FFT was quantified by stable isotope dilution analysis. The FFT level in the roasted beans increased dose-dependently with addition of FFA. Additionally, beans were spiked with isotopically labelled d2-FFA which generated isotopically labelled d2-FFT after roasting. However, no labelled furfural was observed. The results unambiguously show that FFA serves as a precursor of FFT in coffee. On the other hand, the data indicate that furfural stems not from oxidation of FFA and plays no major role as precursor for FFT formation during coffee roasting. The suggested formation pathway leads from FFA to the furfuryl cation, then protein-bound S-furfuryl-l-cysteine and by subsequent elimination to FFT.


Assuntos
Coffea/química , Furanos/química , Odorantes/análise , Compostos de Sulfidrila/química , Café , Cisteína/análise , Temperatura Alta
13.
Food Chem ; 337: 128023, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920275

RESUMO

In this study, the effects of fungal fermentation on green canephora coffee beans were evaluated by observing the changes to selected non-volatile parameters before roasting, and subsequently the volatile profile after roasting. Solid-state fermentation (SSF) by Aspergillus spp. and Mucor spp. on green canephora coffee beans was shown to modulate the contents of free sugars, free amino acids and polyphenolic compounds such as caffeoylquinic acids (CQAs). Significant strain-specific differences were observed in the contents of aroma compounds after roasting. A significant increase in pyrazines was observed in the Aspergillus oryzae-fermented samples, while higher levels of furans were detected in the Mucor plumbeus-fermented samples. The present work shows that fungal fermentation of green canephora coffee beans is a potentially promising method for the modulation and improvement of coffee flavour and aroma.


Assuntos
Aspergillus/metabolismo , Coffea/metabolismo , Fermentação , Compostos Orgânicos Voláteis/metabolismo , Coffea/química , Odorantes/análise , Sementes/química , Compostos Orgânicos Voláteis/química
14.
Int J Mol Sci ; 21(24)2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33371201

RESUMO

Caffeic acid (CA) and chlorogenic acid (CGA) are phenolic compounds claimed to be responsible for the metabolic effects of coffee and tea consumption. Along with their structural similarities, they share common mechanisms such as activation of the AMP-activated protein kinase (AMPK) signaling. The present study aimed to investigate the anti-obesity potential of CA and CGA as co-treatment in human adipocytes. The molecular interactions of CA and CGA with key adipogenic transcription factors were simulated through an in silico molecular docking approach. The expression levels of white and brown adipocyte markers, as well as genes related to lipid metabolism, were analyzed by real-time quantitative PCR and Western blot analyses. Mechanistically, the CA/CGA combination induced lipolysis, upregulated AMPK and browning gene expression and downregulated peroxisome proliferator-activated receptor γ (PPARγ) at both transcriptional and protein levels. The gene expression profiles of the CA/CGA-co-treated adipocytes strongly resembled brown-like signatures. Major pathways identified included the AMPK- and PPAR-related signaling pathways. Collectively, these findings indicated that CA/CGA co-stimulation exerted a browning-inducing potential superior to that of either compound used alone which merits implementation in obesity management. Further, the obtained data provide additional insights on how CA and CGA modify adipocyte function, differentiation and lipid metabolism.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Adipócitos Marrons/citologia , Adipogenia , Ácido Clorogênico/farmacologia , Coffea/química , Regulação da Expressão Gênica/efeitos dos fármacos , PPAR gama/metabolismo , Adipócitos Marrons/efeitos dos fármacos , Adipócitos Marrons/metabolismo , Humanos , Lipólise , Transdução de Sinais
15.
Molecules ; 26(1)2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33375091

RESUMO

Coffee is rich in caffeine (CF), chlorogenic acid (CGA) and phenolics. Differing types of coffee beverages and brewing procedures may result in differences in total phenolic contents (TPC) and biological activities. Inflammation and increases of platelet activation and aggregation can lead to thrombosis. We focused on determining the chemical composition, antioxidant activity and inhibitory effects on agonist-induced platelet aggregation and cyclooxygenase (COX) of coffee beverages in relation to their preparation method. We prepared instant coffee and brewed coffee beverages using drip, espresso, and boiling techniques. Coffee extracts were assayed for their CF and CGA contents using HPLC, TPC using colorimetry, platelet aggregation with an aggregometer, and COX activity using ELISA. The findings have shown all coffee extracts, except the decaffeinated types, contained nearly equal amounts of CF, CGA, and TPC. Inhibitory effects of coffee extracts on platelet aggregation differed depending on the activation pathways induced by different agonists. All espresso, drip and boiled coffee extracts caused dose dependent inhibition of platelet aggregation induced by ADP, collagen, epinephrine, and arachidonic acid (ARA). The most marked inhibition was seen at low doses of collagen or ARA. Espresso and drip extracts inhibited collagen-induced platelet aggregation more than purified caffeine or CGA. Espresso, boiled and drip coffee extracts were also a more potent inhibitors of COX-1 and COX-2 than purified caffeine or CGA. We conclude that inhibition of platelet aggregation and COX-1 and COX-2 may contribute to anti-platelet and anti-inflammatory effects of espresso and drip coffee extracts.


Assuntos
Coffea/química , Café/química , Inibidores de Ciclo-Oxigenase/química , Inibidores de Ciclo-Oxigenase/farmacologia , Inibidores da Agregação de Plaquetas/química , Inibidores da Agregação de Plaquetas/farmacologia , Ácido Clorogênico/química , Ácido Clorogênico/farmacologia , Cromatografia Líquida de Alta Pressão , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Agregação Plaquetária/efeitos dos fármacos
16.
PLoS One ; 15(8): e0237265, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32841240

RESUMO

Roasting is the most common method of processing coffee. During roasting, aromatic compounds are generated due to various reactions, which are important for developing color, flavor and aroma. Acrylamide is an undesirable carcinogenic substance that is metabolically activated and formed during the coffee roasting process. Coffea arabica was first found in Ethiopia, and Ethiopia can produce a large volume of coffee. The major coffee-producing areas in Ethiopia are Hararghe, Sidama, Gimbi/Nekemte, Yergachefe and Limu. The primary purpose of this study was to quantify the acrylamide contents of brewed and roasted coffee collected from street coffee sellers and industrial processors found in Addis Ababa, Ethiopia, and optimize the roasting conditions for Sidama coffee. The acrylamide contents were determined by HPLC using a DAD at 210 nm, the antioxidant property were examined using a UV-spectrophotometer, and moisture and nutrient composition of coffee was determined using the method described by the AOAC (Association of Official Analytical Chemists). The roasting temperature and time were optimized based on the acrylamide content, nutritional composition and antioxidant property of the coffee using central composite design. The roasting temperature and time significantly affected (p<0.05) the acrylamide level, nutritional composition and antioxidant property of the coffee. The acrylamide contents of street and industrial processed powdered coffee were 346 ±19 to 701±38µg/kg and 442±14 to 906±7µg/kg, respectively. Brewed coffee from street vendors and industrial processing had acrylamide contents of 25±2 to 49±1µg/L and 63±2 to 89±4µg/L, respectively. The EC50 values for scavenging radicals for the optimized coffee ranged from 171±0 to 111±4 µg/L. The optimal roasting temperature and time were 190°C and 6 minutes, at this temperature and time the acrylamide content decreased, and the antioxidant and nutritional compositions of the coffee improved.


Assuntos
Acrilamida/análise , Antioxidantes/análise , Coffea/química , Café/química , Nutrientes/análise , Manipulação de Alimentos/métodos , Tecnologia de Alimentos/métodos , Temperatura Alta , Sementes/química
17.
Complement Ther Med ; 51: 102424, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32507437

RESUMO

BACKGROUND AND AIM: Two meta-analyses summarized data on the effects of green coffee extract (GCE) supplementation on anthropometric measures. However, the accuracy of those meta-analyses is uncertain due to several methodological limitations. Therefore, we aimed to conduct a comprehensive systematic review and dose-response meta-analysis to summarize all available evidence on the effects of GCE supplementation on anthropometric measures by considering the main limitations in the previous meta-analyses. METHODS: We searched available online databases for relevant publications up to January 2020, using relevant keywords. All randomized clinical trials (RCTs) investigating the effects of GCE supplementation, compared with a control group, on anthropometric measures [including body weight, body mass index (BMI), body fat percentage, waist circumference (WC) and waist-to-hip ratio (WHR)] were included. RESULTS: After identifying 1871 studies from our initial search, 15 RCTs with a total sample size of 897 participants were included in the systematic review and meta-analysis. We found a significant reducing effect of GCE supplementation on body weight (weighted mean difference (WMD): -1.23, 95 % CI: -1.64, -0.82 kg,P < 0.001), BMI (WMD: -0.48, 95 % CI: -0.78, -0.18 kg/m2, P = 0.001), and WC (WMD: -1.00, 95 % CI: -1.70, -0.29 cm, P = 0.006). No significant effect of GCE supplementation on body fat percentage and WHR was seen. In the dose-response analyses, there was no significant association between chlorogenic acid (CGA) dosage, as the main polyphenol in green coffee, and changes in anthropometric measures. CONCLUSION: We found that GCE supplementation had a beneficial effect on body weight, BMI and WC. It provides a cost-effective and safe alternative for the treatment of obesity. Additional well-designed studies are required to further confirm our findings.


Assuntos
Índice de Massa Corporal , Peso Corporal/efeitos dos fármacos , Coffea/química , Suplementos Nutricionais , Extratos Vegetais/administração & dosagem , Circunferência da Cintura/efeitos dos fármacos , Adulto , Relação Dose-Resposta a Droga , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
18.
Food Chem ; 331: 127329, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32559595

RESUMO

As the most consumed beverage in the world, the material basis of the sensory quality for roasted coffee beans has always received much attention. The objective of the present study was to clarify the physical morphology changes, main chemical ingredients and cupping scores of arabica coffee beans of different roasting degrees, by scanning electron microscopy (SEM), nuclear magnetic resonance (NMR) and sensory analysis, respectively. Statistical analysis of the data by multivariate analysis demonstrated that trigonelline, sugars, malate, quinic acids, γ-butyro-lactone and acetate have the potential to be new roasting markers. Additionally, in all the sensory indicators, body and acidity were found to be susceptible to roasting degree. Basing on cluster heatmap and sensory molecular network, the complex relationships between sensory indicators and ingredients were discussed. The results of partial least squares regression (PLSR) showed that the content of the main coffee ingredients can be used to predict the body score.


Assuntos
Coffea/química , Café/química , Manipulação de Alimentos , Temperatura Alta , Sementes/química , Paladar
19.
Food Chem ; 329: 127129, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32497844

RESUMO

The acknowledged marker of Robusta coffee, 16-O-methylcafestol (16-OMC), can be quantified by NMR as a mixture with 16-O-methylkahweol (16-OMK), which accounts for approximately 10% of the mixture. In the present study, we detected and quantified 16-O-methylated diterpenes (16-OMD) in 248 samples of green Coffea arabica beans by NMR. We did not observe any differences between genotypes introgressed by chromosomal fragments of Robusta and non-introgressed genotypes. Environmental effects suggesting a possible protective role of 16-OMD for adaptation, as well as genotypic effects that support a high heritability of this trait were observed. Altogether, our data confirmed the presence of 16-OMD in green Arabica at a level approximately 1.5% that of a typical Robusta, endorsing the validity of 16-OMD as a marker for the presence of Robusta.


Assuntos
Coffea/genética , Diterpenos/química , Coffea/química , Café/química , Café/genética , Cor , Genótipo , Espectroscopia de Ressonância Magnética , Metilação , Estrutura Molecular , Sementes/química , Sementes/genética
20.
Food Chem ; 327: 127012, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32464457

RESUMO

Coffee is considered an important source of organic nutrients and minerals, and these resources are strongly affected by agricultural management. Among the minerals, the element Mg is important, which is essential for both plants and humans. In this work, the effects of agricultural management on the absorption and storage of Mg by commercial, ground, roasted Arabica coffee were investigated. For this purpose, some Mg and P fractions were evaluated. It was observed that Mg stored in the grain was concentrated in the inorganic fraction, with an average extraction of 102% and in conventional samples and 119% in organic samples. These results suggest that in these samples Mg is probably largely presented as different inorganic salts. Phytate and organic acid salts are two possibilities discussed in this work that could explain this hypothesis. This can be corroborated by the extraction of Mg in the infusion of hot water.


Assuntos
Agricultura/métodos , Coffea/química , Coffea/crescimento & desenvolvimento , Café/química , Magnésio/análise , Brasil , Fracionamento Químico , Humanos , Agricultura Orgânica , Fósforo/análise , Sementes/química , Solubilidade , Água
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