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1.
Bioresour Technol ; 323: 124640, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33421829

RESUMO

This study evaluated in-situ co-transesterification of wet spent coffee ground (SCG)/microalgae mixture for enhanced biodiesel production. SCG and microalgae showed lipid contents of 16.0 and 23.6 wt%, respectively. A total of 27 transesterification runs were performed using wet SCG:algae (1:1, w/w) at different temperatures, times, and solvent ratios. Box-Behnken quadratic model suggested 198 °C, 6 mL solvent g-1 biomass, and reaction time of 132 min as the optimum conditions for maximum biodiesel yield. At different SCG/microalgae blend ratios, pure microalgae showed the highest biodiesel yield of 20.15 wt%. Increase of SCG ratio resulted in significant reduction in the biodiesel yield, reaching the lowest value of 11.2 wt% using pure SCG. On the other hand, SCG showed better biodiesel characteristics than microalgae regarding iodine value, cetane number, and oxidation stability. The present results confirmed that SCG-algae blend results in dual effect of enhancing biodiesel yield and quality, comparing to the individual transesterification.


Assuntos
Biocombustíveis , Microalgas , Biomassa , Café , Esterificação
2.
Waste Manag ; 121: 296-330, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33406477

RESUMO

Coffee is one of the most popular beverages in the world, and its popularity is continuously growing, which can be expressed by almost doubling production over the last three decades. Cultivation, processing, roasting, and brewing coffee are known for many years. These processes generate significant amounts of by-products since coffee bean stands for around 50% of the coffee cherry. Therefore, considering the current pro-ecological trends, it is essential to develop the utilization methods for the other 50% of the coffee cherry. Among the possibilities, much attention is drawn to polymer chemistry and technology. This industry branch may efficiently consume different types of lignocellulosic materials to use them as fillers for polymer composites or as intermediate sources of particular chemical compounds. Moreover, due to their chemical composition, coffee industry by-products may be used as additives modifying the oxidation resistance, antimicrobial, or antifungal properties of polymeric materials. These issues should be considered especially important in the case of biodegradable polymers, whose popularity is growing over the last years. This paper summarizes the literature reports related to the generation and composition of the coffee industry by-products, as well as the attempts of their incorporation into polymer technology. Moreover, potential directions of research based on the possibilities offered by the coffee industry by-products are presented.


Assuntos
Café , Polímeros , Bebidas , Tecnologia
3.
Food Chem ; 338: 128045, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33091987

RESUMO

A factorial design with a duplicate in the central point was used to investigate the effect of treating arabica coffee beans with asparaginase. The investigated factors were enzymatic load (1000 and 5000 ASNU/Kg), water percentage (30 and 90%), and hydrolysis time (1 and 3 h). The acrylamide content was determined by UPLC-MS/MS, and the caffeic acid, chlorogenic acid and caffeine concentrations were determined by HPLC-DAD. The statistical analysis was carried out in the R platform using RStudio graphical interface. The results indicated the importance of coffee bean pretreatment with steam, and that the enzyme load reduced the acrylamide content to 65 mg/kg in coffee beans. The predicted reduction was obtained with hydrolysis time of 2 h, water content of 90%, and asparaginase load of 5000 ASNU/kg. The asparaginase treatment did not influence the major bioactive compounds in coffee.


Assuntos
Acrilamida/análise , Asparaginase/metabolismo , Ácidos Cafeicos/análise , Cafeína/análise , Ácido Clorogênico/análise , Café/metabolismo , Ácidos Cafeicos/isolamento & purificação , Cafeína/isolamento & purificação , Ácido Clorogênico/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Café/química , Hidrólise , Extração em Fase Sólida , Espectrometria de Massas em Tandem
4.
Environ Pollut ; 271: 116307, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33360348

RESUMO

The mosquito Aedes aegypti is a primary vector for major arboviruses, and its control is mainly based on the use of insecticides. Caffeine and spent coffee grounds (CG) are potential agents in controlling Ae. aegypti by reducing survival and blocking larval development. In this study, we analyzed the effects of treatment with common CG (CCG: with caffeine), decaffeinated CG (DCG: with low caffeine), and pure caffeine on the survival, behavior, and morphology of the midgut of Ae. aegypti under laboratory conditions. Third instar larvae (L3) were exposed to different concentrations of CCG, DCG, and caffeine. All compounds significantly affected larval survival, and sublethal concentrations reduced larval locomotor activity, delayed development, and reduced adult life span. Damage to the midgut of treated larvae included changes in epithelial morphology, increased number of peroxidase-positive cells (more abundant in DCG-treated larvae), and caspase 3-positive cells (more abundant in CCG-treated larvae), suggesting that the treatments triggered cell damage, leading to activation of cell death. In addition, the treatments reduced the FMRFamide-positive enteroendocrine cells and dividing cells compared to the control. CG and caffeine have larvicidal effects on Ae. aegypti that warrant field testing for their potential to control mosquitoes.


Assuntos
Aedes , Inseticidas , Animais , Cafeína/toxicidade , Café , Inseticidas/toxicidade , Larva , Mosquitos Vetores
5.
Sci Total Environ ; 761: 144192, 2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33352340

RESUMO

The catalytic boron­hydrogen bond break is usually regarded as an important reaction both in the area of environment treatment and hydrogen energy, attracting increasing attention in the past decades. Due to the limitation of conventional noble metal-based catalyst, cost-effective transition metal-based catalysts with high activity have been recently developed to become the promising candidates. Herein, the coffee ground waste was utilized as the biochar substrate loaded with ultrafine NiCoO2 nanoparticles. The abundant function groups on the biochar substrate efficiently adsorbed the metal ions and confined the crystal growth spatially, making the NiCoO2 nanoparticles highly dispersed on the surface. Moreover, the oxygen vacancies were further created in the catalysts by a vacuum-calcination strategy to boost their catalytic activity towards boron­hydrogen bond break both in the systems of 4-nitrophenol reduction by NaBH4 and hydrogen release from NH3BH3. The results indicated that the moderate presence of oxygen vacancies could effectively accelerate the boron­hydrogen bond break and the catalytic activity performed a satisfied stability during several recycles. The theoretical calculation method was adopted to analysis and discuss the mechanism within this process. This design strategy on active catalysts not only offered a novel solution of biowaste resource reuse but also demonstrated the significant role of oxygen vacancies in energy and environmental catalysis.


Assuntos
Boro , Nanopartículas , Carvão Vegetal , Café , Ligação de Hidrogênio
6.
Ecotoxicol Environ Saf ; 209: 111772, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33316726

RESUMO

There are conclusive evidences of selenium (Se) deficiency in Brazilian soils and foods. Brazil is the largest producer and consumer of coffee worldwide, which favors agronomic biofortification of its coffee. This study aimed to evaluate effects of foliar application of three formulations and six rates of Se on antioxidant metabolism, agronomic biofortification and yield of coffee beans. Seven Se concentrations (0, 10, 20, 40, 80, 100 and 160 mg L-1) were applied from three formulations of Se (sodium selenate, nano-Se 1500, and nano-Se 5000). Selenium application up to 40 mg L-1 increased the concentration of photosynthetic pigments such as chlorophylls, pheophytins and carotenoids in coffee leaves. Foliar application of Se ranging from 20 to 80 mg L-1 decreased lipid peroxidation and concentration of hydrogen peroxide, but increased superoxide dismutase, ascorbate peroxidase, catalase and glutathione reductase activities in coffee leaves. These results indicated that foliar Se application stimulates antioxidative metabolism to mitigate reactive oxygen species. Foliar application of 20 mg Se L-1 of sodium selenate increased coffee yield by 38%, and 160 mg Se L-1 of nano-Se 5000 increased dramatically coffee yield by 42%. Selenium concentration in grains ranged from 0.116 to 4.47 mg kg-1 (sodium selenate), 4.84 mg kg-1 (nano-Se 1500) and 5.82 mg kg-1 (nano-Se 5000). The results suggest the beneficial effect of Se on the increment of photosynthetic pigments, antioxidative metabolism, increased coffee yield and nutritional quality of grains. The recommended foliar Se application in this study can mitigate abiotic stressors such as high temperatures resulting in higher yield of coffee plants.


Assuntos
Antioxidantes/farmacologia , Café/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Selênio/farmacologia , Antioxidantes/metabolismo , Ascorbato Peroxidases/metabolismo , Biofortificação/métodos , Catalase/metabolismo , Clorofila/metabolismo , Coffea , Peroxidação de Lipídeos , Oxirredução , Fotossíntese/efeitos dos fármacos , Folhas de Planta/metabolismo , Ácido Selênico/metabolismo , Superóxido Dismutase/metabolismo
7.
Environ Pollut ; 270: 116244, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33321433

RESUMO

This study investigated the competitive adsorption mechanisms of pharmaceuticals (i.e., naproxen, diclofenac, and ibuprofen) toward the pristine and NaOH-activated biochars from spent coffee wastes (SCW) in lake water and wastewater effluent. The kinetic and isotherm studies revealed that the improved physicochemical characteristics and physically homogenized surfaces of the pristine SCW biochar through the chemical activation with NaOH were beneficial to the adsorption of pharmaceuticals (competitive equilibrium adsorption capacity (Qe, exp): NaOH-activated SCW biochar (61.25-192.07 µmol/g) > pristine SCW biochar (14.81-20.65 µmol/g)). The adsorptive removal of naproxen (Qe, exp = 14.81-18.81 µmol/g), diclofenac (Qe, exp = 15.73-20.00 µmol/g), and ibuprofen (Qe, exp = 16.20-20.65 µmol/g) for the pristine SCW biochar showed linear correlations with their hydrophobicity (log D at pH 7.0: ibuprofen (1.71) > diclofenac (1.37) > naproxen (0.25)). However, their Qe, exp values for the NaOH-activated SCW biochar (naproxen (176.39-192.07 µmol/g) > diclofenac (78.44-98.74 µmol/g) > ibuprofen (61.25-80.02 µmol/g)) were inversely correlated to the order of their log D values. These results suggest that the reinforced aromatic structure of the NaOH-activated SCW biochar facilitated the π-π interaction. The calculated thermodynamic parameters demonstrated that the competitive adsorption of pharmaceuticals on the NaOH-activated SCW biochar compared to pristine SCW biochar occurred more spontaneously over the entire pH (5.0-11.0) and ionic strength (NaCl: 0-0.125 M) ranges. These observations imply that the NaOH-activated SCW biochar might be potentially applicable for the removal of pharmaceuticals in lake water and wastewater effluent.


Assuntos
Preparações Farmacêuticas , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Café , Interações Hidrofóbicas e Hidrofílicas , Lagos , Hidróxido de Sódio , Águas Residuárias , Água , Poluentes Químicos da Água/análise
8.
Waste Manag ; 120: 280-289, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33316548

RESUMO

The electrochemical energy storage performance of activated carbons (ACs) obtained from coffee-derived biowastes was assessed. ACs were obtained from spent coffee ground second waste, after polyphenol extraction, by means of a hydrothermal process followed by physical or chemical activation. The resulting materials exhibited microporous structures with a total specific area between 585 and 2330 m2·g-1. Scanning electron microscopy (SEM) revealed a highly porous microstructure in the case of the chemically activated carbons, while physical activation led to a cracked micro-sized morphology. The electrochemical properties of the materials for supercapacitor applications were investigated in 1 M Na2SO4. After chemical activation, the coffee-derived material displayed a capacitance of 84 F·g-1 at 1 A·g-1 in a 1.9 V voltage window, with 70% capacitance retention at 10 A·g-1 and 85% retention after 5000 cycles of continuous charge-discharge. This work demonstrates how coffee secondary biowaste can be conveniently activated to perform as electrochemical energy storage material, contributing to its revalorization and reinsertion in a circular economy.


Assuntos
Carvão Vegetal , Café , Capacitância Elétrica , Eletrodos , Porosidade
9.
Waste Manag ; 120: 322-329, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33340815

RESUMO

Spent coffee grounds (SCG) hydrochar is a second-generation solid waste obtained by hydrothermal carbonization (HTC). Two washed hydrochars from SCG (175 and 185 °C; 12 MPa of N2) were tested as organic amendments of an agricultural soil (Cambic Calcisol), at doses of 1 and 2.5%, in an in vitro assay using Lactuca sativa as a crop plant. The washed hydrochars differ from the SCG in organic carbon (OC) (56 vs 47%), C/N ratio (29 vs 24), polyphenols (186 vs 77 mg GAE/g), pH (4.1 vs 5.8), assimilable P (186 vs 1274 ppm) and K (32 vs 2475 ppm). The particles of washed hydrochars have a lower size and a more porous structure than SCG particles. Higher HTC temperatures generate greater differences with SCG. The effects on the soil of washed hydrochars are similar to SCG, regarding OC, total N, C/N ratio, available K and P contents. The influence of SCG and washed hydrochars on lettuces is also similar: both give rise to plant growth inhibition and increase in the contents of Ca, Mg, Cu, Fe and Mn. Nevertheless, washed hydrochars seem to be more effective in the mobilization of elements in the soil than SCG, which could be attributed to their higher content of polyphenols. For example: Ca (139 mg/100 g with SCG and 160 mg/100 g with hydrochar) and Fe (0.742 mg/100 g with SCG and 1.45 mg/100 g with hydrochar). Therefore, it can be concluded that SCG hydrochars could be used as organic amendments with similar limitations and advantages to SCG.


Assuntos
Café , Solo , Agricultura , Carbono , Características da Família
10.
Food Chem ; 336: 127707, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32763737

RESUMO

Anthocyanins (ACNs) are naturally derived colorants and antioxidants added to manufactured foods. ACNs were encapsulated in nanocomplexes with chitosan hydrochloride (CHC), carboxymethyl chitosan (CMC) and whey protein isolate (WPI). The ACN-loaded CHC/CMC-WPI nanocomplexes (ACN-CHC/CMC-WPI) showed a preferred particle size (332.20 nm) and zeta potential (+23.65 mV) and a high encapsulation efficiency (60.70%). ACN-CHC/CMC-WPI nanocomplexes exhibited a smooth spherical shape by transmission electron microscopy. Fourier transform infrared (FT-IR) and Raman spectroscopy confirmed interactions between the ACNs and the encapsulation materials (CHC/CMC-WPI). The nanocomplexes or the nanocomplexes incorporated into coffee beverage better protected ACNs at high temperature compared to the unencapsulated ACNs. In simulated gastrointestinal fluids, the ACNs in the ACN-CHC/CMC-WPI were more stable and more slower released over time. The nanocomplexes maintained high DPPH and hydroxyl free radical scavenging activities. This study indicated that CHC/CMC-WPI nanocomplexes can improve the thermal stability and slow the release of ACNs added to food products.


Assuntos
Antocianinas/farmacocinética , Quitosana/química , Café/química , Nanoestruturas/química , Proteínas do Soro do Leite/química , Antioxidantes/química , Quitosana/análogos & derivados , Digestão , Humanos , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Temperatura
11.
Bioresour Technol ; 319: 124247, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33254469

RESUMO

Process instability commonly encountered in anaerobic co-digestion (AcoD) of organic fractions of municipal solid wastes (OFMSWs) is addressed by utilizing hydrochar (CB-HTC) and activated hydrochar (ACB-HTC) derived from coffee ground biomass. Addition of CB-HTC or ACB-HTC shortened the lag phase resulting in high biogas yield of 68.57 Nl/kg oTS or 102.86 Nl/kg oTS, respectively within the first week. Improvement in biogas yield (~5% higher than the control) was due to unique properties which prevented washout of consortia of bacteria useful for AcoD and subsequently led to a more stable process. An increase in either OLR [1.0 kg oTS/(m3*d) to 1.5 kg oTS/(m3*d)] or temperature (36.5 °C to 42.5 °C) did not lead to increase in ammonium-nitrogen or TKN in reactors amended with hydrochars. Likewise, ratio of VFA/TA was within 0.2-0.3 after the fourth week in ACB-HTC treated reactor. Addition of ACB-HTC greatly improved nutrient retention in the digestate.


Assuntos
Carvão Vegetal , Café , Anaerobiose , Biocombustíveis , Biomassa
12.
J Environ Manage ; 278(Pt 2): 111541, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33129032

RESUMO

The coffee processing wastewater (CPWW) requires treatment before being disposed of in the environment or reused due to its high organic and inorganic composition and a low pH. The indigenous microbiota from CPWW is highly diverse and could be selected as inoculums in treatment waste plants. Considering the physico-chemical characteristics of wastewater coffee, we elaborate on steps to select the microbial consortium that showed positive impact via decreasing the pollutant parameters of this effluent. The effectiveness was confirmed using wastewater from different origins with different chemical characteristics. A bacterial consortium composed by Serratia marcescens CCMA 1010 and CCMA 1012, Corynebacterium flavescens CCMA 1006, and Acetobacter indonesiensis CCMA 1002 was selected as the inoculums-based phenotypic assays. The mixed inoculum showed a highly active population (11.18 log CFU mL-1), promoting an 85% decrease in biochemical oxygen demand and a 60% decrease in chemical oxygen demand. There was also an 80% reduction in phosphorus and nitrogen. The final pH changed from 6.0 to 7.5. Additionally, the eco-toxicity using Daphnia similis was reduced by more than 59%. The microbial inoculum was efficient in the biological treatment in CPWWs, demonstrating the efficiency and robustness of the selected strains, independent of the physico-chemical characteristics of wastewater.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Acetobacter , Animais , Análise da Demanda Biológica de Oxigênio , Café , Corynebacterium , Eliminação de Resíduos Líquidos
13.
Food Chem ; 338: 127814, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32798818

RESUMO

Analysis of target analytes in food and environmental samples often required sophisticated instrumentation, which restrains the accessibility and portability of the analysis. Herein, we developed an instrument-free approach for rapid quantification of target analytes. The reported filtration-assisted approach enables image analysis of aggregates formed via interaction between analytes and silver nanoparticles (AgNPs). Two model analytes were chosen for aggregating AgNPs, potassium phosphate for neutralizing the charges and a di-thiol molecule (2,2'-(ethylenedioxy) diethanethiol (EDT)) for cross-linking. The mixtures of AgNPs and analytes were filtered onto filter membranes and analyzed using grey color intensity analysis. Based on the AgNPs-EDT platform, we demonstrated the detection of 1 µg/mL acrylamide in instant coffee and biscuit matrices was achievable. The filtration-assisted method provides a simple, fast and inexpensive approach for optical detection and quantification of analytes in food matrices.


Assuntos
Acrilamida/análise , Filtração/métodos , Análise de Alimentos/métodos , Café/química , Análise de Alimentos/instrumentação , Nanopartículas Metálicas/química , Fosfatos/química , Compostos de Potássio/química , Prata/química , Smartphone
14.
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
15.
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
16.
Bioresour Technol ; 322: 124470, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33338944

RESUMO

The effect of oil extraction from spent coffee grounds as a pre-treatment strategy prior to anaerobic digestion besides assessing the feasibility of defatted spent coffee grounds co-digestion with spent tea waste, glycerin, and macroalgae were examined. Mesophilic BMP tests were performed using defatted spent coffee grounds alongside four co-substrates in the ratio of 25, 50, and 75%, respectively. The highest methane yield was obtained with the mono-digestion of defatted spent coffee grounds with 336 ± 7 mL CH4/g VS and the yield increased with the increase in the mass ratio of defatted spent coffee grounds during co-digestion. Moreover, defatted spent coffee grounds showed the highest VS and TS removal at 35.5% and 32.1%, respectively and decreased thereafter. Finally, a linear regression model for the interaction effects between substrates was demonstrated and showed that distinctly mixing defatted spent coffee grounds, spent coffee grounds, and spent tea waste outperforms other triple mixed substrates.


Assuntos
Café , Metano , Anaerobiose , Biocombustíveis , Digestão , Cinética
17.
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
18.
Braz. dent. sci ; 24(1): 1-7, 2021. tab
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1145514

RESUMO

Objective: The aim of this in vitro study was to evaluate the color stability of different bulk fill composite resins after extrinsic staining with coffee. Material and Methods: Forty-eight disk-shaped specimens (6 mm diameter x 4 mm thick) of each composite resin were prepared for color change test. The composite resins were divided into 4 groups (n=12): one conventional composite resin (Filtek Z250) and three bulk-fill composite resins (Filtek Bulk Fill, Aura Bulk Fill, and Opus Bulk Fill). The samples were stained with 20 mL coffee solution for 7 days, with the solution being replaced every 24 h. The color change analysis was performed using a spectrophotometer, according to the CIE Lab formula. Data were analyzed using the Analysis of variance (ANOVA) and Tukey HSD tests (α=0.05). Results: The results revealed significant differences in color change among the composite resins tested (ρ<0.0001). The Aura Bulk Fill and Opus Bulk Fill showed the highest color change values. Conclusion:Thus, all the resins analyzed were susceptible to extrinsic staining with coffee, and the Filtek Bulk Fill showed the lowest color change value (AU)


Objetivo: O objetivo deste estudo in vitro foi avaliar a estabilidade da cor de diferentes resinas compostas bulk fill após coloração extrínseca com café. Material e Métodos: 48 corpos-de-prova em forma de disco (6 mm de diâmetro x 4 mm de espessura) de cada resina composta foram preparados para o teste de alteração de cor. As resinas compostas foram divididas em 4 grupos (n = 12): uma resina composta convencional (Filtek Z250) e três resinas compostas bulk-fill (Filtek Bulk Fill, Aura Bulk Fill e Opus Bulk Fill). As amostras foram coradas com 20 mL de solução de café por 7 dias, sendo a solução substituída a cada 24 horas. A análise da mudança de cor foi realizada em espectrofotômetro, de acordo com a fórmula CIE Lab. Os dados foram analisados por meio dos testes de Análise de Variância (ANOVA) e Tukey HSD (α = 0,05). Resultados: Os resultados revelaram diferenças significativas na mudança de cor entre as resinas compostas testadas (ρ <0,0001). A Aura Bulk Fill e a Opus Bulk Fill apresentaram os maiores valores de alteração de cor. Conclusão: Assim, todas as resinas analisadas foram suscetíveis à coloração extrínseca com café, sendo que a Filtek Bulk Fill apresentou o menor valor de alteração de cor. (AU)


Assuntos
Análise de Variância , Café , Cor , Resinas Compostas , Odontologia
19.
Yakugaku Zasshi ; 140(11): 1351-1363, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-33132271

RESUMO

Epidemiological studies have shown that coffee consumption may be associated with a lower risk of developing several chronic disorders. To elucidate the molecular mechanism of the effects of coffee, we analyzed molecular response upon exposure to coffee extract using cellular and animal models of these diseases. As obesity is recognized as a major risk factor for these chronic diseases, we investigated the effect of coffee on adipogenesis using mouse preadipocyte 3T3-L1 cells. We found that coffee induced proteasomal degradation of IRS-1, leading to reduction of PPARγ expression, a master transcription factor for adipogenesis. Reduction in weight as well as in IRS-1 expression was detected in the fat tissues of the high fat-diet-fed mice when reared with 60% coffee for 7 weeks. As for Alzheimer's disease, we analyzed the effect of coffee on amyloid ß (Aß) production in human neuronal SH-SY5Y cells. We found a 20% reduction in Aß production when treated with 2.5% coffee for 2 d. This reduction was due to proteasomal degradation of BACE1 (ß-secretase), which was activated by protein kinase A. In addition, coffee ameliorates LPS-induced inflammatory responses in RAW264.7 macrophages by reducing NFκB activity and Nrf2 activation. Roasted coffee prevents selenite-induced cataractogenesis by ameliorating antioxidant loss. Pyrocatechol, a component of roasted coffee, also reduced Aß production and exhibits anti-inflammatory effects by a similar mechanism as coffee. Our results suggest that roasting coffee beans to generate pyrocatechol is necessary for the preventive effects of coffee intake on the chronic diseases.


Assuntos
Doença de Alzheimer/prevenção & controle , Catarata/prevenção & controle , Doença Crônica/prevenção & controle , Café , Ingestão de Líquidos/fisiologia , Adipogenia , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Ácido Aspártico Endopeptidases/metabolismo , Catecóis , Células Cultivadas , Café/química , Modelos Animais de Doenças , Manipulação de Alimentos , Temperatura Alta , Humanos , Proteínas Substratos do Receptor de Insulina/metabolismo , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , PPAR gama/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Células RAW 264.7
20.
Braz Oral Res ; 34: e119, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33146315

RESUMO

The aim of this in vitro study was to evaluate the color stability of a bulk-fill (Filtek One Bulk Fill, 3M ESPE) and a conventional (Filtek Z350 XT, 3M ESPE) composite resin light-cured at different distances, before and after being submitted to staining with a coffee solution. Sixty specimens of each composite resin were prepared and light-cured at distances of 0, 2 and 4 mm, using a LED light-curing unit (Valo, Ultradent). The specimens were separated (n = 10) for immersion in either distilled water or coffee solution (10 minutes a day for 8 days) to stimulate staining. Color evaluations were performed before and after immersion in the solutions, according to CIELab (△Eab), CIEDE2000 (△E00) and the Whiteness Index for Dentistry (△WID). Kruskal Wallis and Dunn tests, Mann-Whitney tests and Wilcoxon test were applied (α = 5 %). The a* value for conventional composite resin showed a significant increase after immersion in coffee and distilled water (p < 0.05). Both composite resins showed greater b* values when immersed in coffee than in distilled water, with no significant difference among the light-activation distances (p > 0.05). There was no significant difference for L* among the light-activation distances; both resins showed significant decrease in L* after immersion in coffee (p < 0.05). Color change (△Eab, △E00) and difference in whiteness (△WID) were higher for conventional resin when immersed in the coffee solution at all the light-activation distances. Conventional composite resin presented a higher staining value than bulk-fill composite resin, regardless of the light-activation distance.


Assuntos
Resinas Compostas , Café , Cor , Teste de Materiais
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