Adriene Ribeiro Lima

Compostos bioativos do café: atividade antioxidante in vitro do café verde e torrado antes e após a descafeinação

This study aimed to evaluate the effect of coffee decaffeination with dichloromethane on the in vitro antioxidant activity of this matrix. It were determined the content of total phenolics, chlorogenic acid and caffeine of the coffee samples. The assessment of the antioxidant potential was investigated by DPPH radical scavenging method, reducer power and Fe2+chelation activity. The process of decaffeination and roasting caused changes in the levels of the compounds investigated. The results show that the decaffeination by the dichloromethane method reduces the in vitro antioxidant potential of coffee.

Compostos bioativos e atividade antioxidante do café (Coffea arabica L.)

Conduziu-se este trabalho, com a proposta de avaliar o potencial antioxidante de dois padroes da bebida do cafe (rio e mole), verdes e torrados, utilizando modelos in vitro. Foram determinados o teor de fenolicos totais, acido clorogenico (acido 5-cafeoilquinico) e cafeina das bebidas. A avaliacao in vitro do potencial antioxidante foi investigada pelos metodos de captacao do radical DPPH e pelo poder redutor de metais. Os dois padroes de bebida do cafe analisados nao apresentaram diferencas quanto aos parâmetros cor, acido clorogenico e cafeina. Observou-se que houve reducao nos valores de acido clorogenico a medida que os graos foram torrados. O cafe verde bebida rio apresentou maior teor de fenolicos totais que o cafe bebida mole. Nos graos torrados nao foi observada diferenca. A bebida do cafe independente da qualidade sensorial apresentou alto poder redutor e importante atividade sequestrante de radicais livres. A atividade sequestrante de radicais livres foi significativamente superior nas amostras obtidas a partir dos graos torrados, quando comparados aos extratos dos graos verdes. A torracao, porem, reduziu o poder redutor das bebidas do cafe. Os dados obtidos permitem sugerir que, independente da classificacao sensorial da bebida, o cafe apresenta expressiva capacidade sequestrante de radicais livres e poder redutor de metais.

Effect of decaffeination of green and roasted coffees on the in vivo antioxidant activity and prevention of liver injury in rats

Decaffeination and roasting affects the composition of the chlorogenic acids in coffee, which have antioxidant potential. The aim of this study was to evaluate the effects of coffee decaffeination on the in vivo antioxidant activity and the prevention of liver damage. The Wistar rats received intraperitoneal doses of carbon tetrachloride and daily doses of Arabica coffee brews (whole and decaffeinated, both green and roasted) by gavage for fifteen days. The activity of liver marker enzymes aspartate aminotransferase, alanine aminotransferase and serum albumin were measured as well as the quantification of the thiobarbituric acid reactive species and the content of liver total lipids. Aspartate aminotransferase and alanine aminotransferase are good indicators of liver damage: the results showed that all studied coffee brews decreased the activity of aspartate aminotransferase and alanine aminotransferase, and liver levels of thiobarbituric acid reactive species and total lipids. The compounds presents in coffee brews are able to decrease the hepatic lipid peroxidation induced by carbon tetrachloride, making a significant hepatoprotective effect, in accordance with the liver function tests. The coffee brews are hepatoprotective regardless of the decaffeination process and our results suggest a better protection against liver damage for the roasted coffee brews compared with green coffee brews.

Atividade antioxidante in vitro e in vivo de café bebida mole

O objetivo deste trabalho foi determinar a atividade antioxidante do cafe, bebida mole, in vivo e in vitro, antes e apos a torracao. Para a analise da atividade antioxidante in vitro, foram utilizados os metodos de sequestro de radicais livres (DPPH) e de atividade quelante de ions Fe2+. Foram utilizados, para o ensaio in vivo, ratos Zucker diabeticos, portadores de sindrome metabolica, e ratos Zucker controle. Os animais receberam doses diarias das bebidas de cafe, por gavagem, por 30 dias. Apos o tratamento, foi realizada a avaliacao de peroxidacao lipidica. As amostras torradas apresentaram a maior percentagem de sequestro de radicais livres. As concentracoes nas amostras de cafe verde e torrado foram similares as do padrao Trolox. Das amostras torradas, a torracao media se destacou com maior atividade quelante de ions Fe2+. Os cafes verdes mostraram maior poder quelante do que os torrados. Compostos presentes no extrato diminuiram a lipoperoxidacao hepatica e renal que e comum em casos de diabetes e sindrome metabolica. O cafe apresenta atividade antioxidante e protege o figado e os rins dos animais contra a lipoperoxidacao comumente presente em quadros de diabetes mellitus tipo 2 e sindrome metabolica.

Compostos bioativos em café integral e descafeinado e qualidade sensorial da bebida

The aims of this study were to determine the sensorial quality of both decaffeinated and whole coffee (Coffea arabica), the levels of bioactive compounds, before and after toasting, and bioactive compound stability after beverage extraction. The sensorial analysis was accomplished according to the official Brazilian method for coffee classification. The analyses of caffeine, trigonelline and chlorogenic acid were performed by high performance liquid chromatography. The experimental design was completely randomized with split plot using four types of coffee, five times of analyses and three replicates for each treatment. In the sensorial analysis, it was observed that the sensorial characteristics present in the whole sample were lost after the decaffeination process. For trigonelline, no significant differences were found among the whole and decaffeinated samples. For the samples of toasted whole and green decaffeinated coffee, trigonelline did not vary until 4 hours after the extraction. There was a significant reduction in the concentration of chlorogenic acid after toasting, after the decaffeination process, and over the extraction time. For caffeine, there were no significant differences after toasting or even with the time after extraction. Decaffeination and toasting processes affected the sensorial quality of coffee and altered the concentration of bioactive compounds.

Influence of integral and decaffeinated coffee brews on metabolic parameters of rats fed with hiperlipidemic diets

The objective of this study was to evaluate the inf luence of integral and decaffeinated coffee brews (arabica L and C. canephora Pierre) on the metabolic paramet ers of rats fed with hyperlipidemic diet. Thirty ma le Wistar rats (initial weight of 270 g ± 20 g) were used in the study, which were divided into six groups five each. The treatments were normal diet, hyperlipidemic diet, h yperlipidemic diet associated with integral coffee arabica or canephora brews (7.2 mL/kg/day) and hyperlipidemic diet associated to decaffeinated arabica, or caneph ora brews, using the same dosage. After 41 days, performance a nalyses were conducted.The rats were then euthanize d and the carcasses were used for the analysis of dried ether extract and crude protein. Fractions of adipose ti ssue were processed for histological analysis. There was a re duction in weight gain and accumulation of lipids i n the carcasses, lower diameter of adipocytes and a lower relative weight of the liver and kidneys of rats fwith hyperlipidemic diet associated with integral coffee brew. Integral coffee brew reduced the obesity in the rats receiving hyperlipidemic diet, but the same effect did not occur with the decaffeinated types.