Kombucha: A review of substrates, regulations, composition, and biological properties.

Kombucha has been gaining prominence around the world and becoming popular due to its good health benefits. This beverage is historically obtained by the tea fermentation of Camellia sinensis and by a biofilm of cellulose containing the symbiotic culture of bacteria and yeast (SCOBY). The other substrates added to the C. sinensis tea have also been reported to help kombucha production. The type as well as the amount of sugar substrate, which is the origin of SCOBY, in addition to time and temperature of fermentation influence the content of organic acids, vitamins, total phenolics, and alcoholic content of kombucha. The route involved in the metabolite biotransformation identified in kombucha so far and the microorganisms involved in the process need to be further studied. Some nutritional properties and benefits related to the beverage have already been reported. Antioxidant and antimicrobial activities and antidiabetic and anticarcinogenic effects are some of the beneficial effects attributed to kombucha. Nevertheless, scientific literature needs clinical studies to evaluate these benefits in human beings. The toxic effects associated with the consumption of kombucha are still unclear, but due to the possibility of adverse reactions occurring, its consumption is contraindicated in infants and pregnant women, children under 4-years-old, patients with kidney failure, and patients with HIV. The regulations in place for kombucha address a number of criteria, mainly for the pH and alcohol content, in order to guarantee the quality and safety of the beverage as well as to ensure transparency of information for consumers.

Chemical Composition, Production of Secondary Metabolites and Antioxidant Activity in Coffee Cultivars Susceptible and Partially Resistant to Bacterial Halo Blight.

Coffee production is one of the main agricultural activities in Brazil, and several coffee cultivars with disease resistance have already been developed. The secondary metabolites produced by plants are closely associated with defense strategies, and the resistance of coffee cultivars to bacterial halo blight (BHB) can be related to these compounds. Therefore, this study aims to compare a partially resistant coffee cultivar (Iapar-59) and a susceptible cultivar (Mundo Novo 376/4) to BHB (Pseudomonas syringae pv. garcae) in relation to the chemical composition and antioxidant activity of the leaf extracts. In addition, this study determined the total phenolic and flavonoid contents and phenolic profiles of the Iapar-59 leaf extracts of plants inoculated with P. syringae pv. garcae. The Iapar-59 extract showed a higher content of phenolic compounds and flavonoids than the Mundo Novo 376/4 extract. Both cultivars contained gallic, chlorogenic and caffeic acids; however, the highest contents were quantified in the Iapar-59 cultivar. The leaf extracts from the Iapar-59 cultivar exhibited higher antioxidant activity. Higher concentrations of gallic, caffeic and chlorogenic acids and the presence of vanillin were detected in the extract of cultivar Iapar-59 inoculated with P. syringae pv. garcae.

Coffee beverage reduces ROS production and does not affect the organism's response against Candida albicans

Coffee is a mixture of substances with potential beneficial and adverse health effects. Several studies demonstrate the antioxidant effect of the phenolics compounds present in coffee. Neutrophils produce reactive oxygen species (ROS) by activating of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (NOX2), which plays a key role in organism defenseagainst microbial pathogens. Diabetes mellitus patients are more susceptible to bacterial and fungal infections. The present study evaluated the influence of coffee beverage on NOX2 activity and ROS generation and the impact of this effect on phagocytosis and killing of Candida albicansby neutrophils from diabetic and non-diabetic animals. Diabetes mellitus was induced in male Wistar rats using 2% alloxan. Diabetic and non-diabetic animals were divided into groups treated and untreated with coffee drink (7.2 mL/kg/day) or apocyanine (16 mg/kg/day) for 50 days. After 50 days, the animals' glycemic profile was measured by blood glucose and glycated hemoglobin (HbA1c) tests. The generation of ROS in neutrophilic cells was measured by chemiluminescence and cytochrome C reduction assays. C. albicans phagocytosis and death were evaluated by optical microscopy using the May-Grunwald-Giemsa staining method. The coffee drink has not altered the glycemic profile and NOX2 activity of the animals. However, coffee reduced the ROS pool in non-diabetic and diabetic animals, but this activity did not harm the phagocytosis or killing of neutrophils. Treatment with apocyanin decreased ROS production and killing capacity of neutrophils from non-diabetic animals against C. albicans. We suggest that the coffee drink intake prevents oxidative damage and does not impair response of the organism against opportunistic microorganism.

Evaluation of the protective effect of guava fruits and leaves on oxidative stress / Avaliação do efeito protetor de folhas e frutos da goiabeira no estresse oxidativo

Oxidative stress is an imbalance between reactive oxygen species and antioxidant capacity of action. Thus, research, alternative to mitigate the damaging effects of oxidative stress, improving the body´s antioxidant capacity, prevented the disease and its complicatons. The leaves and fruits of guava are rich in the antioxidants. This work aimed to study the effect of flour and ethanolic/acetone extracts leaves and fruits of guava on lipid oxidation in rats with hypercholesterolemic. The flour and extracts decreased leves of triglycerides and non ­ HDL cholesterol and increased in the HDL. Cholesterol levels decreased only leaves and fruits. The activity of GPx decreased in samples serum in all treatments and the SOD only the extracts were effective. There was no difference in levels the MDA in relation hypercholesterolemic control. For the samples of liver, there was no difference in activity SOD. In relation of activity GPx, only the flour was effective. There were differences in levels the MDA of the hypercholesterolemic animals treated with flour and extracts with the animals of the hypercholesterolemic control.

O estresse oxidativo é um desequilíbrio entre as espécies reativas de oxigênio e capacidade antioxidante de ação. Dessa forma, pesquisas buscam alternativas para amenizar os efeitos prejudiciais do estresse oxidativo, melhorando a capacidade antioxidante do organismo, prevenido as enfermidades e suas complicações. As folhas e frutos de goiaba são ricos em antioxidantes. Este trabalho teve como objetivo estudar o efeito da farinha e folhas etanólicos/acetona extratos e frutos de goiabeira na oxidação lipídica em ratos com hipercolesterolemia. A farinha e extratos de folhas diminuiu de triglicérides e colesterol não - HDL e aumento do HDL. Os níveis de colesterol diminuiram apenas folhas e frutas. A actividade da GPx diminuiu em amostras de soro, em todos os tratamentos e a SOD apenas os extratos foram eficazes. Não houve nenhuma diferença nos níveis de MDA no controle da hipercolesterolemia relação. Para as amostras de fígado, não houve diferença na atividade da SOD. Na relação de GPx atividade, apenas a farinha foi eficaz. Houve diferenças nos níveis do MDA dos animais hipercolesterolêmicos tratados com farinha e extratos com os animais do controle hipercolesterolêmica.

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 influence of integral and decaffeinated coffee brews (Coffea arabica L and C. canephora Pierre) on the metabolic parameters of rats fed with hyperlipidemic diet. Thirty male 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, hyperlipidemic diet associated with integral coffee arabica or canephora brews (7.2 mL/kg/day) and hyperlipidemic diet associated to decaffeinated arabica, or canephora brews, using the same dosage. After 41 days, performance analyses were conducted.The rats were then euthanized and the carcasses were used for the analysis of dried ether extract and crude protein. Fractions of adipose tissue were processed for histological analysis. There was a reduction in weight gain and accumulation of lipids in the carcasses, lower diameter of adipocytes and a lower relative weight of the liver and kidneys of rats fed with 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.

The effects of the decaffeination of coffee samples on platelet aggregation in hyperlipidemic rats.

The effect of coffee on cardiovascular diseases is still controversial. It is known that the process of decaffeination may influence the chemical constitution and, therefore, the biological effects of coffee. This study thus evaluated the effects of decaffeination on the levels of total phenols and chlorogenic acids in Coffea arabica L. samples, as well as the effects of ingesting both integral and decaffeinated coffee on the lipid profile and hemostatic and hematological parameters in normal and hyperlipidemic rats. Samples of integral and decaffeinated lyophilized coffee (Coffea arabica L., planted in Brazil) were used for chemical analysis (total phenols, chlorogenic acid and caffeine contents). For the bioassays, coffee beverages were prepared with non-lyophilized samples (10% w/v) and were filtered and administered to animals by gavage (7.2 mL/kg/day) over 30 days. On the 31st day after beginning the treatment with coffee beverages, hyperlipidemia was induced to the animals by administering Triton WR-1339 (300 mg/kg body weight). On day 32, blood was taken to determine the lipid profile, platelet aggregation, prothrombin time, partially activated thromboplastin time and hemogram. The contents of both phenolic compounds and chlorogenic acid in the integral coffee beverage were significantly lower than those in the decaffeinated coffee beverage. The animals treated with Triton WR-1339 presented a mixed hyperlipidemia. Although the decaffeination process caused a relative increase in total phenols and chlorogenic acids, the coffee drinks were unable to change the lipid profile or the hemostatic and hematological parameters in the studied animals.

Influence of coffee brew in metabolic syndrome and type 2 diabetes.

This study aimed to evaluate the effect of coffee drinking on clinical markers of diabetes and metabolic syndrome in Zucker rats. Diabetic Zucker rats with metabolic syndrome and control Zucker rats were used for in vivo tests. The animals received daily doses of coffee drink by gavage for 30 days. After the treatment, the levels of glucose, triglycerides, total cholesterol and fractions, creatinine, uric acid, activity of aspartate aminotransferase and alanine aminotransferase were evaluated. Urea and creatinine levels were also analyzed in urine. By collaborating in the modulation of the metabolic syndrome and diabetes mellitus type 2, coffee drink helped in reducing serum glucose, total cholesterol and triglycerides. The results demonstrate that treatment with roasted coffee drink, because of its hypoglycemic and hypolipidemic effect, is efficient in the protection of animals with metabolic syndrome and diabetes mellitus type 2.

Compostos bioativos e atividade antioxidante do café (Coffea arabica L. ) / Coffee (Coffea arabica L. ) bioactive compounds and antioxidant activity

Conduziu-se este trabalho, com a proposta de avaliar o potencial antioxidante de dois padrões da bebida do café (rio e mole), verdes e torrados, utilizando modelos in vitro. Foram determinados o teor de fenólicos totais, ácido clorogênico (ácido 5-cafeoilquínico) e cafeína das bebidas. A avaliação in vitro do potencial antioxidante foi investigada pelos métodos de captação do radical DPPH e pelo poder redutor de metais. Os dois padrões de bebida do café analisados não apresentaram diferenças quanto aos parâmetros cor, ácido clorogênico e cafeína. Observou-se que houve redução nos valores de ácido clorogênico à medida que os grãos foram torrados. O café verde bebida rio apresentou maior teor de fenólicos totais que o café bebida mole. Nos grãos torrados não foi observada diferença. A bebida do café 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 grãos torrados, quando comparados aos extratos dos grãos verdes. A torração, porém, reduziu o poder redutor das bebidas do café. Os dados obtidos permitem sugerir que, independente da classificação sensorial da bebida, o café apresenta expressiva capacidade sequestrante de radicais livres e poder redutor de metais.

The present work intended to evaluate the antioxidant potential of two coffee sorts (soft and river), green and roasted, in vitro. Phenolic compounds content, chlorogenic acid (5-cafeoyolquinic) and caffeine of the beverages were evaluated. In vitro evaluation of the antioxidant potential was investigated by DPPH radical scavenging assay and by reducing the power of metals. Both sorts of coffee did not present statistical differences for color, chlorogenic acid and caffeine. After roasting, 5-cafeoyolquinic acid levels decreased. River coffee beverage presented greater content of phenolics than the soft coffee beverage. In the roasted coffees no significant difference was observed. All sorts of coffee beverages presented high reducing ability and important scavenging activity of free radicals. The scavenging activity was higher in the roasted samples. The roast process decreased the reducing ability of the coffee beverage. Results allow suggesting that independent of the sort, coffee presents expressive antioxidant activity and reducing ability.