Black tea extracts (hot aqueous, polyphenols and theaflavins) and green tea extracts (hot aqueous, polyphenols, epicatechin, epicatechin gallate, epigallocatechin and epigallocatechin gallate) were tested in nine standardized cell culture assays for comparative cancer chemopreventive properties. Most black and green tea extracts strongly inhibited neoplastic transformation in mouse mammary orga...

The optimum fermentation times of black tea manufactured by two systems of Orthodox and CTC (cut, tear & curl) were investigated by measuring the quality parameters of black tea, like: theaflavin, thearubigin, highly  polymerized substances and total liquid colour during the fermentation stage. Optimum fermentation times from the beginning of fermentation were determined to be 60 min and 15...

There is increasing evidence that black tea polyphenols contribute to vascular health. We have recently shown that regular ingestion of polyphenol-rich black tea over 6 months results in lower systolic and diastolic blood pressure. However, the time course of these effects remains unclear. Therefore, our objective was to determine if short-term effects of tea on blood pressure could contribute ...

BACKGROUND AND OBJECTIVES Postprandial glycemic control is important for prevention of diabetes. Black tea consumption may improve postprandial glycemic control. The major bioactive compounds are polyphenols, black tea polymerized polyphenol (BTPP).This study examined the effect of black tea consumption on postprandial blood glucose and insulin response following sucrose loading in normal and p...

This study evaluates the potential mechanism of action and bioactivity of black tea and black tea pomace for type 2 diabetes prevention via inhibition of carbohydrate hydrolyzing enzymes. Black tea leaves were extracted in hot water and black tea pomace was extracted in 70% acetone. The phenolic content of the water extract (WBT) and pomace acetone extracts (AOBT) were 5.77 and 8.9 mg/mL, respe...

About 75% of the estimated 2.5 milliontons of dried tea harvested annually in the world is manufactured as black tea. Black tea (Camellia sinensis) is one of the most widely popular nonalcoholic beverages consumed by over two-thirds of the world's population, due to its medicinal, refreshing and mild stimulating effects; besides the positive effects, studies have also shown that drinking tea ca...

The quality of black and green commercial tea samples was accessed by physicochemical analysis, mineral analysis and sensory evaluation. Significant variations in physicochemical and organoleptic parameters were observed. The moisture, protein, fat, crude fiber, water extracts and ash contents of the commercial tea samples were found to be in the range of 2.467.47, 0.87-1.141, 0.94-2.15, 11.23-...

BACKGROUND Plants produce secondary metabolites that often possess widespread bioactivity, and are then known as phytochemicals. We previously determined that several phytochemical-rich food-derived preparations were active against pathogenic foodborne bacteria. Trichomonads produce disease (trichomoniasis) in humans and in certain animals. Trichomonads are increasingly becoming resistant to co...

Black tea improves endothelial function in patients with coronary artery disease. We sought to determine the responsible components of black tea and elucidate the underlying cell signaling mechanisms. We exposed porcine aortic endothelial cells to components of black tea and found that the polyphenol fraction acutely enhanced nitric oxide bioactivity. This effect involved endothelial nitric-oxi...

OBJECTIVE To evaluate fluoride and aluminum concentration in herbal, black, ready-to-drink, and imported teas available in Brazil considering the risks fluoride and aluminum pose to oral and general health, respectively. METHODS One-hundred and seventy-seven samples of herbal and black tea, 11 types of imported tea and 21 samples of ready-to-drink tea were divided into four groups: I-herbal t...