Research And Evaluation Of Hypoglycemic Effect Of Compound Black Tea Drink

Dark tea is famous in the world because of its anti-hyperlipemia effect. But dark tea has a low content of theaflavins and catechins. Gynostemma Pentaphgllum (Thunb.) Makino is a kind of Chinese herbal medicine to cure hyperlipemia. In this research, a kind of compound beverage was created by adding theaflavins, catechins and gypenosides into dark tea. The compound dark tea beverage would offer a new idea for hyperlipdemic treatment.First, it’s hard to evaluate the potential anti-hyperlipemia effects of dark tea because of its diversity. In order to explore a simple and convenient method to evaluate the anti-hyperlipemia effects of dark tea, a model based on the components of sixteen samples was built by principal component analysis. The extractions of dark tea were assessed for the lipid-lowering potential when administered conditions contained oleic acid to establish the model of steatosis HepG2in vitro. Based on the cell viability test(MTT value), lipid clearance was used to evaluate the effect of extractions on steatosis HepG2. The result shows:a model of steatosis HepG2in vitro was established in the DMEM nutrient fluid contained1%BSA and1mmol/L oleic acid after24hours The physiological characteristics of the steatosis were stable. If the model of steatosis HepG2was used for evaluate the anti-hyperlipemia effects in vitro, it might reduce the length of test cycle. The lipid lowering experiments in vitro showed a consistency with the principal component analysis model prediction. So the principal component analysis model on potential anti-hyperlipemia effects of dark tea is objective and sensitive.Then, based on the model of steatosis HepG2, lipid clearance was used to evaluate the effect of Cs, TFs and GPs on lipid lowering. The response surface methodology based on a Box-Behnken experimental design was used to optimize the density of the three extractions for combined lipid-lowering in vitro. The result indicated that Cs, TFs and GPs showed a significant inhibitory effect on lipid clearance in HepG2cells. The ability of lipid lowering was significant promoted when the three extractions acted on HepG2at the same time. The best concentration was:TFs90.00μ.g/mL, Cs59.40μg/mL and GPs76.06μg/mLWhen the concentration is extraction of dark tea1000μ.g/mL, TFs90.00μg/mL. Cs59.40μg/mL and GPs76.06μg/mL, the compound beverage have the best sense organ quality. The maximal tolerance dose of the compound beverage was3.26g/kg·BW in mice. At last, to observe the anti-hyperlipemia potential of the compound beverage, all the rats were fed with high fat diet to establish model of hyperlipidemia. The beverage contained theaflavins, catechins, gypenosides and dark tea was used to treat the hyperlipemia rats. Blood-lipid content, activity of the enzyme related with lipid metabolism, weight and liver weight were tested to observe the anti-hyperlipemia effect. The results indicate that the compound tea beverage showed a significant effect in lowering TC, TG and LDL-C levels, raising HDL-C level. The compound beverage also lowered the activity of AST, the weight and blood viscosity of rats. So the compound beverage could regulate blood-lipid level, losing weight, protecting liver and reducing blood viscosity on hyperlipemia rats. The low dose was the most effective on protecting liver, and the middle dose was the most effective on lowering blood viscosity. Drinking of the compound beverage could have contributed to regulate blood-lipid level in everyday life, but we also should keep diet balance and exercising.