Research Of Reducing Weight Effects On Diet-induced Obese Rats By Using Tea Fumigation

With the changes in the people diet and life styles, obesity has become a serious worldwide epidemic. As obesity causes diabetes, hypertension, coronary heart disease and other dieseases, the World Health Organization (WHO) considers obesity and cancer as the most serious diseases to human health in the 21st century. Therefore, the research of anti-obesity has become a major topic of modern medical science.The health benefits of tea have been widely recognized, especially antioxidation, controlling body weight, etc. At present, the research of tea weight loss is mainly concentrated on the feeding and oral tea fusion. I.e. water-solutable compositons in tea have been many researches. However, volatile compounds on weight loss have not been systematically studied and reported yet. Application of fumigation as a novel way to test the anti-obesity effect of tea was conducted in this paper. The new application of tea would also promote the utilization of low-valued tea products and boost tea-related economy.In our study, rats are fed with high-fat diet for establishing animal model of obesity. Fumigation temperature is set as (39±1)℃. Using the three most typical types of tea (Black tea, Green tea, Dark tea):Qimen black tea, Pu-erh green tea and Pu-erh ripe tea. The tea fumigation were applied for 45-day. Low-dose group (3.33%, w/w) and high-dose group (6.67%, w/w) were set as two different dose groups. And Schisandra chinensis is used as the positive control. The main research and conclusions are as follows:1. The results showed that fumigation of Black tea, Pu-erh green tea, Pu-erh ripe tea and Schisandra chinensis were able to reduce body weight, Lee’s index, perirenal fat pad weight, epididymal fat pad weight, fat weight, fat body ratio, serum TC, TG, LDL-C, FBS levels and ALT, AST activity, increasing HDL-C content. The results of liver sections showed fumigation of Black tea, Pu-erh green tea, Pu-erh ripe tea and Schisandra chinensis can protect and refresh the liver damaged by high-fat diet. Fumigation of high-dose Pu-erh ripe tea group showed highest effeciency. The body weight of rats decrease (39.83±8.47) g, the weight is reduced by an average of 7.51%. Meanwhile the high-dose Pu-erh ripe tea group rats’ weight, Lee s index, perirenal fat pad weight, epididymal fat pad weight, fat weight, fat body ratio, TC content, TG content, LDL-C content, FBS, ALT activity, AST activity, HDL-C content is very close to the blank control which are fed with the basal diet. The high-dose Pu-erh ripe tea group rats liver sections under the microscope:the cells arrange in neat, uniform size, the liver tissue injury is significantly recovered, and are very close to the control group rats by inspected with liver sections. Three tea fumigation test groups showed a consistent positive dose-related, high dose group were better, and the three tea fumigation group are better than the positive control group.2. For study the volatile composition of Black tea, Pu-erh green tea, Pu-erh ripe tea and Schisandra chinensis. Automatic HS-SPME combined with GC-MS were used to analyze the volatile components of these samples. Totally 144 volatile components were identified. The mechanism on anti-obesity of these components in tea fumigation still needs further study.This study suggested that the tea fumigation can help to banish glucose and lipid abnormalities, and showed weight loss and liver protection effect in obese rats. This experiment provides valuable reference for further study on the mechanism of tea fumigation to lose weight, reducing blood fat, hypoglycemic effect and protecting liver, etc. The results provide a theoretical basis for the development of a new way to weight control and to expand the use of tea.