Changes Of Polysaccharide During The Process Of Oolong Tea And Its Immune Mechanism On Diabetes Mice

In this paper, the influence of cultivar, season and procedure on Oolong tea polysccharide content, components and biological activities was studied. Besides, immunity mechanism of tea polysaccharide with high activity was assayed. 1. Cultivar, season and process could influence the content, compositions and biological activity of Oolong tea polysaccharide(OTPS).The content of polysaccharide in Oolong tea made with cultivar DaYeOolong was superior to that of cultivar FuDingDaBai, and uronic acid and protein showed the same tendency, while neutral sugar in former was inferior to that in latter. The content and compositions of polysaccharide could be influenced by season. The content of polysaccharide and its neutral sugar reached highest in Spring, the following were in Summer and Autumn, but uronic acid was highest in Summer , the following were Autumn and Spring,. During the process of Oolong tea, the content of polysaccharide and its neutral sugar, uronic acid, protein presented downward trend, particularly after the third shaking. As far as biological activity was concerned, the effects of OTPS extracted from cultivar FuDingDaBai on scavenging OH and 02 was better than cultivar DaYeOolong, the ability of polysaccharide in Spring on clearing OH and O2 was best. It was also showed that the activity of polysaccharide increased firstly, and then decreased during the process of Oolong tea.. According to the changes of polyphenols, when it was retained about 85%, the content of TPS was high and the activity of TPS was highest, which was regarded the technical index to end shaking during the process of Oolong tea.2. OTPS had immunity effects on diabetes mice. The immuneomodulatory effects of OTPS on STZ-induced Balb/C diabetic mice were measured. It was found that OTPS could significantly intensify DTH caused by DNFB, enhance the activity of NK cell, improve phagocytosis function of peritoneal macrophage and increase the HC50 in serum. Besides, OTPS could raise thymud index and spleen index of diabetes mice. So it can be concluded that OTPS could significantly improve both the cell immune function andhumor immune function in diabetes mice in vivo. The result also showed that with the identical dose the OTPS have better effects on the DM mice than that on the normal mice . In order to verify the nature of immune, the technique of FCM was used to detect the rates of CD. The result s made clear that OTPS could decrease the rate of CD8 T cell and increase the percentage of CD4 T cell and the ratio of CD4/CD8in serum of diabetes rats. Meanwhile, OTPS could also inhibit over expressive NK cells and reduce the rate of activated T lymphous cells. Collectively, these data proved the fact that OTPS could correct the imbalance of immune regulation in diabetic rat in vivo.