Antioxidant and Hypoglycemic Activity of Polysaccharide from Tea

  • Yu, Zhi (Huazhong Agricultural University, Key Lab of Horticultural Plant Biology of Ministry of Education) ;
  • Zhang, Yun (Huazhong Agricultural University, Key Lab of Horticultural Plant Biology of Ministry of Education) ;
  • Ni, De-Jiang (Huazhong Agricultural University, Key Lab of Horticultural Plant Biology of Ministry of Education)
  • Published : 2006.12.30


Tea polysaccharide had high antioxidant activity and it could be used to cure diabetes. Antioxidant activity of tea poly-saccharide (TPS) from three kinds of tea (green tea, oolong tea and black tea) were compared, the result indicated that oolong tea polysaccharide (OTPS) had the highest antioxidant activity. In order to explicate the mechanism of antioxidant and hypoglycemic activity, the streptozotocin (STZ)-induced diabetes mice model (DM) was established. The influence of OTPS on blood-glucose, content of MDA and NO, and activities of GSH-PX, SOD, NOS in serum, kidney and liver were investigated. The result showed that after four weeks injection of OTPS to DM mice, the blood-glucose of three treatment group reduced by 14.5%,21.5% and 33.3%, respectively, comparing to the model control. The reduction effect of OTPS increased with the rise of dose. The activity of SOD and GSH-PX elevated significantly, while the activity of NOS decreased. The content of MDA and NO reduced significantly. The above results imply that antioxidant activity was enhanced. Comparing to XKW treatment, the effect of a dose of 300mg/(kg. bw) OTPS was much better. The research showed that the OTPS had a significant effect on reducing blood glucose, and could enhance the antioxidant activity of DM mice.


  1. Barry H, M.C. John and I.A. Okezie 1987. The deoxyribose method: A simple 'Test-tube' assay for determination of rate constants for reactions of hydroxyl radicals [J].Anal Biochem 1987: 215-219
  2. Beauchamp C. and I. Fridovich. Superoxide dismutase Improved assays and an assay applicable to acrylamide gels [J]. Anal Biochem,1971 44: 276-287
  3. Chen, H. X. and B.J. Xie. 2001. Progress on the pharmacological activities of tea polysaccharides. Journal of Chinese Medicinal Materials 24: 65-67
  4. Haixia Chen, M. Zhang and X. Bijun. 2005. Components and antioxidant activity of polysaccharide conjugate from green tea [J] Food Chemistry 90: 17-21
  5. Isiguki, K.,T. Takakuwa and T. Takeo. 1992. Anti-diabetes mellitus effect ofwater-soluble tea polysaccharide. In Proceedings of international symposium on tea science 1991, Shizuka, Japan: The Organizing Committee of ISTS. pp. 240-241
  6. Li B.Q. and H.L. Zhang. 1996. Extraction of tea polysaccharides from low-grade tea and their hypoglycemic effects [J] Tea science 16(1)
  7. Ni D.J. and Y.Q.Chen. 2003. Condition s and parameters for extraction of tea polysaccharides [J] Transactions of Chinese Society of agricultural Engineering 19(2)
  8. San, T. F. Umeda and T. Hashimoto et 1998. Dative stress measurement by in vivo electron spin resonance spectroscopy in rats with streptozotocin-induced diabetes [J]. Diabetologia, 1998 41(11): 1355-1360
  9. Perry G. RainaA., K. Nonomura A., T.Wataya, L.M. Sayre and M. A. Smith. 2000. How important is oxidative damage. Lessons from Alzheimer's disease. Free Radical Biology and Medicine 28: 831-834
  10. Tadakazu, T., U. Tomoki, K. Hitoshi, Y. Fumihisa and M. Mistugu. 1998. The chemical properties and functional effects of polysaccharides dissolved in green tea infusion. Nippon Shokuhin Kagaku Kogaku Kaishi 45: 270-272
  11. Wang, D. F., J. Li, C.H. Wang, G.W. Zhao, Y. Jin, D. D. Chen and S. Ye. 2000. Study on the component and immune activity of polysaccharides from tea. Journal of Tea Science 20: 45-50
  12. Wang, D. F., C.H. Wang, J. Li and Zhao. 2001. G W. Components and activity of polysaccharides fromcoarse tea. Journal of Agricultural and Food Chemistry 49: 507-510
  13. Zhang W. J. Biochemistry Rresearch Technology of Glycoconjugates [M] Hangzhou: Zhejiang University Publishing House, 1998
  14. Xu S. Y., R. L. Bian and X. Chen. 2002. Experimental methods in Pharmacology, Beijing : People's Medical Publishing House pp. 1523-1526