The Research Of Opuntia Stricta Polysaccharide Extraction And Its Hypoglycemia Activity

Opuntia stricta, which is perennial and dicotyledon plant, widely distributes on the earth. The resource of Opuntia stricta is rich. In china, Opuntia stricta mainly grows in Sichuan, Yunan, Guizhou, Guangzhou and Hainan province. Nowadays, O.dillenii, O.monaecantha and O.ficus-indica are common medicinal species of Opuntia stricta. The earlier research reported that Opuntia stricta presents anti-tumor activity, anti-inflammatory activity, antidant activity and anti-diabetic activity, and polysaccharide is one of the active components. But there is few report about the hypoglycemic mechanism. In the research, we studied the anti-diabetic activity and hypoglycemic mechanism of crude polysaccharide of Opuntia stricta.Alloxan was selected to induce the diabetic animals. After the mice were fed for 3 days to make them adapt for the experimental environment, a dose of 150mg/kg body weight of alloxan were intraperitoneally injected to the mice.3 hours after injection, the mice was treated with sugar water in order to increase the success rate of induction and decrease the death rate of mice, then, the blood glucose levels were tested by blood glucose test kit. We chose the mice whose glucose level was higher than 11.1mmol/L as alloxan-induced diabetic mice model for the further experiment.In our research, crude polysaccharide of Opuntia stricta greated lowered the blood glucose level of mice by 65.2% compared with the negative control group. And, the crude polysaccharide of Opuntia stricta did not exhibit any obvious hypoglycemic effect on healthy animals(P>0.05), which means the crude polysaccharide of Opuntia stricta has no unfavourable influence on normal blood glucose level.The water-extraction conditions for the crude polysaccharide of Opuntia stricta were optimizated by the response surface method. The optimum extraction conditions were as follows:extraction temperature is 97.9℃; liquid to solid ratio is 8.4:1 (mL·g-1); extraction time is 2.1h. The yield rate of crude polysaccharide of Opuntia stricta was 0.47%. The activities of crude polysaccharide of Opuntia stricta were studied on alloxan-induced diabetic mice. The results show that the crude polysacharide of Opuntia stricta presents obvious therapeutic and preventive effects against diabetes in mice. Furthermore, SOD activity,GSH-Px activity,MDA level,TG level,TCHO level,LDL-C level,HDL-C level and BUN level of mice were measured by test kits, which showed that the crude polysaccharide of Opuntia stricta presents a good activity of anti-oxidation and serum lipid lower.We also tested the toxicity of the crude polysaccharide of Opuntia stricta in mice,including the acute toxicity and sub-acute toxicity and special toxicity experiments. The crude polysaccharide of Opuntia stricta were proved to be safe. No toxic and side effects were found in our toxicity tests.In conclusion, the crude polysaccharide of Opuntia stricta has a higher therapeutic and preventive effects against diabetes and has no toxic and side effects, which would be a potential drug to treat the diabetes in the future.