Preparation of carboxymethylated polysaccharides from mycelia of Catathelasma ventricosum and their antidiabetic properties

Theahoroacetic acid method under the alkaline condition is adopted to conduct carboxymethylation modification of catathelasmaventricosum polysaccharides ( CVPs) to obtain carboxymethylationcatathelasmaventricosumpolysaccharides (cCVPs). In order to improve the acquiring rate ( A) and degree of substitution of cCVPs, the synthetic process has been optimized. The optimal condition is: the concentration of NaOH is 20%; the dosage of monochloro acetic acid is 3g; the isopropanol is 15ml; the reaction temperature is 65 degrees C; the response time is 4h; the molecular weight is 5.0x103-1.0x104 Da. The final A and DS of cCVPs obtained reach 82.01% and 0.891, respectively. Besides, the regulating level of cCVPs of the oxidative stress level within the body of mice suffering from diabetes is also studied. Experimental results suggest that carboxymethylation can significantly improve the antioxidant activity of the CVPs.