Research On α-Glucosidase Inhibiting Product From Ruditapes Philippinarum

In this research, Ruditapes philippinarum was studied from hydrolysis conditions optimization, immobilized enzyme preparation, active peptides purification and microcapsule preparation, respectively. The main study results as follows:1、The α-glucosidase inhibiting peptides were prepared from Ruditapes Philippinarum. The hydrolysis conditions were optimized by single factor and orthogonal experiments, according to α-glucosidase inhibiting activities. The results showed that the optimum conditions of enzymatic hydrolysis were solid-liquid ratio(m/v)1:30, 2.0% of Pepsin, hydrolysis time 180 min, temperature 32℃ and p H 2.0.On the condition, the degree of hydrolysis was 17.4% and the inhibition rate of products on α-glucosidase was 50.2% at 50mg/m L.2、The immobilized enzyme was prepared with the alginate and chitosan to crosslink. The immobilized enzyme preparation conditions were optimized by single factor experiment and response surface methodology, according to immobilized enzyme activity. The results showed that the optimal immobilization conditions were: the alginate concentration 0.9%, dilution fold of the free enzyme 10-fold, Ca Cl2 3.6%, immobilization time 4h, respectively. On the condition, the recovery of the immobilized enzyme could reach 73.42%. The inhibition rate of products on α-glucosidase was 54.07% by using immobilized pepsin.3. According to α-glucosidase inhibiting rate, DEAE-F.F and Sephadex G-25 were used to isolate and purify the active peptides from the hydrolysate, the component G with higher inhibition rate on α-glucosidase was isolated out, which molecular weight was about 580 Da.4. Alginate-chitosan microcapsules containing α-glucosidase inhibiting peptides(GIP) from Ruditapes philippinarum were prepared. The optimal conditions were alginate concentration1.0%, alginate/GIP ratio1:5, Ca Cl2 concentration5% and chitosan concentration2.0%, which were obtained through single factor tests and orthogonal experiments. Under the conditions, the encapsulation efficiency was 67.21% and the drug-loading percentage was 33.67%. The release efficiency of microcapsules was good in simulated intestinal fluid. Accordingly,the microcapsules prepared in this paper are acid resistant and therefore can be given orally.