Study On Functional Activities Of Oyster Peptide

Oyster is a kind of rich aquatic products of huge economic value in China.The meat is delicious and nutrition is rich.It has very high edible and medicine value.So far scientists had extracted polysaccharide?polypeptite and other bioactive substances from Oyster.In this paper,we used Crassostrea angulata as raw matrial to prepare oyster peptide by compound enzymatic technics.Studied the antifatigue?antioxidant and hypoglycemic activity of oyster peptide in mice by animal experiment.The results of Anti-fatigue activity by animal experiment proved that the exhausted swimming time of normal group was 9.5 min,low?0.5 g/kg·BW·Oyster peptide??middle?1.0g/kg·BW Oyster peptide?and high group?2.0 g/kg·BW Oyster peptide?were 15.82 min?16.02min?16.73 min,increased by 66.5%?68.8%and 76.1%than normal group?p<0.01?.After swimming,the content of BUN was 7.7 mmol/L,higher than other groups?p<0.05?.Liver glycogen was 11.88 mg/g,lower than low?middle and higher group obviously?p<0.01?.Lactic acid increased after swimming,oyster peptide could restrain and clear lactic acid obviously?p<0.05?.The clearance rate of high dose could reach 44.49%.Results showed high-dose group improve anti-fatigue activity very significantly?p<0.01?in mice.Anti-oxidant in vitro showed:ability to clear the·OH radical and DPPH radical of oyster peptide was well.The clearance rate of·OH and DPPH·reached 90%.When concentration reach0.08 mg/mL,IC₅₀0 was 0.04 mg/mL.Anti-oxidant in vivo showed that oyster peptide to increase antioxidant capacity had very significant effect?p<0.01?.It reduced the content of MDA significantly?p<0.01?,high group was only 8.74 mmol/L,lower than 10.49mmol/L of normal group.Compared with model control group,the oyster can significantly increased the SOD activity?p<0.01?,high dose group activity can be increased by 36%.The GSH content of high dose group was 12.79 mg/g,increased by 33.79%by model,had a very significant role in increasing GSH?p<0.01?.Oyster peptide had a good function to inhibit protein carbonyl content,low dose group alone has a significant effect?p<0.01?.Animal experiment results showed that each dose group of oyster peptide to increase antioxidant capacity had very significant effect in mice?p<0.01?.Hypoglycemic experiment indicated that their was no effects of oyster peptide on the blood sugar levels for the normal mice.Oyster peptide groups had a good mental state and blood sugar decreased gradually.Middle and high dose groups'blood glucose dropped to 17.86 mmol/L and16.24 mmol/L respectively,closed to 14.46 mmol/L of the positive control group,has significant effect?p<0.05?.