Study On The Enzymatic Hydrolysis Preparation And Anti-fatigue And Anti-oxidant Activity Of Soybean Peptides

Oxidative stress that occurred in exercise is an essential cause of fatigue. The antioxidants can alleviate the oxidative stress and lessen fatigue. The soybean peptide is a kind of good exotic antioxidant which has features such as simple-craft, low-cost, and fast absorbed .This experiment investigated the anti-fatigue and anti-oxidation effects of soybean peptide in mice, and the relation between them.At first, we chose the craft of soy protein enzymolysis. The effects of 4 kinds of proteases (the alkalinity proteinase, the neutral proteinase, Neutrase, papain) on the hydrolysis of soy protein were compared by the degree of hydrolysis and the ability of eliminating free radical. The hydrolysate of alkalinity proteinase and neutral proteinase had the highest ability of eliminating free radical. Double-enzyme hydrolysises were carried on with this two kinds of proteases, and the products were named soybean peptide A & B.In first test,40 mice were randomly divided into control group, soypeptide A&B group, soy protein group which were given respectively with physiological saline, soypeptide A & B and soy protein i.g. at 0.8g/d·kg. After 2 weeks, weight-loaded swimming test was performed to observe the death time and the other biochemical indicators, such as the activities of LDH and SOD, the content of hepatic glycogen and BUN. The exhausted time of soypeptide B group was obviously longer than the other groups; the activity of LDH in soypeptide B group was obviously lower than the other groups; soy peptide B increased the content of hepatic glycogen, and decreased the level of BUN; the activity of SOD in group B was the highest. It is clear that soy peptide B which is smaller in molecular weight increased the abilities of anti-fatigue and anti-oxidation of mice, and the anti-fatigue and anti-oxidation activity of soy oligopeptides are obviously related.In second test, 50 mice were randomly and equally divided into control group, soypeptide A&B group, soy protein group, and velvet blood peptide which were given respectively with physiological saline, soypeptide A&B and soy protein i.g. at 0.5g/d·kg. After 3 weeks, Morris water maze test and despair swimmig test were performed to observe the success ratio and despair time. The results were that the soybean peptide B group had the shortest despair time, the hightest content of hepatic glycogen and the activity of SOD. Soybean peptide B can alleviate mental fatigue and decrease the level of BUN. The anti-fatigue activity of soybean peptide A was a little lower than peptide B, so did velvet blood peptide. Activated charcoal adsorption and the organic acid, the glucose were used together to cover up the bitter taste. The best proportion is: 2% activated charcoal, 0.3% citric,0.1% malic, and 3% glucose. Bitter taste is covered basically and the solution has the fragrance of apple.