Study On Preparation And Anti-alcoholism Activities Of Defatted Walnut Polypeptide

In this paper, the defatted walnut was the raw materials. The polypeptide was obtained after protein extraction and enzymatic hydrolysis. The walnut protein extraction condition and the enzymatic hydrolysis conditions were optimized by orthogonal experiment based on single factor study. And then, acquire different molecular weight polypeptide through ultrafiltration. At last, the better component was selected to detect the anti-alcoholism activities effect by Valle-Hoch method in vitro.(1) The extraction of protein:Based on the study of our team. After the factors screen experiment, orthogonal experiment show that it will greatly improve the extraction yield of walnut protein when the concentration of NaCl was 0.13%, the flashing time was 30s, ultrasonic extraction time was 25 min, the digestion time was 2 h. Protein extraction rate is 89.76%(2) Enzymatic hydrolysis:The enzymatic hydrolysis process was optimized by conducting orthogonal design test. The optimum condition for double-enzymatic hydrolysis of the Almond dregs was that protease amounts of enzyme 4%, temperature 65℃, pH10,Time was 5h. and papain:amounts of enzyme 5.0%, temperature 60℃, pH7.5, Time was 3h. Under such conditions, The final degree of hydrolysis was 43.26%, meanwhile DPPH clearance rate was 90.37%.(3) Ultrafiltration:dual enzymatic hydrolysis of polypeptide dissolved in a certain concentration of buffer, though the molecular weight of 0-5KDa,5KDa- 10KDa,10KDa-30KDa ultrafiltration membrane separation.results revealed that when the enzymatic hydrolysis 5KDa-10KDa molecular weight the alcohol dehydrogenase (ADH) enzymatic activity is best. And through the components of DPPH ultrafiltration clearance rate experiments, we can found that as the same result, the molecular weight peptides in 5KDa-10KDa time, DPPH clearance also was the best. Comparing with the walnut proteins, the experimental results showed that the content of glutamic acid and phenylalanine of this component was significantly higher than the original walnut protein content.(4) Determination of amino acids:through determining the amino acid content of different fragments, found that glutamic acid and alanine slightly in walnuts sober polypeptide fragments is slightly higher than the other peptide fragments, but there was no significant difference. Described amino acid content of the polypeptide fragment is not the decisive factor anti-alcoholism activities effect.