Research On Extracting And Separation Of Walnut Proten Peptide And Functional Prosperities

There are quite high nutrition and medicine values in walnut and it is the favaroble material of health food.In recent years, walnut's production was quickly increasing, bringing favaroble opportunities to walnut's deep-processing.To know walnut's nutrition and health care function sciencly, using walnul as material , walnut protein was enzyme hydrolyzed by papain and Alcalase,mainly researching on some hydrolytic properties,the antioxidant functional properties and ACE inhibitory ratio in vitro of hydrolysates. papain and Alcalase hydrolysates were separated. The main results are as follows:For hydrolysates, with time's extension, the content of amino nitrogen, the degree of solubility, the degree of hydrolysis, and peptides content were all increased, the average length of peptides chains were decreased gradually, the scavenging ability of free radical and the ability of deoxidization were also increased. By compareing, papain protease was the optimum protease.Antioxidative activity of hydrolysates, which come from walnut protein by the Papain enzyme was studied.yied of antioxidative Activity of hydrolysates of different hydrolysis time and the different groupof molecular weight of peptides were studied.[Result] in the optimum reaction conditions of enzyme : dosage of enzyme 6000U/g,substrate concentration3% ,pH 8.5,temperature 55℃with 210 min reaction time ,the yied of hydrolysates have strong anti-oxidized ability: 55.43% of scavenging rate of OH·, 64.23% of scavenging rate of O₂^-·, 79.32% of scavenging rate of DPPH·, 98.74% OD/ml of total anti-oxidized ability. the different group of molecular weight of peptides was also studied and the result show that 1321～607Da have strong anti-oxidized ability: 42.26% of scavenging rate of OH·, 57.33% of scavenging rate of O₂^-·, 74.43% of scavenging rate of DPPH·, 88.43 OD/ml of total anti-oxidized ability. hydrolysates with the optimum hydrolysis time of 210 min and 1321～607Da molecular weight of peptides have strong ability of antioxidative activity .Antioxidative activity of hydrolysates ,which come from walnut protein by the Alclase enzyme was studied. yied of antioxidative Activity of hydrolysates of different hydrolysis time and the different groupof molecular weight of peptides were studied.in the optimum reaction conditions of enzyme : dosage of enzyme 3000U/g, substrate concentration 4%,pH 8.5,temperature 50℃with 210 min reaction time ,the yied of hydrolysates have strong anti-oxidized ability: 72.3% of scavenging rate of OH·, 83.1% of scavenging rate of O2-, 102.6% of scavenging rate of DPPH·, 162.986OD/ml of total anti-oxidized ability. the different groupof molecular weight of peptides was also studied and the result show that 1321～607Da have strong anti-oxidized ability: 70.23% of scavenging rate of OH·, 62.57% of scavenging rate of O2-, 99.56% of scavenging rate of DPPH·, 118.987 OD/ml of total anti-oxidized ability. hydrolysates with the optimum hydrolysis time of 210 min and 1321～607Da molecular weight of peptides have strong ability of antioxidative activity .We did orthogonal trial with the ACE inhibitory ratio. The hydrolysate by Papain enzyme with the ACE inhibitory ratio, was gained under the condition of temperature 50℃, pH 7.5, enzymatic hydrolysis time 240min, substrate and substrate concentration 3.0%. Trough separateing by SephadexG-25, the fraction 612-307Da with the higher activity were collected, with the ACE inhibitory ratio being 93.56% . We did orthogonal trial with the ACE The hydrolysate by Alclase enzyme with the ACE inhibitory ratio, was gained under the condition of temperature 40℃, pH 8.5, enzymatic hydrolysis time 150min, substrate and substrate concentration 3.0%. Trough separateing by SephadexG-25, the fraction 1321-612Da with the higher activity were collected, with the ACE inhibitory ratio being 93.27% .