The Preparation And Function Of Antioxidative Peptides And Antitumor Peptides From Korean Pine Nuts

Pinus koraiensis Sieb. et Zuee is a rare tree species of Xiao xing an ling in China. The pine nut is a sort of fruit with high nutritional value and rich in protein, which is a good protein source to make functional active peptides. In this paper, the hydrolysis process, anti-oxidant activity, anti-tumor activity, purification and structure of peptides from pinus were investigated.Protease hydrolysis method was used to prepare the pine nuts antioxidant peptide. With the reducing ability as index, enzymatic hydrolysis craft was optimized by response surface method and the optimum enzymatic hydrolysis condition for pine nuts antioxidant peptide was that pH 8.5, enzyme-substrate ratio 6250U/g protein, 0.6% substrate concentration, reaction temperature 51℃, hydrolysis time 120min. In this hydrolysis condition, the pinus hydrolysis of total antioxidant peptide A700 0.652 to reproduction. In addition, the reducing ability and hydroxyl, superoxide radical-scavenging activity and ABTS. scavenging activity of pinus peptides were observed. As a result, with a concentration of 20 mg/mL, the reducing ability of peptides was 84.3% that of vitamin C; hydroxyl, superoxide radical-scavenging activity and ABTS. scavenging activity were 96.91% , 58.59% and 100%, respectively. The radiation damage model was established to study the in vivo antioxidant. As the results showed, pinus antioxidant peptides has no significance on the body weight of mice and can increase the spleen index and liver index, especially vitality of the superoxide dismutase(SOD) and glutathione peroxidase (GSH-PX) significantly, and reduce the vitality of nitric oxide snythase(NOS) and huang purine oxidase(XOD) as well as the content of peroxidant product—malondialehyde(MDA).Protease hydrolysis method was used to pine nuts anticancer peptide. With the hydrolysis degree as index, enzymatic hydrolysis craft was optimized by response surface method and the optimum enzymatic hydrolysis condition for pine nuts anticancer peptide was that pH 9.0, enzyme-substrate ratio 6000U/g protein, 0.6% substrate concentration, reaction temperature 55℃. In this condition, peptides which the DH% was 50% have the strongest antitumor effect. MTT assay was applied to determine the effect of pinus peptides in vitro anti-tumor activity. Result showed that pinus peptides can restain cancer cell proliferation and has anti-cancer function. Pinus peptides after training 48h with HT29 and HepG2 tumor cell ,measured IC50 were 0.457mg/mL, 0.825mg/mL, respectively.With Sephadex G-50 and G-25 as the loading material, Gel filtration chromatography(GFC) was used to elute and separate the pinus antioxidant peptides and the pinus anti-tumor peptides, the strongest antioxidant activity components named PAⅢ-c and the strongest anticancer activity components named PCⅡ-c were obtained . The molecule weights distribution was determined by HPGPC, the molecular weight of PAⅢ-c was about 300~1000Da and the molecular weight of PCⅡ-c was about 250~500Da. The compositions of PAⅢ-c component and PCⅡ-c component amino acid were measured by amino acids automatic analyzer, and as the resuly shown, hydrophobic aminoacids content of antioxidant peptides PAⅢ-c component is higher, accounting for 30% of the total amino acids, which is the main reason of its antioxidant function.