Study On The Antioxidant Activity Of Walnut Polypeptide

Purpose: A study of extraction and isolation from walnut walnut protein, to optimize theprocess, to the protein purification, finally the purified protein oxidation, opens the way forwalnut protein synthesis.Method:Rough machining of walnut, alkali solution and crude protein samples obtainedby acid precipitation, after washing, neutralization, drying, protein separation steps separatedfrom walnut protein quality, optimized to obtain the best process on extraction process; theprotein quality by lyophilization was refined, by optimizing the selection of enzyme, process,preparation the exact biological function of hydrolysates, and in-depth study of antioxidantpeptides which, the development of walnut protein functional foods with antioxidant activity(Health) provides theoretical guidance.Result: The optimum extraction conditions of walnut protein of walnut for degreasingwith petroleum ether at room3, control the ratio of solid to liquid1:6, each skim1H, solidventilation cabinet drying volatile,45degree oven drying. Dry powder sieving and water ratioof1:15modulation by0.5mol/L Naoh PH9.0uniform, heated1H45degree oven, samplingcentrifugal4000rpm10Minn. The supernatant by0.5mol/L Hcl PH4.81H precipitation,centrifugal separation, precipitation, and precipitation of freeze-dried.The walnut protein purification to obtain refined walnut protein, then after hydrolysisenzymes of walnut protein hydrolysates, we will walnut protein hydrolysates do DPPHclearance test; hydroxyl radical scavenging assay; superoxide anion scavenging test, test thereducing ability, chelating metal ion, the linoleic acid oxidation test, tests show, walnuthydrolysates were with DPPH scavenging activity, hydroxyl radical scavenging, superoxideanion scavenging ability, reducing power, chelating capacity, antioxidant capacity. Finally,after struggling to purification test, high performance liquid chromatography and massspectrometry, we get a sequence of the hydrolysate protease.Conclusion: F2-5lyophilized samples were dissolved in water, the first phase todetermine the purity of the liquid, liquid phase diagram shows only one peak, so it is pure; the liquid sequence identification using professional software.MS/MS of Peaks de novofunctional analysis, confirm the results and manual calculation, the amino acid sequenceshown in.F2-5the Ala-Gly-Gly-Ala. Chen (1996), Chen (2011) and Sampath Kumar (2011)pointed out that the hydrophobic amino acid peptide in favor of increased lipid solubility,oxidation inhibiting lipid; side chain of glycine in only one hydrogen atom, the polypeptidebackbone has high flexibility, increase the antioxidant ability of polypeptide, the activepeptide in this paper also have antioxidant activity...