The Protein Extracted And Antihypertensive Peptides Preparation From The Kernel Of Juglans Mandshurica Maxim

The kernel of Juglans mandshurica is rich in various nutrients. Protein content is particularly rich except fat. This test used Juglans mandshurica as raw materials, compared the main nutrients and amino acid content of different field (HeiLongJiang, JiLin). Comprehensive comparison the nutrition and the kernel ration, confirmed MuDanJiang and BaiShan samples were more excellent. The amino acid analysis of the samples from MuDanJiang and BaiShan, showed that MuDanJiang sample had higher nutritional value compared with Baishan sample and becomed raw materials for follow-up tests.Protein classification was extracted according to the Osboren method. The results showed that glutelin content is a maximum of79.49%in the total protein, albumin content is5.68%, globulin content is4.67%, finally for prolamin content is0.87%. The above four proteins in SDS-PAGE electrophoresis analysis showed that albumin mainly concentrated in the molecular weight of88kDa,61kDa,41kDa,23kDa four molecular weight area, globulin concentrated in94kDa,59kDa,41kDa,24kDa,20kDa five molecular weight area, prolamin mainly concentrated in101kDa,59kDa,40kDa,27kDa,19kDa five molecular weight area, glutelin mainly concentrated in112kDa,68kDa,44kDa,20kDa four molecular weight area.A method of extracting protein using alkali liquor from the Chinese Northeast walnut (Juglans Mandshurica Maxim) kernel residue degreased by the supercritical CO2was studied. According to a single factor experiment and orthogonal test we get the result:the protein extraction rate maximum was88.05%at the optimal conditions of NaOH concentrations0.02mol/L, materials to liquid ratio1:30, extraction temperature50℃, extraction time1.5h. The isoelectric point of the alkali-soluble protein was4.5.Using papain, neutral proteinase, Alcalase3kinds of protease hydrolyzed2%walnut kernel protein solution, according to the index determined Alcalase was the best choice of the enzyme preparation which btained the hydrolysate from the hydrolysis could inhibit ACE to61.58%. In the single factor analysis, the effects of enzymolysis pH, enzymolysis temperature, enzymolysis time and enzyme addition on the results were measured. The response surface methodology was used to optimize the conditions of enzymolysis. The results showed that the optimum conditions were enzymolysis pH8.2, temperature56℃, time4h and enzyme addition5880U/g substrate. The ACE inhibitory ability of the hydrolysate was72.48%.The antihypertensive peptide was separated by the method of ultrafiltration (intercept molecular weight5000). The ultrafiltration liquid AEC inhibition was88.917%(IC50=1.196mg/ml), improved17.699%comparaed the original peptide liquid. The ultrafiltration liquid freeze-dried was burified by SephadexG-15gel chromatography. There were3 components appered after the gel chromatography. The ACE inhibition ratio of the second peak component (IC50=0.474mg/ml) was62.235%higher than the two others.Used purified peptide in cell test, observed the human umbilical vein endothelial cells culture, and determined cells release NO, ET content to prove the function of antihypertensive peptides made from Chinese Northeast walnut protein. The results indicated that the ACEIP at certain concentration range had an antihypertensive effect similar with the blood pressure drugs (Captopril). ACEIP can promote human umbilical vein endothelial cells release NO, and reduce ET release.