Determination Of The Contents Of Lunasin In Different Varieties Soybean And Activity Study

Polypeptide Lunasin,a functional peptide was reported in soybean which was rich in protein and polypeptide.In order to determine the content of Lunasin in domestic soybeans,six kinds of domestic soybean were used as experimental materials.SDS-PAGE method was used to purify the Lunasin.After Enzymatic hydrosis,NanoLC-Obitrap and PRM were used to study the content of Lunasin.The content of Lunasin was 4.66 mg/g in Wangdou35,2.24 mg/g in Zhonghuang 13,3.35 m/g in Zhonghuang 75,2.59 mg/g in Xu dou14,2.03 mg/g in Qian Dou 7,and 2.87 mg/g in Heihe 43,et al.Respectively.These results showed that the six kinds of domestic soybean contain abundant Lunasin,and the method used in this study is simple and reproducible,and the data is accurate and have a good linear relationship.The method could be used to determine the content of Lunasin in soybean and to screen the soybean varieties which are rich in Lunasin.In this study,a uric acid model of zebrafish was established,and the uric acid activity of Lunasin was evaluated.Except for 10 μM concentration,p < 0.05,and other concentrations,p > 0.05,suggesting that Lunasin had no effect on zebrafish uric acid under the experimental conditions.The lipid-lowering activity of soybean polypeptide Lunasin was evaluated and studied using zebrafish hyperlipidemia model.A high-fat diet was fed to zebrafish juvenile fish to build a hyperlipidemia model.Blood lipid deposition were assayed for lipid deposition by oil red O staining.The lipid-lowering activity of Lunasin was evaluated using zebrafish tail vascular lipids as an index.RT-PCR was performed.Quantitative detection of multiple genes associated with lipid metabolism and metabolism to analyze the possible mechanism of Lunasin hypolipidemic effect.The mRNA expression of five genes including HMGCR,CYP7A1,LDLR,MTP and FSA in normal zebrafish,high-fat-fed zebrafish,Luasin-immersed zebrafish and soybean extract-treated zebrafish was examined.The experimental results showed that Lunasin may regulate blood lipids mainly by participating in cholesterol metabolism and reduce blood lipid levels by upregulating LDLR receptors on the surface of hepatocytes and downregulating the transcription level of cholesterol-7-hydroxylase(CYP7A1).