小麦面筋蛋白功能短肽的阿片活性及其相对分子质量分布的研究

Opioid Activity and Molecular Weight Distribution of Wheat Gluten Oligopeptides

采用豚鼠回肠离体检定法对由不同蛋白酶(碱性蛋白酶、胰蛋白酶、胃酶、胰酶、中性蛋白酶和复合蛋白酶)水解制备的小麦面筋蛋白短肽的阿片活性进行了测定,结果表明,由碱性蛋白酶、胃酶、胃酶和胰酶复合水解制备的三种面筋蛋白短肽(AWGH、PWGH和PPWGH)具有较好的阿片活性,其IC50值分别为(1.21±0.25)、(1.29±0.38)、(1.57±0.21)mg/mL。采用高效液相色谱对AWGH、PWGH和PPWGH的相对分子质量分布研究发现,其相对分子质量在2000Da以下的组分占多数,并且AWGH中肽组分的分子量较PPWGH和PeWGH要更小一些。采用SephadexG-25对AWGH和PPWGH进行了初步分离,AWGH可以得到三个峰,而PPWGH可以得到五个峰。

Wheat gluten oligopeptides were prepared by hydrolyzing wheat gluten with several commercially available proteases （ Alcalase 2.4L, Pancreatin Trypsin 6.0S, Pepsin, Pancreatin, Neutrase, and Protamex）. The opioid activity of the wheat gluten oligopeptides was determined using guinea pig ileum assay. Result shows that the wheat gluten peptides, AWGH, PWGH, PPWGH, obtained with alcalase 2.4L, pepsin, pepsin, and pancreatin, possess relatively higher opioid activity, with IC50 value （ 1.21 ± 0.25 ）, （ 1.29 ± 0.38 ）, （ 1.57 ± 0.21 ） mg/mL respectively. The molecular weight （MW） distributions of AWGH, PWGH, and PPWGH were determined by size exclusion HPLC. Result shows that most peptides possess MW lower than 2000Da and AWGH possesses smaller peptides compared with PWGH and PPWGH. Additionally, AWGH and PPWGH were separated on Sephadex G-25. There occurred 3 peaks for AWGH and 5 peaks for PPWGH.