Study of preparation and purification process of antihypertensive peptides from Yak milk casein

To prepare the antihypertensive peptides,the optimal enzymatic hydrolysis conditions of Trypsin and purification process were studied.The optimal hydrolysis conditions were determined by single factors and orthogonal experiments,and the optimum hydrolysis conditions were temperature 37℃,p H8.0,trypsin added2.5%,with reaction 2.5h,the capacity of angiotensin- converting enzyme inhibition was 85.26%. Hydrolyzates were separated and purified by high performance liquid chromatography( HPLC) and mass spectrometry,and the amino acid sequences were HQGLPQEVLNENLLR,AVPYPQR and TKVIPYVR.