Angiotensin I-Converting Enzyme Inhibitory Activity of the ${\kappa}-Casein$ Fragments Hydrolysated by Chymosin, Pepsin, and Trypsin

${\kappa}-Casein$의 Chymosin, Pepsin 및 Trypsin 가수분해물에 대한 안지오텐신 변환효소 저해효과의 탐색

The isolated ${\kappa}-Casein$ on gel permeation chromatography was hydrolyzed by chymosin, trypsin, and pepsin. The 3% TCA soluble portion of the hydrolysates were dialyzed on the angiotensin-I converting enzyme (ACE) inhibition rate (%,) and inhibitory activity $(IC_{50})$ were determined. The trypsin hydrolysate exhibited the highest ACE inhibition rate while the chymosin hydrolysation showed the lowest activity. The hydrolysate was dialyzed using dialysis membrane with various molecular cut-offs, and $IC_{50}$ was determined. As the pore size of the dialysis tubing increased, the ACE inhibitory activity decreased.

산 casein으로부터 FPLC를 이용하여 gel permeation column으로 ${\kappa}-Casein$을 분획한 다음, 이를 chymosin, pepsin, trypsin 으로 각각 처리하여 3% TCA에서 soluble한 부분을 증류수로 투석(MW cut-off 1kDa)시킨 후 ACE저해 효과를 측정한 결과, trypsin으로 분해 시킨 경우 ACE 저해율이 94.7%로 가장 높게 나타났으며, chymosin 가수분해물은 가장 낮았다. GMP를 투석막의 종류에 따라 투석 시킨 후 $IC_{50}$을 측정한 결과, MW cut-off 의 크기가 증가할수록 ACE저해효과는 감소하는 것으로 나타났으며, MW cut-off 2 kDa의 경우가 가장 높은 저해율을 보였고 MW cut-off 5kDa에서는 저해율이 가장 낮았다.