Trypsin inhibitor from starchy endosperm of rye seeds

Abstract

A method for the preparation of a trypsin inhibitor from starchy endosperm of rye seeds is described. Isolation and purification comprised the following steps: salting out of the water-soluble proteins at pH 4.5 with ammonium sulphate (0.4 saturation), followed by chromatography on CM-Cellulose, Sephadex G-100 and SE Sephadex C-25. The finally purified preparation of inhibitor was found to be homogeneous by both chromatographic and electrophoretic analyses. The preparation inhibited trypsin and chymotrypsin but was inactive against papain, kallikrein and pepsin. The molecular weight of the inhibitor was calculated to foe about 10 000.