Trypsin inhibitors of fababeans (Vicia fabaL. var. minor). 1. Preliminary studies.

摘要

Trypsin-inhibitor activity (TIA) of three cultivars of fababeans was compared with that of soybean. A 50ensp;mMphosphate buffer, pH 7.6, extract of soybean contained 35 times more specific TIA than similarly prepared extracts of fababeans. The fababean trypsin inhibitors (TI), like those of soybean, were highly thermostable. The crude extract possessed 13 to 20 of the original inhibitor activity after heating in a boiling water bath for 60ensp;min. The total TIA was higher in extracts of phosphate (pH 7.6) and of ammonium formate (pH 3.2) than of acetate (pH 4.6). However, the specific TIA of the lower pH extracts was higher as a result of a reduced solubility of the fababean proteins at these pH values.