[Trypsin inhibitor from buckwheat seeds].

It has been demonstrated that buckwheat seeds contain a proteinaceous inhibitor of trypsin and chymotrypsin. The isolation technique consisted in extraction of the seed flour with water, ammonium sulfate fractionation, isoelectric precipitation, gel filtration on Sephadex G-75 and ion-exchange chromatography on DEAE-Sephadex. The isolated inhibitor is homogeneous according to acidic and basic polyacrylamide gel electrophoresis data. The molecular weight of the inhibitors is about 10 000 as determined by gel filtration on Sephadex G-50; the isoelectric point pI is 5,8; the sedimentation coefficient is 1S. The inhibitor effectively inhibits trypsin, much worse--chymotrypsin and has no effect at buckwheat seed protease, hydrolyzing N alpha-benzoyl-D,L-arginine-p-nitranilide (BAPAase).