Cereal Chem 58:211 - 213.  |  VIEW ARTICLE
Characterization and Heat Stability of Trypsin Inhibitors from Rye, Triticale, and Wheat Samples.

C.-R. Chang and C. C. Tsen. Copyright 1981 by the American Association of Cereal Chemists, Inc. 

Extinction coefficients were determined for the trypsin inhibitors (TI) isolated from rye, triticale, hard red winter wheat, and durum wheat. Except for TI from hard red winter wheat II, all the inhibitors contained carbohydrate. No free sulfhydryl group was detected in any of the inhibitors by the amperometric titration method. Amino acid composition studies on triticale and rye TI indicated the similarity of their amino acid constituents, ie, a high amount of glutamic acid, leucine, and glycine and very little methionine and tryptophan. All inhibitors were heat stable. Triticale TI was the most heat resistant among the inhibitors tested. Heating at 100 C for 1 hr inactivated only 7% of triticale TI. Heating up to 80 C caused minimal conformational perturbation of the inhibitors, and the perturbed molecules tended to go back to their original conformation upon cooling. However, heating at 125 C altered the conformation of the inhibitors and permanently inactivated all of them.