title: Several properties of the partially purified proteinase inhibitor in eggplant exocarp.
abstract: A proteinase inhibitor was isolated and partially purified from the exocarp of eggplant, Solanum melongena L., by means of acetate buffer extraction, heat treatment, salting-out and column chromatography on DEAE-cellulose. This preparation showed inhibitory activities on various proteinases; trypsin [EC 3.4.4.4] and Pronase were strongly inhibited while alpha-chymotrypsin [EC 3.4.4.5] and Nagarse were weakly inhibited. The inhibitor was a protein substance, and, therefore, it was gradually inactivated by the long-time incubation with Pronase. The inhibition mode was non-competitive on trypsin and competitive on Pronase on the basis of Lineweaver-Burk plots. The investigations on the inhibition behavior in the co-existence of two kinds of proteinases suggested that the inhibitor was not of multi-headed type.
mesh_terms: D002918:Chymotrypsin / Q000037:antagonists & inhibitors; D004791:Enzyme Inhibitors / Q000302:isolation & purification / Q000494:pharmacology; D010944:Plants / Q000032:analysis; D011402:Pronase / Q000037:antagonists & inhibitors; D011480:Protease Inhibitors; D013329:Structure-Activity Relationship; D013381:Subtilisins / Q000037:antagonists & inhibitors; D014361:Trypsin Inhibitors / Q000302:isolation & purification / Q000494:pharmacology; D014675:Vegetables / Q000032:analysis
chemical_list: D004791:Enzyme Inhibitors; D011480:Protease Inhibitors; D014361:Trypsin Inhibitors; D013381:Subtilisins; D002918:Chymotrypsin; D011402:Pronase