[Influence of food browning on nutrition. III. Effect of brown substances on digestive enzyme activity (author's transl)].
In the present study, we separated and partially purified brown substances from eggplants and examined their inhibitory action on trypsin activity. The following results were obtained: 1. The first half of the elute after passing ethanol-extractable brown substances through DEAE-cellulose column showed no inhibitory action on trypsin, whereas the middle portion of the elute contained a trypsin inhibitor(s). Similar results were obtained after fractionation with Sephadex G-25. The degree of inhibition was increased after purification. 2. Both crude ethanol extracts of eggplant brown substances and acetate buffer extracts from eggplant exocarps showed similarly an enzyme inhibition of competitive type. 3. Both nondialyzable portion of ethanol extracts and purified fraction after Sephadex G-25 passage showed a noncompetitive type of inhibition. DOPA-melanin and chlorogenic acid-melanin as model substances exhibited a similar noncompetitive inhibition. Purified ethanol extracts of eggplant brown substances showed an ultraviolet absorption spectrum similar to that of chlorogenic acid. From these findings it is concluded that both eggplant brown substances and polyphenol substances play an essential role in the inhibition of digestive enzymes.
D008543:Melanins / Q000494:pharmacology; D010860:Pigments, Biological / Q000494:pharmacology*; D010936:Plant Extracts / Q000494:pharmacology; D014357:Trypsin / Q000032:analysis; D014361:Trypsin Inhibitors; D014675:Vegetables / Q000032:analysis*
D008543:Melanins; D010860:Pigments, Biological; D010936:Plant Extracts; D014361:Trypsin Inhibitors; D014357:Trypsin