标题：An α-Amylase Inhibitor from Cranberry Bean (Phaseolus vulgaris): Its Specificity in Inhibition of Mammalian Pancreatic α-Amylases and Formation of a Complex with the Porcine Enzyme
期刊名称：Journal of Nutritional Science and Vitaminology
印刷版ISSN：0301-4800
电子版ISSN：1881-7742
出版年度：1987
卷号：33
期号：5
页码：359-367
DOI：10.3177/jnsv.33.359
出版社：Center for Academic Publications Japan
摘要：A proteinaceous inhibitor that inhibits mammalian α-amylases was prepared from cranberry bean and examined for its reactivity with α-amylases from various origins. The cranberry bean α-amylase inhibitor (CBAI) exhibited inhibitory effects on pancreatic α-amylases from the following mammals: pig, dog, cat, horse, sheep, cow, rabbit, guinea pig, rat, and mouse. CBAI showed a maximal inhibition at pH 5.5 against porcine pancreatic α-amylase (PPA). It was confirmed by gel filtration that a complex was formed in the 1:1 ratio between CBAI and PPA when they were incubated at 37°C for 30 min at pH 5.5. A similar inhibition pattern was also observed at pH 6.9 that is optimal for the amylase reaction, but much higher concentrations of CBAI were required to give 50% inhibition at pH 6:9 than at pH 5.5. Especially, both bovine and rat α-amylases were virtually unreactive to CBAI at pH 6.9.
关键词：formation of complex;species-specificity;α-amylase inhibitor;pancreatic α-amylase;cranberry bean
