Evaluation of alpha-glucosidase inhibition by using an immobilized assay system.
Evaluation of alpha-glucosidase inhibition by using an immobilized assay system.
复制标题
使用固定化测定系统评估α-葡萄糖苷酶抑制作用。
DOI：
10.1248/bpb.23.1084
复制
发表时间：
2000
影响因子：
2
通讯作者：
Kiyoshi Matsumoto
中科院分区：
文献类型：
--
作者：
T. Oki;T. Matsui;Kiyoshi Matsumoto
用溴化氰活化的Sepharose4B固定化载体评价了天然和合成抑制剂对肠膜结合水解酶α-葡萄糖苷酶(AGH)的抑制作用。合成抑制剂(阿卡波糖和伏格列波糖)对固定化AGH(IAGH)的抑制作用与游离AGH(FAGH)的抑制程度不同：阿卡波糖在iAGH-麦芽糖酶测定体系中的IC50值为340-430 nM，fAGH为11 nM。不同官能团(COOH、OH、CH3和NH2)的封闭试剂对iAGH-麦芽糖酶的抑制作用不同。另一方面，只有当使用0.1Mβ-丙氨酸诱导的带负电荷的载体时，才能观察到显著的iAGH-蔗糖酶抑制活性。用iAGH测定系统测得的Km值与用fAGH法测得的Km值相近。在天然抑制剂作用下，D-木糖体内葡萄糖抑制的iAGH-蔗糖酶抑制活性是fAGH的两倍。绿茶提取物对两种AGH检测系统的抑制作用几乎相同。
The inhibitory effects of natural and synthetic inhibitors on the intestinal membrane-bound hydrolase, alpha-glucosidase (AGH), were evaluated by using an immobilized cyanogen bromide-activated Sepharose 4B support. Immobilized AGH (iAGH) inhibition study by synthetic inhibitors (acarbose and voglibose) revealed that the magnitude of inhibition differed from that in the free AGH (fAGH) study: IC50 value of acarbose in iAGH-maltase assay system, 340-430 nM; fAGH, 11 nM. iAGH-maltase inhibition by both inhibitors was influenced by blocking reagents with different functional groups (COOH, OH, CH3, and NH2 groups). On the other hand, significant iAGH-sucrase inhibitory activity was observed only when using the negatively charged support induced by 0.1 M beta-alanine. The Km values obtained in the iAGH assay system were similar to those from the fAGH method. With natural inhibitors, the iAGH-sucrase inhibitory activity of D-Xylose, with in vivo glucose suppression, increased twice compared to that in fAGH. Green tea extract gave almost the same inhibition for both AGH assay systems.