| Title | A series of cinnamic acid derivatives and their inhibitory activity on intestinal alpha-glucosidase. | | Author(s) | Adisakwattana S, Chantarasinlapin P, Thammarat H, Yibchok-Anun S | | Institution | The Medical Food Research and Development Center, Department of Transfusion Medicine, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand. | | Source | J Enzyme Inhib Med Chem 2009 Oct; 24(5):1194-200. | | Abstract | Inhibition of alpha-glucosidase and alpha-amylase delays the digestion of starch and disaccharides to absorbable monosaccharides, resulting in a reduction of postprandial hyperglycemia. Finding effective mammalian alpha-glucosidase inhibitors from natural sources can be beneficial in the prevention and treatment of diabetes mellitus. We investigated the inhibitory activity of cinnamic acid derivatives against rat intestinal alpha-glucosidase and porcine pancreatic alpha-amylase in vitro. Among 11 cinnamic acid derivatives, caffeic acid, ferulic acid, and isoferulic acid were the most potent inhibitors against intestinal maltase with IC(50) values of 0.74 +/- 0.01, 0.79 +/- 0.04, and 0.76 +/- 0.03 mM, respectively, whereas ferulic acid (IC(50) = 0.45 +/- 0.01 mM) and isoferulic acid (IC(50) = 0.45 +/- 0.01 mM) were effective intestinal sucrase inhibitors. However, all cinnamic acid derivatives were found to be inactive in pancreatic alpha-amylase inhibition. Kinetic analysis revealed that intestinal maltase was inhibited by caffeic acid, ferulic acid, and isoferulic acid in a mixed-inhibition manner. In addition, ferulic acid and isoferulic acid inhibited intestinal sucrase in a mixed type manner, whereas caffeic acid was a non-competitive inhibitor. The combination of isoferulic acid and acarbose showed an additive inhibition on intestinal sucrase. This study could provide a new insight into naturally occurring intestinal alpha-glucosidase inhibitors that could be useful for treatment of diabetes and its complications. | | Language | eng | | Pub Type(s) | Journal Article
| | PubMed ID | 19772492 |
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