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a -Glucosidase Inhibitors from Dendrobium tortile

Rachawadee Limpanit, Taksina Chuanasa, Kittisak Likhitwitayawuid, Vichien Jongbunprasert and Boonchoo Sritularak

Department of Pharmacognosy and Pharmaceutical Botany, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok 10330, Thailand

Abstract: From the whole plant of Dendrobium tortile, a new compound, namely 4-(2-hydroxypropyl)-2(5H)-furanone, was isolated, together with six known compounds, which included trans-tetracosylferulate (2), cis-docosylferulate (3), p-hydroxybenzaldehyde (4), 3,4-dihydroxy-3,4 ¢ -dimethoxybibenzyl (5), (2S)-eriodictyol (6) and dendrofalconerol A (7). The structures of these compounds were determined through analysis of 1-D and 2-D NMR and HR-ESI-MS data. All of the isolates were evaluated for their a -glucosidase inhibitory activity. Compound 7 showed strong a -glucosidase inhibitory activity when compared with the positive control acarbose, whereas compounds 5 and 6 exhibited appreciable effects. An enzyme kinetic study revealed that compound 7 is a non-competitive inhibitor of a -glucosidase. This is the first report of the chemical constituents with biological activity from D. tortile.

Keywords:Dendrobium tortile; Orchidaceae; a -glucosidase; 2(5H)-furanone; bisbibenzyl. © 2016 ACG Publications. All rights reserved.