α-Glucosidase Inhibitory and Glucose Uptake Stimulatory Effects of Phenolic Compounds From Dendrobium christyanum

Abstract

A methanolic extract from the dried root of Dendrobium christyanum Rchb.f. (Orchidaceae) exhibited α-glucosidase inhibitory activity and glucose uptake stimulatory effect. Chromatographic separation of the extract led to the isolation of 13 phenolic compounds (1-13). Their structures were determined by spectroscopic analysis. The isolates were then evaluated for in vitro α-glucosidase inhibitory and glucose uptake stimulatory activities. Methyl haematommate (1), methyl 2,4-dihydroxy-3,6-dimethylbenzoate (3), n-docosyl 4-hydroxy- trans-cinnamate (4), coniferyl aldehyde (6), 4,5-dihydroxy-2-methoxy-9,10-dihydrophenanthrene (7), gigantol (10), and diorcinolic acid (13) showed higher α-glucosidase inhibitory activity than the drug acarbose. Moreover, n-docosyl 4-hydroxyl- trans-cinnamate (4), vanillin (5), and coniferyl aldehyde (6) could enhance glucose uptake by L6 myotubes. Compounds 4 and 6 appear to be potential hypoglycemic agents since they possess both α-glucosidase inhibitory and glucose uptake stimulatory activities. This study is the first report on the chemical constituents and antidiabetic activity of D. christyanum.

Three Novel Biphenanthrene Derivatives and a New Phenylpropanoid Ester from Aerides multiflora and Their α-Glucosidase Inhibitory Activity

“…However, introducing methoxy groups to C-3 and C-5′ of 9 caused a total loss of activity, as seen in dihydrosinapyl dihydroferulate ( 4 ). A similar phenomenon, in which the presence of aromatic methoxy groups diminished α -glucosidase inhibitory activity, was earlier reported for p -coumarate esters of long-chain alcohols [ 71 ].…”

Constituents of Huberantha jenkinsii and Their Biological Activities

“…Interestingly, mangiferin (7) displayed a strong neuroprotective activity, with a 60.5 ± 1.7% The isolated compounds were further studied for antidiabetic potential. Compounds 3-7 were evaluated for α-glucosidase inhibitory activity using established protocols [21,22]. The alkaloids 1 and 2, however, were not tested due to their limited amounts.…”

“…Recently, we have found that some α-glucosidase inhibitors (AGIs) of natural origin also possessed the ability to stimulate glucose uptake by skeletal muscle cells [21,22]. This secondary biological activity has currently attracted research attention because it might help to increase the antidiabetic potential of these AGIs.…”

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Four Novel Phenanthrene Derivatives with α-Glucosidase Inhibitory Activity from Gastrochilus bellinus

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