α-Glucosidase and pancreatic lipase inhibitory effects and anti-adipogenic activity of dendrofalconerol B, a bisbibenzyl from Dendrobium harveyanum

Pancreatic lipase is the key enzyme for lipid digestion. Inhibition of this enzyme can reduce lipid absorption and prevent obesity disease. A methanol extract prepared from the whole plant of Dendrobium harveyanum exhibited strong anti-lipase effect. Chromatographic separation of this plant results in the isolation of 5 known compounds including 3,4-dihydroxy-5,4'-dimethoxybibenzyl (1), dendrofalconerol A (2), dendrofalconerol B (3), daucosterol (4) and dendrocandin B (5). The structures were determined by analysis of their spectroscopic data. All compounds were evaluated for their lipase and alpha-glucosidase inhibitory activities. Dendrofalconerol B (3) showed noticeable lipase and alpha-glucosidase inhibitory effects when compared with the positive controls. Dendrofalconerol B was further studied and found to show strong anti-adipogenic activity through the suppression of PPAR gamma and OEBP alpha expression, resulting in the reduction of cellular lipid accumulation in preadipocyte 3T3-L1 cells. Taken together, these results strongly support the potential development of dendrofalconerol B as a safe and effective treatment for metabolic diseases. (C) 2021 SAAB. Published by Elsevier B.V. All rights reserved.