Higher yielding isolation of kinsenoside in Anoectochilus and its antihyperliposis effect

A higher concentration of kinsenoside, 3-(R)-3-beta-D-glucopyranosyloxybutanolide (1), was detected in the crude drug Anoectochilusformosanus, and A. koshunensis by HPLC analysis. A methylation reaction occurred to give methyl ester (4) when the lactone ring of 1 was cleaved by silica gel catalysis using methanol containing solvent used in the purification step resulting in difficulty to purify 1. To avoid the cleavage reaction, a reversed-phase or silica gel column without methanol was used to give a high yield of 1. In an anti-hyperliposis assay using high-fat diet rats, 1 significantly reduced the weights of body and liver, and also decreased the triglyceride level in the liver compared to those of control rats. On the other hand, the epimer of 1, 3-(S)-3-beta-glucopyranosy-loxybutanolide (2), trivially named goodyeroside A, which was isolated from Goodyera species, had no effect for anti-hyperliposis. In aurothioglucose-induced obese mouse, 1 suppressed the body and liver weight increase, significantly ameliorated the triglyceride level in the liver, and also reduced the deposition of uterine fat-pads.