β-Glucosidase inhibitory activities of phenylpropanoid glycosides, vanicoside A and B from Polygonum sachalinense rhizome

The phenylpropanoid glycosides, vanicoside A and B, isolated from rhizomes of giant knotweed (Polygonum sachalinense) showed β-glucosidase inhibitory activity, with IC50 values of 59.8 and 48.3 μg/ml (59.9 and 50.5 μM), respectively. In contrast, p-coumaric acid and ferulic acid, corresponding to phenylpropanoyl moieties of vanicosides, exhibited very little inhibition.