Identification of a new α‐glucosidase inhibitor: Alkyl ferulate ester derived from unripe fruits of Solanum torvum Swartz

Abstract In this study, the phytochemical compositions and α ‐glucosidase inhibitory activity of the ethyl acetate extract derived from the unripe fruits of Solanum torvum Swartz have been investigated. The investigation led to the isolation of a new isoferulate fatty alkyl ester, solacanin B ( 1 ), in addition to eight known compounds, including lyciumol A ( 2 ), ethyl caffeate ( 3 ), caffeic acid ( 4 ), scopoletin ( 5 ), p ‐hydroxybenzaldehyde ( 6 ), p ‐hydroxybenzoic acid ( 7 ), vanillic acid ( 8 ) and 1‐ O ‐palmitoylglycerol ( 9 ). The structural elucidation of these compounds was achieved through extensive spectroscopic analyses and reference literature. Bioactivity assay of all compounds demonstrated that compounds 1 – 4 , and 7 showed more potent α ‐glucosidase inhibition activities, with IC 50 values of 48.4, 29.3, 38.8, 95.0, and 186.6 µ m , respectively, than that of positive control acarbose (IC 50 , 214.5 µ m ).