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 IC50 values of 48.4, 29.3, 38.8, 95.0, and 186.6 µm, respectively, than that of positive control acarbose (IC50, 214.5 µm).