Phytochemical investigation of the roots of Solanum melongena L. resulted in the isolation of ten terpenes and sixteen lignans, including a new triterpene saponin, officinoterpenoside E (1) and twenty-five known compounds (2-26). All compounds were firstly isolated from S. melongena except 2, 13, 21, 22. The structures of these compounds were determined by 1 D and 2 D NMR spectra referring to the literatures, together with high-resolution mass spectrometric analysis. All compounds were evaluated for the cytotoxicity against three cancer cell lines (HepG2, Hela, and MCF-7) in vitro. The results showed that compounds 1, 6, 20, 25 and 26 exhibited moderate cytotoxicity against HepG2, Hela and MCF-7 cells with IC50 values in the range of 16.8 ± 1.7 to 29.1 ± 1.9 μM. Therefore, these terpenoids and lignans may have potential biological activity, and also seemed to be of great chemotaxonomic value for S. melongena.
Keywords: Solanaceae; Solanum; cytotoxicity; lignan; natural product; terpene.