New stilbene metabolites isolated from the tuber of Bletilla striata and their biological assessment

AbstractA phytochemical investigation of the tuber of Bletilla striata afforded eight stilbene derivatives, including a new bibenzyl (1) and two new phenanthrene (2 and 3). The structures of these compounds were elucidated using a combination of spectroscopic analyses. Further, the anti-inflammatory activity of all the compounds was evaluated to assess their capability to inhibit nitric oxide (NO) production by RAW 264.7 macrophages. The bioactive screening revealed that compounds 4 and 7 exhibited moderate inhibitory effects against NO production with the IC50 values 38.7 and 16.7 μM, respectively.Keywords: Bletilla striatastilbene metabolitesnitric oxideinhibitory activity Disclosure statementNo potential conflict of interest was reported by the authors.Additional informationFundingThis work was financially supported by the Natural Science Key Research Program of Anhui Province University (2022AH050451), the Natural Science Key Research Program of Anhui University of Chinese Medicine (2021efylc10), the Natural Science Research Program of Anhui University of Chinese Medicine (2020efyzc13), the Key Project of the National Science Fund of Anhui Province (No. KJ2017A277), the Key Project of the Open Fund of Anhui Engineering Laboratory for Medicinal and Food Homologous Natural Resources Exploration (No. YSTY2022009) and the Key Project of the Clinical Research Fund of Anhui University of Chinese Medicine (No. 2021efylc03).