Lignan Compounds from the Strobilanthes bantonensis Leaves and their Bioactivity on Nitric Oxide Production Inhibitory and Antioxidant

Strobilanthes bantonensis is a medicinal herb used by the Tay ethnic group in Vietnam to treat gastritis and high fever. Research on the species has primarily focused on its taxonomy, chloroplast genes, and DNA barcoding. There has not yet been a comprehensive study of the phytochemical constituents and their biological activities. The compounds isolated were (+)-5,5’-dimethoxy-9-O-(β-D-glucopyranosyl)lariciresinol (1), (+)-lyoniresinol 3α-O-β-D-glucopyranoside (2), (-)-lyoniresinol 3α-O-β-D-glucopyranoside (3), and acanthoside B (4). All compounds were reported for the first time from S. bantonensis. Compounds 1-4 exhibited moderate nitric oxide (NO) inhibition with IC50 values ranging from 36.56 - 49.21 µM and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals with SC50 values ranging from 16.87 - 29.72 µM. These results suggest the use of S. bantonensis for the production of drugs and functional foods with anti-inflammatory and antioxidant effects.