Antiviral flavonoids from Mosla scabra

An ethanolic extract and ethyl acetate fraction (EFMS) prepared from Mosla scabra showed potential inhibition against influenza viruses. The compounds isolated from EFMS were elucidated to be ursolic acid (1), 5-hydroxy-6,7-dimethoxyflavone (2), 5-hydroxy-7,8-dimethoxyflavone (3), apigenin (4) and acacetin (5) based on their spectral analysis. Compounds 2, 3, 4 and 5 showed significant anti-influenza viruses activities. Compared with ribavirin, EFMS appeared to have similar efficacy against influenza viruses, was considered to be less toxic and may warrant further evaluation as a possible agent for the treatment of influenza. The ethanolic extract and solvent soluble fractions of the herb were screened for antiviral activities in MDCK cells by the CPE reduction assay. Four activity compounds were isolated from antiviral fraction. The antiviral fraction and the compounds extracted from Mosla scabra (EFMS) appeared significant anti-influenza virus A activities. [Display omitted]