Chemical constituents and antiviral activity from marine endophytic fungi from red sea alga Padina pavonica

Three endophytic fungal strains,fusarium equiseti,scopulariopsis fusca and geotrichum candidum were isolated from the inner tissue of the brown alga padina pavonica,collected from the red sea. the organic extracts of their liquid cultures were evaluated for their inhibition of hepatitis c virus (hcv) ns3-ns4a protease. as a result,f. equiseti showing a high-level inhibition of hcv protease (ic50 27.0 µg/ml) was selected for further investigation on its secondary metabolites. the fungus was identified by its morphology and 18s rdna. bioassay-guided fractionation of the etoac extract of the fungus culture broth revealed seven known metabolites. the structures of these metabolites were determined by ms and nmr spectral analysis. the isolated compounds were explored for inhibition of hcv ns3-ns4a protease activity.