ETHNOPHARMACOLOGICAL RELEVANCE:Tinospora cordifolia (Willd. Hook. f. & Thomson; family: Menispermaceae), has a long history of use in various traditional medicinal systems including "Ayurveda". It is reported to possess anticancer, antidiabetic, antimicrobial, antispasmodic, and antiinflammatory activities. T. cordifolia has also been well documented for production of various bioactive metabolites and their antioxidant activity, but the microorganisms associated with it have been least explored for the same properties. AIM OF THE STUDY:Aim of the present study was to evaluate antioxidant and in vivo genoprotective potential of phenolic compounds produced by an endophytic fungus Cladosporium velox TN-9S isolated from T. cordifolia. MATERIALS AND METHODS:The isolate of C. velox TN-9S was cultivated in malt extract medium and extracted with ethyl acetate. Total phenol content was determined by Folin Ciocalteu reagent. The antioxidant activity was measured in terms of DPPH and FRAP assay. The in vivo genoprotective activity was assessed using fish Channa punctatus as model. Identification of phenolic compounds was carried out using RP-HPLC. The fungal extract was evaluated for biosafety using Salmonella typhimurium His- strain and CHO cell lines for mutagenicity and cytotoxicity, respectively. RESULTS:The total phenolic content in the ethyl acetate extract of the fungus was determined to be 730μg gallic acid equivalent/mL. The extract evinced significant antioxidant activity with IC50 value of 22.5µg/mL in DPPH scavenging assay. The phenolic extract showed good in vivo genoprotective activity against the genetic damage induced in fish C. punctatus after treatment with a non-ionic surfactant 4-nonylphenol. RP-HPLC analysis revealed the presence of peaks corresponding to various phenolic compounds in the extract. Mutagenicity and cytotoxicity results revealed the extract to be nonmutagenic and non cytotoxic in nature. CONCLUSION:The results indicate the potential of an endophytic C. velox isolated from T. cordifolia as a producer of phenolic compounds with antioxidant and genoprotective activities which could be exploited in pharmaceutical industry. The ability of endophytes to produce similar compounds as the host, is also revealed in the present study.