Pro-antioxidant activities of fractions of a novel camptothecin-producing endophyte (Entrophosphora infrequens).

Abstract

PURPOSE The overexploitation of wild medicinal flora for use in modern medicinal systems has led to a significant threat to the endemic medicinal flora. It is, therefore, imperative to develop biotechnological interventions to ensure regular availability of these bioactive compounds. METHOD: In the present study, with a view to developing a biotechnological alternative, an endophyteEntrophosphora infrequens was isolated from the inner bark of the medicinal plant Nothapodytes foetida. The endophyte was authenticated using CLUSTAL W-based phylogenetic analysis; subsequently its independent culture and unequivocal demonstration of production of camptothecin (CPT), an anti-cancer secondary metabolite was proved. RESULTS: A comparison was made between CPT(CPT devoid) and CPT+ (CPT enriched) fractions, followed by evaluation of their pro-antioxidant (biphasic) activity in lipid phase. Mechanistic analysis revealed a significant (p 65%), while Ferric Reducing Ability in Plasma (FRAP) equivalence value of CPT+ fraction was found to be 1.02 ± 0.04 times higher as compared to CPTfraction (time points x, 8x and 16x; x= 300s), explaining its prooxidant behavior at lower concentrations. CONCLUSIONS: In conclusion, the prooxidant activity positively correlated with the presence of CPT, acting in synergism/antagonism with other active constituents. The contrasting potential of both fractions indicates its usage as an anti-cancer drug and as antioxidants and/or radiomodulator.