Efficacy of golden rain tree against free radicals and H2O2-induced damage to pUC18/calf thymus DNA

ABSTRACT

Objective: To investigate the antioxidant and genoprotective potential of the methanol extract (METH-KP) along with its hexane fraction (HEX-KP) from the leaves of Koelreuteria paniculata (K. paniculata) Laxm. Methods: The antioxidant potential was checked using metal chelation assay, ABTS, DPPH (2,2-diphenyl-2-picryl-hydrazyl), reducing power and superoxide anion radical scavenging assay, Folin-Ciocalteu reducing capacity (FCR assay), Total flavonoid content (TFC assay) and genoprotective activity against the DNA damage induced by Fenton's reagent using pUC18/calf thymus. Results: Results showed that radical scavenging activities of the both test extract/fraction revealed a concentration-dependent antiradical activity in all the assays. In Metal chelation assay, METH-KP and HEX-KP showed 39.04% and 32.51% of scavenging at highest tested concentrations. The METH-KP exhibited IC50 of 54.54 μg/mL in ABTS, 115 μg/mL in DPPH, 110 μg/mL in reducing power and 135 μg/mL in superoxide anion radical scavenging assay while that HEX-KP was found to be very poor in radical scavenging in all the above assays. The phytochemical analysis showed good amount of phenolic and flavonoid compounds in METH-KP while the HEX-KP fraction lacks phenols. The METH-KP extract and HEX-KP fraction both showed DNA protective effect in Calf thymus/pUC18 DNA protection studies. Conclusions: The activity of METH-KP may be attributed to its polyphenolic constituents which needs further isolation of its active constituents which may lead to the development of novel drugs to combat cancer.