Ficus racemosa Stem Bark Extract: A Potent Antioxidant and a Probable Natural Radioprotector
V. P. Veerapur1, K. R. Prabhakar1, Vipan kumar Parihar1, Machendar Reddy Kandadi1, S. Ramakrishana2, B. Mishra4, B. S. Satish Rao2, K. K. Srinivasan3, K. I. Priyadarsini4 and M. K. Unnikrishnan1
1Department of Pharmacology, Manipal College of Pharmaceutical Sciences, 2Radiobiology, Kasturba Medical College, 3Department of Pharmaceutical Chemistry, Manipal College of Pharmaceutical Sciences, Manipal-576 104, Karnataka, India and 4Radiation and Photochemistry Division, Bhabha Atomic Research Centre, Mumbai-400085, India
Ethanol extract (FRE) and water extract (FRW) of Ficus racemosa(family: Moraceae) were subjected to free radical scavenging both by steady state and time resolved methods such as nanosecond pulse radiolysis and stopped-flow spectrophotometric analyses.FRE exhibited significantly higher steady state antioxidant activity than FRW. FRE exhibited concentration dependent DPPH,ABTS•–, hydroxyl radical and superoxide radical scavenging and inhibition of lipid peroxidation with IC50 comparable with tested standard compounds. In vitro radioprotective potentialof FRE was studied using micronucleus assay in irradiated Chinese hamster lung fibroblast cells (V79). Pretreatment with different doses of FRE 1h prior to 2 Gy -radiation resulted in a significant(P < 0.001) decrease in the percentage of micronucleatedbinuclear V79 cells. Maximum radioprotection was observed at20 µg/ml of FRE. The radioprotection was found to be significant(P < 0.01) when cells were treated with optimum dose of FRE(20 µg/ml) 1 h prior to 0.5, 1, 2, 3 and 4 Gy -irradiation compared to the respective radiation controls. The cytokinesis-block proliferative index indicated that FRE does not alter radiation induced cell cycle delay. Based on all these results we conclude that the ethanol extract of F. racemosa acts as a potent antioxidant and a probable radioprotector.