Evaluation of the Genotoxic Potential againstH2O2-Radical-Mediated DNA Damage and Acute Oral Toxicity of Standardized Extract ofPolyalthia longifoliaLeaf

Abstract

Medicinal plants have been used in medicoculturally diverse countries around the world, where it is a part of a time-honoured tradition that is respected even today.Polyalthia longifolialeaf extract has been previously reported as an efficient antioxidantin vitro. Hence, the genotoxic effects ofP. longifolialeaf were investigated by using plasmid relation, comet, andAllium cepaassay. In the presence of  ∙OH radicals, the DNA in supercoil was start nicked into open circular form, which is the product of the single-stranded cleavage of supercoil DNA and quantified as fragmented separate bands on agarose gel in plasmid relation assay. In the plasmid relation and comet assay, theP. longifolialeaf extract exhibited strong inhibitory effects against H2O2-mediated DNA damage. A dose-dependent increase of chromosome aberrations was also observed in theAllium cepaassay. The abnormalities scored were stickiness, c-mitosis, bridges, and vagrant chromosomes. Micronucleated cells were also observed at the interphase. The results ofAllium cepaassay confirmed that the methanol extracts ofP. longifoliaexerted no significant genotoxic or mitodepressive effects at 100 μg/mL. Thus, this study demonstrated thatP. longifolialeaf extract has a beneficial effect against oxidative DNA damage. This experiment is the first report for the protective effect ofP. longifoliaon DNA damage-induced by hydroxyl radicals. Additionally in acute oral toxicity study, female rats were treated at 5000 mg/kg body weight ofP. longifolialeaf extract and observed for signs of toxicity for 14 days.P. longifolialeaf extract did not produce any treatment-related toxic effects in rats.