Genotoxic and antigenotoxic potential of the aqueous leaf extracts of Amaranthus spinosus Linn. using Allium cepa assay

• Higher doses of plant extract induce mitodepressive and clastogenic effects.
• A lower concentration of plant extract reverts the clastogenicity induced by H2O2.
• Reduced mitotic index indicates antiproliferative activity of the plant extract.
• Severe clastogenicity induced by the plant extract indicates its genotoxicity.
• Results revealed the genotoxic and antigenotoxic property of A. spinosus L. extract.

The aim of the present study was to evaluate the possible genotoxic effects of A. spinosus leaf extracts on Allium cepa root meristematic cells and its antigenotoxic effects against H2O2-induced genetic damage in A. cepa. The excessive reduction in mitotic index (MI) (A4, 3 h, 23.37 ± 1.41) and extremely significant (P < 0.001) levels of clastogenicity (A4, 3 h, 98.14 ± 0.70) was observed after genotoxicity assay. The clastogenic abnormalities observed include bizarre nucleus, chromosome bridges, cytomixis, etc. In antigenotoxicity studies, initial toxicity was induced by two concentrations (7% and 3%) of H2O2. Higher percentage of nuclear lesions in treatment with H2O2 (99.27 ± 0.19) and its significant reduction after modulatory treatment (5 mg/L; 32.25 ± 7.69) was observed in the results, and indicates the chemopreventive activity of the plant extract at a critical concentration (5 mg/L). Here, the extent of antimutagenicity at this specific concentration (5 mg/L) was strong as the percentage of inhibition was greater than 40% (67.51 ± 8.68). The results demonstrated that the aqueous plant extract of A. spinosus have the ability to inhibit the oxidative damage induced by the direct-acting mutagen (H2O2) at a precise concentration.