Lignin reduces ofloxacin-induced mutagenicity in Euglena assay

The possible protective effect of sulphur-free beech lignin polymer on the mutagenicity of ofloxacin in Euglena gracilis was studied. The generation o f oxygen species by ofloxacin and their possible interaction with lignin wa s verified by physico-chemical measurements. The UV absorbance spectra of o floxacin with and without lignin showed no interaction between these two co mpounds. The production of superoxide anion radical (O-2(-)) by ofloxacin w as significantly reduced in the presence of lignin (AIR = 0.57 +/- 0.03, p< 0.01). Lignin, at concentrations of 125 and 250 mu g/ml decreased the E. gr acilis bleaching activity of ofloxacin to 39.9% and 2.8%, respectively. A l ignin concentration of 500 mu g/ml eliminated the bleaching activity of ofl oxacin very efficiently. Our results are consistent with the concept that l ignin biopolymer has the capability of reducing genotoxic activity by scave nging reactive oxygen species.