Synergistic antimutagenic effect of isothiocyanates against varied mutagens

Although plant foods provide an array of nutrients in the human diet, our knowledge of how these nutrients are interacting among each other at molecular level is limited. Among these, glucosinolates are the most important secondary metabolites, which are readily hydrolyzed to a variety of products including isothiocyanates. The current study emphasizes on the antimutagenic potential of three isothiocyanates (ITCs) viz. allyl, benzyl and 3-butenyl ITCs (individually and in binary combinations) in Ames Salmonella histidine reversion assay using Salmonella typhimurium TA98 and TA100 tester strains. Three different mutagens were used in the study including two direct acting mutagens [4-nitro-o-phenylenediamine (frame shift mutagen) and sodium azide (base substitution mutagen)] and one indirect acting mutagen [2-aminofluorene]. Furthermore, S9 fraction from rat liver microsomes was used to mimic the mammalian system. The study points towards the ability of ITCs to act as potent inhibitors of mutagenicity induced by different mutagens. Benzyl ITC was found to be the most effective among the three. Computation of combination effects was done on the basis of combination index values. It was observed that ITCs in combination induced a stronger antimutagenic response and that too at relatively low concentrations, without any signs of toxicity.