Evaluation of cytotoxicity and efficiency of antioxidant protection of hydrophilic derivatives of 2,4,6-trialkylphenols in Escherichia coli cells

The effects of five new derivatives of 2,6-dialkyl-4-propylphenol containing different ionogenic groups (-SO3Na, -S-SO3Na, -S-(NH2)2Cl) in the para position on survival of the E. coli AB1157 strain and its isogenic strain deficient in repair enzyme genes have been investigated in the presence and in the absence of hydrogen peroxide. Survival of cells treated with hydrogen peroxide was markedly increased in the presence of sodium (3-(3,5-dimethyl-4-hydroxyphenyl)propyl)-1-sulphonate (C1). Replacement of methyl substituents at ortho-position of C1 for tert-butyl or cyclohexyl groups decreased cell protection against exogenous hydrogen peroxide. Among 2,6-di-tert-buthylphenol the compound with the thiosulphonate group demonstrated properties similar to its sulphonate analog, whereas 3 mM isothiuronium chloride completely suppressed cell growth both in the absence and in the presence of hydrogen peroxide. Thus, among the tested compounds C1 may be considered as the most promising antioxidant.