Mutagenicity and antioxidant assessment of Stachitarpheta jamaicensis (L.)Vahl.

Stachitarpheta jamaicensis (L,) Vahl, is a member of the Verbenaceae common ly used in Cuba, mainly as vermifugue and against diarrhoea, The mutagenic potential of a hydroalcohol extract of its aerial parts was assessed in vit ro using the Salmonella/microsome assay and in vivo in the mouse bone marro w micronucleus test, No positive response was observed in a battery of four Salmonella typhimurium strains employed: TA 1535, TA 1537, TA 98 and TA 10 0, when exposed to concentrations up to 5 mg/plate, with and without mammal ian metabolic activation. In the same way, no increase in the micronucleus frequency in mitotic erythropoietic tissue was observed when animals were a dministered the extract orally in doses of 500, 1000 and 2000 mg/kg, The ex tract inhibited lipid peroxidation in the rat liver microsomal fraction (IC 50 = 3.6 mug/mL) but it does not seem to be an effective OH radical scaveng er (IC50 = 76.7 mug/mL). Noteworthy, it increased in a dose dependent way t he level of revertant colonies in E, coli IC 203, a strain sensitive to oxi dative mutagenesis, when assayed together with hydrogen peroxide and ferrou s sulphate, which suggests a pro-oxidant action. Copyright (C) 2001 John Wi ley & Sons, Ltd.