Antimutagenic Effect of Green Tea Extracts in Reverse Mutation Assay

In the present investigation, antimutagenic effect of petroleum ether, chloroform, methanol and water extracts of green tea was evaluated in Salmonella typhimurium TA-98 and TA-100 strains. Well known mutagens like sodium azide and daunomycin were added at a concentration of 10µl and 6µl per plate respectively resulted in the induction of histidine revertant colonies. However addition of 10 µl of petroleum ether, chloroform, ethanol and water extracts of green tea to 10 µl of sodium azide and 6 µl of daunomycin treated plates resulted in the inhibition in the number of histidine revertant colonies. Furthermore, supplementation with all the four extracts of green tea at a concentration of 10 µl per plate respectively in the presence of S9 fraction also led to significant inhibition in sodium azide and daunomycin induced colony formation. The antimutagenic activity of ethanolic extract of green tea was found to be higher than that of the other extracts. Hence the study revealed that green tea has protective efficacy in sodium azide and daunomycin induced mutagenicity in the test microbial system.