Antimutagenic effect of black tea extract using 'rodent dominant lethal mutation assay'

The antimutagenic effect of black tea extract has been evaluated with the 'Dominant Lethal Assay' in Swiss albino mice using benzo[a]pyrene [BaP] as a mutagen. BaP was given through the intraperitoneal (i.p.) route at a single dose of 100 mg/kg b.w. to male mice once only. The animals were given 1, 2 and 4% aqueous solution of black tea as sole source of drinking solution prior to BaP. The pregnant females were analyzed for living implants, pre- and post-implantation losses. The results revealed that during mating weeks, BaP caused a reduction in implants and an increase in pre- and post-implantation losses. The protective effect of tea solution on BaP-induced mutagenicity was observed. The number of living implants increased and dead implants decreased significantly in the animals kept on 2 and 4% tea solution. The increase in dominant lethal mutation rate by BaP was inhibited by black tea extract. Four percent tea solution alone did not produce dominant lethality, and reveals that it is non-toxic/non-mutagenic to sperm. Hence the study suggests that tea has a protective effect against BaP-induced genetic damage to germ cells in Swiss albino mice.