Mutagenic and antimutagenic assessment of methanol leaf extract of Myristica fragrans (Houtt.) using in vitro and in vivo genetic assays

The role of diets in causing cancers necessitates the ongoing search for natural antimutagens of promising anticancer therapeutics. This study determined the potential anticancer efficacy of the leaf extract of Myristica fragrans (Houtt.). Methanol leaf extract of M. fragrans (Houtt.) alone was screened for mutagenicity in the bacterial reverse mutation (Ames) test, using the Salmonella typhimurium TA100 strain, the Allium cepa, and the mouse in vivo bone marrow micronucleus tests. The antimutagenicity of this extract against benzo[a]pyrene- and cyclophosphamide-induced mutations was evaluated. An antioxidant test on the extract was performed with 2,2-diphenyl-1-picrylhydrazyl, using butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) as the standards, whereas its phytochemicals were elucidated by following the gas chromatography/mass spectrometry protocol. In S. typhimurium (TA100), the mutagenicity ratio at 200,500 and 1,000 mu g/well was >2. Cell division in the A. cepa root tips and mouse bone marrow was significantly (P <= 0.05) inhibited at 2,000 and 4,000 mg/kg, whereas the observed chromosomal aberrations and micronucleated polychromatic erythrocytes were non-dose-related and were insignificantly (P >= 0.05) different from the negative control. Inhibition of benzo[a]pyrene- and cyclophosphamide-induced mutagenicity by this extract was above 40%. Half-maximal inhibitory concentration of the extract in the antioxidant test was lower than that of BHA and BHT. Phytochemical compounds, possessing antioxidant activity, may be responsible for the observed effects, suggesting a strong antimutagenic activity of the MeOH leaf extract of M. fragrans, a necessary characteristic of a promising anticancer agent.