Abstract

Obi Ikem and Emeka Uzor

Genotoxic and cytotoxic effects of monosodium glutamate (MSG) used as flavor enhancer in foods was analyzed using the Allium cepa assay. Onion bulbs were grown at different concentrations (1, 3, 5 and 7 g/L) of MSG dissolved in distilled boiled water and also evaluated when dissolved in distilled water without boiling; a control group was also set up. The macroscopic (morphology and color of roots) and microscopic (mitotic index and chromosomal aberrations) parameters of Allium root tips were studied. MSG inhibited growth of A. cepa root tips in all concentrations and was significant on days 2 to 5 in distilled water without boiling and on days three to five when dissolved in boiled distilled water. MSG also reduced the number of roots growing from primodium in all test concentrations as compared to control and the least was observed in 5 g and 7 g/L. Color of root tips range from brownish to dark brown or black in higher MSG concentrations. Sticky chromosomal aberration at telophase was most commonly induced in all the MSG test concentrations. MSG decreased mitotic index of A. cepa cells at all the test concentrations but this result was not statistically different. There was no significant difference in total chromosomal aberrations in all experimental set up as compared to control.