Cytotoxic and Genotoxic Effect of Aqueous Leaf Extract of Salvia officinalis L. on Allium cepa Root Meristem Cells

The cytotoxic and genotoxic effects of aqueous extracts of Salvia officinalis L. (SAGE) on the root meristem cells of Allium cepa were determined using an Allium cepa cytogenetic assay. After four days, root growth inhibition was determined for different concentrations of extract (0–20%) using the cytogenetic assay to establish the EC50 value based on mean root lengths. Cytogenetic effects were evaluated by calculating mitotic indices and measuring the number of chromosomal aberrations. One of the primary objectives of this study was to show the dose-response relationship of the aqueous extract of S. officinalis L. with respect to inhibition of root growth. This relationship is represented in the results of the Allium cepa bioassay. Inhibition of root growth was shown to increase in a dose-dependent manner, with the EC50 identified as 20% aqueous extract S. officinalis L. The percentage of mitotic index was increased at various lower concentrations of the aqueous extract, but this increase represented metaphase arrest rather than mitotic stimulation. As the concentration of the aqueous extract increased, however, the percentage of mitotic index decreased, indicating that mitodepression was present for those concentrations. In addition, other chromosomal aberrations were observed further indicating the cytotoxic and genotoxic properties of the aqueous extract S. officinalis L.