Evaluation of Genotoxic and Cytotoxic Activities of Three Vegetables (Heinsia crinata, Justicia insularis and Lasianthera africana) Using Allium cepa Test

Heinsia crinata (Afzel.) G. Taylor (Rubiaceae), Justicia insularis T. Anderson (Acanthaceae family) and Lasianthera africana. P.Beav (Stemonuraceae), which are used as vegetables in the preparation of soups and as medicine traditionally to treat various diseases by the Ibibios were investigated for genotoxic and cytotoxic effects using Allium cepa test. The effects of the leaf extracts on the root meristem cells of Allium cepa were investigated using onion bulbs exposed to 2.5 mg/mL, 5mg/mL, and 10 mg/mL concentrations of the extracts for macroscopic and microscopic analysis. Tap water was used as a negative control and Methotrexate (0.1 mg/ml) was used as a positive control. There was statistically significant (p<0.05) inhibition of root growth depending on concentration by the extracts when compared with the negative control group. All the tested extracts were observed to have cytotoxic effects on cell division in A. cepa. The extracts induced chromosomal aberrations and micronuclei (MNC) formations in A. cepa root tip cells were significant (p<0.05) when compared with control group. The extracts treatment further induced cell death, ghost cells, cells membrane damage, and binucleated cells. These results suggest that the leaf extracts of Lasianthera africana, Heinsia crinata and Justicia insularis possess cytotoxic and genotoxic effects on A. cepa.