Assessment of cytotoxicity and genotoxicity of different chemotypes of Ophiorrhiza mungos and camptothecin on Allium cepa root tip and floral buds
摘要
Ophiorrhiza mungos L. (OM) (Rubiaceae) houses camptothecin (CPT), a potent anticancer molecule. OM has been reported in traditional medicine and folklore in the treatments of stomatitis, ulcers, inflammation, wounds, snakebite, body pain, cancer, and bacterial and viral infections. In this study, Allium cepa L. (onion) root tip and floral bud assays were performed to find out any cytotoxic and genotoxic effects of the plant chemotypes/populations and its active compound, CPT, on plant mitotic and meiotic cells. Five chemotypes of the plant collected from different locations of Darjeeling district as well as standard CPT were investigated for their effects on mitotic index (MI) in A. cepa root tip cells. Besides, their effects were also investigated on the root tip cells and floral buds of onion to find out their potential in causing chromosomal aberrations. Methanol extracts of the plant chemotypes have shown very minimal effects on MI and in higher concentrations, showed some chromosomal aberrations such as chromosomal stickiness, anaphase bridges/late separation, multipolarity, micronucleus formation, binucleate and multinucleate conditions and others. CPT, on the other had demonstrated more profound effects on MI as well as in causing chromosomal aberrations in mitotic-cells. However, floral bud cells were unaffected by both the plant extract as well as CPT. Further study is needed to replicate the genotoxicity and cytotoxicity of OM and CPT in animal cells to find out its effects on noncancerous somatic/germ cells and their ability to kill the cancer cells selectively.