Toxic Effects of Aqueous Extract of Plectranthus amboinicus (Lour) Spreng on Allium cepa

Aims: Plectranthus amboinicus (Lour) Spreng. belonging to the Lamiaceae family being extensively used in folk medicine for its anti-inflammatory effects, nonetheless, there is a lack of more substantial data on the toxicogenetic effects of this preparations. This study aimed to evaluate possible cytotoxic effects of aqueous extract of leaves of Plectranthus amboinicus on Allium cepa assay.

Methods: Distilled water was used as negative control and a solution of copper sulfate was used as positive control. Also a qualitative chemical screening for the identification of the major classes of active constituents were performed.

Results: The results demonstrate the presence of diterpenes and flavonoids, and a decreased in the mitotic index as the concentrations of extract increased.

Conclusions: These findings suggest that a toxic effect at high doses of Plectranthus amboinicus can be related to the presence of flavonoids and diterpenes.