Dedifferentiation of leaf explants and cytotoxic activity of an aqueous extract of cell cultures of Lantana camara L.

Several secondary metabolites are present in Lantana camara L. as its leaves serve as reservoirs for various bioactive compounds. Callus cultures of L. camara were induced from leaf discs incubated on Murashige and Skoog medium supplemented with 5 mu M 6-benzyladenine, 1 mu M 2,4-dichlorophenoxyacetic acid, and 1 mu M alpha-naphthalene acetic acid (NAA). An aqueous extract (0.23%), obtained from these calli (50 g dry mass), had an apparent cytotoxic effect on HeLa cells with an IC50 value of 1,500 mu g/ml in 36 h. A dose-time dependent activity of the extract was established wherein higher dosage exhibited increased activity; however, over time cell necrosis was observed.