Evaluation of the cytotoxic potential of the medicinal species of Croton antisyphiliticus

The species Croton antisyphiliticus, a native plant from the Brazilian Cerrado, has diterpenes as its chemical components. Diterpenes have numerous pharmacological properties and as such there is an economic interest in the Croton genus. The objective of the present work is to evaluate the cytotoxic activity of isolated diterpene and plant extracts obtained from roots and callus culture of C. antisyphiliticus against breast carcinoma cell lines (MCF7) and normal fibroblast cells (3T3). The cells were cultivated at 37^oC in a humid atmosphere containing 5% CO₂ and DMEM culture medium supplemented with 10% foetal bovine serum. The cells were distributed into 96-well plates (5×10³ cells/well) 24 hours before the assay. Next, the cells were incubated for 48 hours at different sample concentrations, that is, ranging from 100 to 4ug/mL and 1% DMSO (solvent control used for dilution). The cytotoxicity was evaluated by using the MTT colourimetric method. Doxorubicin was used as positive control. The results have revealed existence of cytotoxic activity in the assayed extracts as well as in the diterpene isolated from tumour line cells, thus demonstrating the potential of Croton antisyphiliticus diterpenes as a possible source of anti-cancer agents.