Evaluation of the toxicity, cytotoxicity and antibacterial activity of Tibouchina papyrus (Pohl) Toledo (Melastomataceae)

The objective of this research was to perform a preliminary phytochemical study and investigate the toxicity, cytotoxicity and antibacterial activity of the species Tibouchina papyrus (Melastomataceae). The toxicity test was performed with the extracts against Artemia salina. The cytotoxic study was also performed against the following cell lines: promyelocytic leukemia (HL60), human colon carcinoma (HCT-116), breast carcinoma (MCF-7), prostate carcinoma (PC3), astrocytoma (SNB-19) and non-tumor cells (L929). Last, antibacterial activity was assessed through against Staphylococcus epidermidis (25923), Staphylococcus aureus (12228), Escherichia coli (25312) and Pseudomonas aeruginosa (27853). The phytochemical investigation indicated the presence of these metabolite groups: flavonoids, triterpenes, steroids and tannins. The methanolic extracts showed moderate antibacterial activity against S. aureus, S. epidermidis and P. aeruginosa. T. papyrus extracts showed high cytotoxic activity against promyelocytic leukemia cell lines (80.43 to 93.31%). The other lines did not reveal good activity against the extracts tested.