Studies of arthropods have fundamental importance to identifying both ant species and microorganisms they carry. The objective of this study was to identify ant morph species found in residences, characterize the bacteria associated with the ants, assess bacterial resistance to antibiotics and analyze the plasmid profiles of the microorganisms found. The ant collections were carried out in the kitchens of 50 residences in the daytime. The bacteria were quantified and the samples were confirmed for the presence of plasmids. The data demonstrate that Pheidole sp. (74%) was the most frequent ant among those isolated; the microbiology analysis showed that the genus Sthaphyloccocus sp. (90%) was the most prevalent bacterial genus found on ants. This research presented a low frequency of Klebsiella sp. (2%), Enterococcus sp. (2%) and Vibrio cholera (2%). The ants classified as Pheidole sp. and Paratrechina sp. showed greater presence of microorganisms in the ants' cuticule, and Pheidole sp. was prevalent in relation to other ant species. Resistance was found to the antibiotics ampicillin, erythromycin and penicillin. Since there was no plasmid in the samples, it can be suggested that this tolerance is of chromosomal bacterial origin.

Osteosarcoma is the most commonly diagnosed malignant bone tumor in humans, with a higher incidence in children and young people. It is highly aggressive and has a high metastatic potential. Its treatment is based on both chemotherapy and surgical intervention. However, currently used chemotherapeutic agents, such as doxorubicin, have several adverse effects on the patient. Therefore, there is a growing demand for new chemotherapeutic agents that stimulate new researches, such as those involving compounds extracted from plants, such as the gabirobeira. In this study, we aimed to evaluate the cytotoxic effects of ethanolic extract, both crude and ethyl acetate, of gabirobeira leaves on osteosarcoma cells in vitro. Cytotoxicity was evaluated using the Trypan blue exclusion method and the IC50 values were calculated using the tetrazolium reduction method. The ethanolic extract of gabirobeira leaves showed a cytotoxic effect on osteosarcoma cells in vitro. The group treated with the crude extract at 1. 0μL mL-1 concentration for 48 hours showed higher cytotoxicity and the lowest IC50 value for this extract was found in the 24 to 48 hours interval. The ethanolic extract of gabirobeira leaves is cytotoxic for osteosarcoma cells.