EVALUATION OF ANTIMICROBIAL AND CYTOTOXIC ACTIVITIES OF PLANT EXTRACTS FROM SOUTHERN MINAS GERAIS CERRADO

The antimicrobial activity of plant hidroethanolic extracts on bacteriaGram positive, Gram negative, yeasts, Mycobacterium tuberculosis H37and Mycobacterium bovis was evaluated by using the technique of Agardiffusion and microdilution in broth. Among the extracts evaluated by Agar diffusion,the extract of Bidens pilosa leaf presented the most expressiveaverage of haloes of growth inhibition to the microorganisms, followed by the extractof B. pilosa flower, of Eugenia pyriformis'' leafand seed, of Plinia cauliflora leaf which statistically presentedthe same average of haloes inhibitory formation on bacteria Gram positive, Gramnegative and yeasts. The extracts of Heliconia rostrata did notpresent activity. Mycobacterium tuberculosis H37 andMycobacterium bovis (BCG) appeared resistant to all the extracts.The susceptibility profile of Candida albicans andSaccharomyces cerevisiae fungi were compared to one another andto the Gram positive Bacillus subtilis, Enterococcusfaecalis and the Gram negative Salmonella typhimuriumbacteria (p > 0.05). The evaluation of cytotoxicity was carriedout on C6-36 larvae cells of the Aedes albopictus mosquito. Theextracts of stem and flower of Heliconia rostrata, leaf and stem ofPlinia cauliflora, seed of Anonna crassifloraand stem, flower and root of B. pilosa did not present toxicity inthe analyzed concentrations. The highest rates of selectivity appeared in theextracts of stem of A. crassiflora and flower of B.pilosa to Staphylococcus aureus, presenting potentialfor future studies about a new drug development.