Anais do Congresso Paranaense de Microbiologia
IV Congress of Microbiology in Paraná

The use of plants for medicinal purposes is part of the reality of several regions and can be a therapeutic alternative for the treatment of infections in different contexts. However, there are still scientific gaps on the antimicrobial potential and pharmacological safety of different plant species that have popular use. Thus, this study aimed to evaluate the antimicrobial and mutagenic potential of medicinal plants used in the city of Dourados, MS, based on popular knowledge. The selection of the plants was made through a conversation with local healers and from a literature review to verify the pharmacological activities already evidenced for the species. The aqueous extracts were prepared by infusion of the leaves of the selected species. The Minimum Inhibitory Concentration (MIC) was evaluated by the broth microdilution method with concentrations ranging from 3.9 to 2000 µg/mL. Microorganisms from American Type Culture Collection, Staphylococcus aureus (25923), Bacillus cereus (11778), Salmonella Typhimurium (14028), Klebsiella pneumoniae (13883), Candida albicans (90028), Candida glabrata (2001), Candida krusei (6558), Candida tropicalis (750), and four clinical isolates of C. krusei from nasal and rectal swab, blood culture and urine culture were used. Mutagenic potential was evaluated by the Ames test using Salmonella Typhimurium strains TA98 and TA100, capable of identifying frameshift and base-pair substitution mutations, respectively. The species Apium graveolens, Miconia albicans and Pereskia aculeata were selected for the assays based on the conversation with the healers and bibliographic research. Miconia albicans presented MIC of 1000 µg/mL against K. pneumoniae and 500 µg/mL for ATCC strain and clinical isolates of C. Krusei. A. graveolens and P. aculeata did not present activity against the tested microorganisms. The extracts did not induce the increase of revertant colonies per plate in both strains, TA98 and TA100, not showing mutagenic potential by Ames test. Thus, the results obtained in this work demonstrated that M. albicans presents promising antifungal activity that can be used in the study of development of new drugs. Although A. graveolens and P. aculeata do not present antimicrobial activity, they can be considered safe regarding their mutagenic potential and can be used according to the indication of popular use and for the biological activities already reported in the literature.