Atividade antimicrobiana de extrato de Brosimum Gaudichaudii Trécul. contra bactérias isoladas de lesões de pés diabéticos

Abstract

INTRODUCTION: Brosimum gaudichaudiiTrécul. isa plant of the Moreaceae family, found in the Cerradoregion of Brazil and tradionally used for the treatment of patients with vitiligo. OBJECTIVE: In our study, antimicrobial activities of the ethanol stem bark and leaf extracts of Brosimum gaudichaudiiTrécul. were evaluated against 68 multiresistant bacterial strains, which were isolated from diabetic foot patients, and 6 ATCC strain of Escherichia coli (25922), Pseudomonas aeruginosa (27853), Proteus mirabilis (12453), Citrobacter yougae (29935), Staphylococcus aureus (25923), Streptococcus pyogenes (0015). METHODS: The susceptibilities of the microbial strains to different plants extracts were tested using Disc Diffusion Method, Determination of Minimum Inhibitory Concentrationusing broth microdilution and Minimum Bactericidal Concentration. The efficacy of these extracts and of methodology used were analyzed by statistical methods. RESUSTS AND DISCUSSION: The highest antibacterial activity against most bacterial specieswas shown by bark extracts of Brosimum gaudichaudii Trecul. However, the leaf extracts also showed high antibacterial activity against S. aureus and Pseudomonas aeruginosa, bacteria that became resistant to the antibiotics most commonly used to treat Diabetic Foot Infections. Compared with disk diffusion, broth microdilution was more appropriate for quantitatively determining the antimicrobial activity of stem bark and leaf extracts of Brosimum gaudichaudii Trecul. However, our study suggested that the need to apply multiple methods when conducting in vitro antimicrobial susceptibility testing of plants extracts. There was a statistically significant interaction between antibiotics and bark extracts against gram positive bacteriaand between the combinations of stem bark and leaf extracts against gram positive and gram negative bacteria. These results suggest the presence of bioactive compounds that may synergistically contribute to activity anti bacterial. CONCLUSIONS: On the basis of the present finding, Brosimum gaudichaudii Trecul. stembarkand leafextract might be a good candidate in the search for a natural antimicrobial agent against the multiresistant bacterial strains.