RESUMO
BACKGROUND: With the emergence of strains resistant to conventional antibiotics, it is important to carry studies using alternative methods to control these microorganisms causing important infections, such as the use of products of plant origin that has demonstrated effective antimicrobial activity besides biocompatibility. Therefore, this study aimed to evaluate the antimicrobial activity of plant extracts of Equisetum arvense L., Glycyrrhiza glabra L., Punica granatum L. and Stryphnodendron barbatimam Mart. against Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus mutans, Candida albicans, Candida tropicalis, and Candida glabrata, and to analyze the cytotoxicity of these extracts in cultured murine macrophages (RAW 264.7). METHODS: Antimicrobial activity of plant extracts was evaluated by microdilution method based on Clinical and Laboratory Standards Institute (CLSI), M7-A6 and M27-A2 standards. The cytotoxicity of concentrations that eliminated the microorganisms was evaluated by MTT colorimetric method and by quantification of proinflammatory cytokines (IL-1ß and TNF-α) using ELISA. RESULTS: In determining the minimum microbicidal concentration, E. arvense L., P. granatum L., and S. barbatimam Mart. extracts at a concentration of 50 mg/mL and G. glabra L. extract at a concentration of 100 mg/mL, were effective against all microorganisms tested. Regarding cell viability, values were 48% for E. arvense L., 76% for P. granatum L, 86% for S. barbatimam Mart. and 79% for G. glabra L. at the same concentrations. About cytokine production after stimulation with the most effective concentrations of the extracts, there was a significant increase of IL-1ß in macrophage cultures treated with S. barbatimam Mart. (3.98 pg/mL) and P. granatum L. (7.72 pg/mL) compared to control (2.20 pg/mL) and a significant decrease of TNF-α was observed in cultures treated with G. glabra L. (4.92 pg/mL), S. barbatimam Mart. (0.85 pg/mL), E. arvense L. (0.83 pg/mL), and P. granatum L. (0.00 pg/mL) when compared to control (41.96 pg/mL). CONCLUSIONS: All plant extracts were effective against the microorganisms tested. The G. glabra L. extract exhibited least cytotoxicity and the E. arvense L. extract was the most cytotoxic.
Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Doenças Estomatognáticas/microbiologia , Animais , Brasil , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Doenças Estomatognáticas/metabolismo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Several researches have been developed to search for new antimicrobial agents from plants, to be used in pharmaceutical products. The aim of this study was to evaluating in vitro antimicrobial properties of extracts glicolics (75%) of Psidium guajava L. (guava), Syzygium cumini L. (jambolan) and Pimpinella anisum L. (herbsweet) on standard strains of Candida albicans, Enterococcus faecalis, Staphylococcus aureus, Streptococcus mutans, Escherichia coli and Bacillus atrophaeus (spores). During the experiment, the minimal inhibitory concentration (MIC) was determined by broth dilution method, following by subcultivation in agar in order to determine the minimal microbicide concentration (MMC). The extracts showed the following CIM and MMC, respectively: Psidium guajava L 25% and 50% for C. albicans, E. faecalis and E. coli, 12.5% and 25% for S. mutans, and 3.12% and6.25% for S. aureus; Syzygium cumini L. 25% and 50% for C. albicans, 12.5% and 25% for E. faecalis and S. aureus, and 6.25% and 12.5% for E. coli and S. mutans; Pimpinella anisum L -12.5% and 25% for C. albicans and S. mutans,6.25% and 12.5% for E. faecalis and S. aureus, and 3.12% and 6.25% for E. coli. It could be concluded that, despite the resistance by B. atrophaeus, the extracts used showed antimicrobial potential on the other microorganisms.
Várias pesquisas vêm sendo desenvolvidas e direcionadas no descobrimento de novos agentes antimicrobianos provenientes de plantas, para serem aplicados em produtos farmacêuticos. O objetivo deste estudo foi avaliar in vitro a propriedade antimicrobiana de extratos glicólicos (75%) de Psidium guajava L. (goiabeira), Syzygium cuminiL. (jambolão) e Pimpinella anisum L. (erva-doce) sobre cepas padrão de Candida albicans, Enterococcus faecalis, Staphylococcus aureus, Streptococcus mutans, Escherichia coli e Bacillus atrophaeus (esporos). Foi determinada a concentração inibitória mínima (CIM) pelo método de microdiluição em caldo, seguindo-se de subcultivos emagar para determinar a concentração microbicida mínima (CMM). Os extratos apresentaram as seguintes CIM e CMM, respectivamente: goiabeira 25% e 50% para C. albicans, E. faecalis e E. coli; 12,5% e 25% para S. mutans, e,3,12% e 6,25% para S. aureus; jambolão 25% e 50% para C. albicans, 12,5% e 25% para E. faecalis e S. aureus, e,6,25% e 12,5% para E. coli e S. mutans; erva-doce 12,5% e 25% para C. albicans e S. mutans, 6,25% e 12,5% para E. faecalis e S. aureus, e 3,12% e 6,25% para E. coli. Conclui-se que, apesar da resistência apresentada por B. atrophaeus, os extratos utilizados demonstraram potencial antimicrobiano sobre os demais micro-organismos.