Avaliação in vitro da atividade antimicrobiana de extratos vegetais sobre microrganismos relacionados à lesão de mucosite oral

Abstract

Oral mucositis is the most common oral complication in patients undergoing chemotherapy or radiotherapy. Several microorganisms may be present in this oral lesion which complicates treatment. Antimicrobial property of plants has been studied in order to confirm its action and potential to control infectious diseases, mainly due to raise of antimicrobial known resistant microorganisms. Study aimed to observe inhibitory action of plant extracts from Arrabidaea chica, Bryophyllum calycinum, Mansoa alliacea, Azadirachta indica, Senna alata, Vatairea guianensis, Vismia guianensis, Ananas erectifolius, Psidium guajava, Euterpe oleracea and Symphonia globulifera on strains of microorganisms usually involved in lesions of oral mucositis, Streptococcus mitis (ATCC 903), Streptococcus sanguis (ATCC 10557), Streptococcus mutans (ATCC 25175), Staphylococcus aureus (ATCC 6538), Pseudomonas aeruginosa (ATCC 9027), Candida albicans (ATCC 40175), Candida krusei (ATCC 40147), and Candida parapsilosis (ATCC 40038). The evaluation of antimicrobial activity and determination of minimum inhibitory concentration (MIC) were carried out using disk diffusion method on a solid medium. The raw extracts of plants were tested at concentrations of 500, 250, 125, 62.5, 31.25, and 15.62 mg/mL using dimethyl sulfoxide (DMSO) as solvent. Anani and pirarucu extracts have presented the widest spectrum of action, inhibiting growth of seven microorganisms among the eight tested. The lowest MIC was obtained from anani, lacre, and mata pasto extracts. Anani extract was the most active and has demonstrated good antimicrobial activity (MIC below 100 mg / mL) against seven microorganisms (S. aureus, C. albicans, C. krusei, C. parapsilosis, S. mitis. S. sanguis, and S. mutans), showing inactivity only to P. aeruginosa. Lacre extract has shown good activity against five microorganisms. Faveira extract has shown good activity against S. aureus, S. mitis, and C. albicans while P. aeruginosa was the most resistant microorganism showing susceptibility only to pariri and pirarucu extracts. Among evaluated extracts, only curuauá have shown no activity on any microorganisms. The results have demonstrated antimicrobial properties of plant products tested. However, further approaches shall clarify mechanisms of action and possible interactions with antimicrobial drugs, aiming the treatment of infectious diseases.