Enterococcus spp. isolado de vegetais: perfil de suscetibilidade a antimicrobianos e formação de biofilme

Abstract

The e enterococci are Gram-positive cocci that belong to the group of lactic acid bacteria (LAB). They can be isolated from plants, soil, water, food and the digestive tract of humans and other mammals. Some strains are potentially pathogenic and resistant to antibiotics, especially vancomycin and other clinically important antibiotics. Due to this scenario, foods are being suggested as reservoirs enterococci resistant to antimicrobials. However, there are few studies that analyze the presence of this organism in food vegetable. Therefore, this study aimed to isolate and identifyenterococci from samples of leafy vegetables, legumen and roots, and verify their susceptibility to antimicrobial and biofilm formation. Isolates were identified to genus / species by polymerase chain reaction (PCR) using the primers of the main species.The antimicrobial susceptibility was determined by disk diffusion method and thepresence of ermB genes, aac (6 '), tetL, tetM, vanA and vanB by PCR. Biofilm formation ability was determined in vitro by the total biomass. 85 were obtainedEnterococcus distributed in 62% of samples. The species identified were:Enterococcus casseliflavus/flavescens, Enterococcus columbae, Enterococcus faecium, Enterococcus mundtii and Enterococcus avium. From the isolates showed 64% phenotypic resistance to all tested antibiotics, especially vancomycin, erythromycin, teicoplanin, ampicillin and penicillin. Most species had at least one isolate resistant to vancomycin. 61% of resistant isolates showed multidrug resistance. The genes were detected: tet M (15%), tetL (8%), vanA (5%), vanB (4%)and aac-(6 ') (2%). All isolates were able to form biofilm, where 27 % were classifiedas weak biofilm producer, 60 % moderate and 13 % stronger. Isolated producers of moderate biofilm were the ones who were resistant to vancomycin, teicoplanin, erythromycin and penillicin. According to these results, the vegetables can act as a reservoir of enterococci resistant to several antibiotics of clinical importance, especially vancomycin. This represents a risk to public health since vancomycin is the last therapeutic option for the treatment of severe enterococcal infections.