Perfil clonal, resistência antimicrobiana e atividade bactericida do Polipirrol e extrato aquoso de Moringa oleifera em Staphylococcus spp. de leite, ambiente e ordenhadores

• Autor(a) principal: SILVA, José Givanildo da
• Data de Publicação: 2020
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFRPE
• Texto Completo: http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/8473
• topic: Mastite bovina; Staphylococcus; Polipirrol; Atividade antimicrobiana; Moringa oleifera; Atividade bactericida; CIENCIAS AGRARIAS::MEDICINA VETERINARIA

This study aimed to determine the frequency of bovine mastitis caused by Staphylococcus spp. in dairy farms from Pernambuco state, Brazil. Detect mecA and mecC genes responsible for resistance to methicillin, and norA, norB, norC, msrA, mgrA, tet-38 and lmrS genes responsible for multidrug efflux system on Staphylococcus spp. isolates, typify Methicillin-resistant S. aureus (MRSA) strains by Pulsed Field Electrophoresis Gel (PFGE) method, and evaluate the antimicrobial activity of Polypyrrole Nanoparticles (PPy-NPs) and aqueous extract of Moringa oleifera on multidrug efflux system gene carrying Staphylococcus spp. strains. 676 milk samples, 15 swabs from milker’s nostrils and hands, 14 swabs from teat cup and 9 from milking buckets were collected from 5 rural properties (A-E). Initially, the California Mastitis Tests (CMT) was performed, and samples with results higher than ≥ + (one cross) (319 samples) or those positive on the strip cup test (16 samples) were collected for microbiological analysis. Samples were submitted to microbiological test for detection of Staphylococcus spp., molecular technique (PCR) for identification of Staphylococcus aureus and mecA, mecC, norA, norB, norC, msrA, mgrA, tet-38 and lmrS genes. For mecA-MRSA isolates, Minimal Inhibitory Concentration (MIC) was determined and genotyped by Pulsed-Field Gel Electrophoresis (PFGE), and mecC-carrying isolates were submitted to genome sequencing. On isolates carrying multidrug efflux system genes, Minimal Inhibitory Concentration (MIC) and Minimal Bactericidal Concentration (MBC) of PPy-NPs and aqueous extract of Moringa oleifera were determined. MRSA were detected in 1,49% (5/335), 20% (3/15), 6,6% (1/15) and 7,1% (1/14) of milk, nostrils, hands, and teat liners samples respectively. All isolates were susceptible to oxacillin by MIC. By PFGE it was possible to identify VIII pulsotypes (A-H) between MRSA isolates, divided into three major clusters. MecC gene was detected in 4,68% (3/64) isolates of S. aureus of the same strain. By sequencing, this strain presented virulence genes related to exoenzymes, toxins, enterotoxins, multidrug efflux system, antibiotic inactivation genes and plasmid, this strain was attributed to ST 126 and MRSA t605, also nine new proteins related to methicillin resistance were identified. The results obtained impact directly on public health as this is the first study that detects dissemination of multi-resistant Staphylococcus spp. isolates with different clonal profiles in agricultural environment of dairy farms from Pernambuco state, Northeastern of Brazil. It was also comproved the bactericidal activity of aqueous extract of Moringa oleifera and PPy-NPs, being necessary new studies about using these compounds as alternatives for treatment of infections by multidrug resistant Staphylococcus spp.