ANTIMICROBIAL AND CELL VIABILITY MEASUREMENT OF CHITOSAN NANOPARTICLES TO BE APPLIED AS THERAPY IN BOVINE MASTITIS

ORELLANO MS; BOHL LP; ISAAC P; BRESER ML; FALCONE D; PORPORATTO C

Congreso; LXI REUNIÓN ANUAL DE LA SOCIEDAD ARGENTINA DE INVESTIGACIÓN CLÍNICA (SAIC); 2016

Staphylococcus is the genus commonly isolated from bovinemastitis in many countries, which can express several virulencefactors, including biofilm formation associated with persistent infections.The difficulty in eradication and the increasing concerns onantibiotics usages underscore the interest in developing new toolsto control staphylococcal mastitis. The use of nanomaterials inmedicine has enabled the development of more effective therapies.The purpose of this study was to evaluate the antimicrobial activityand anti-biofilm capacity of chitosan nanoparticles (ChNP) againstbovine mastitis isolates, as well as their cytotoxic effect on bovinemammary epithelial cells (MAC-T), macrophages (BoMAC) andkidney cells (MDBK). ChNP were obtained using reverse micelles(RM) as nanoreactors and prepared by cross-linking reaction ofglutaraldehyde and native Ch inside of n-heptane/sodium 1,4-bis-2ethylhexylsulfosuccinate (AOT)/water. ChNP were characterizedby dynamic light scattering showed a size of 134nm. Minimuminhibitory (MIC) and bactericidal (MBC) concentrations of ChNPwere determined against S. aureus (29313 and V329) and S.xylosus (1007) strains, and the biofilm biomass and cell viabilitywere quantified spectrophotometrically after staining with crystalviolet and MTT. The results show that ChNP has lower MIC andMBC values and stronger ability to inhibit biofilm formation of thebacteria tested than Ch (200 vs 1600 µg/ml; p