Chitosan disrupts biofilm formation and promotes biofilm eradication in Staphylococcus species isolated from bovine mastitis

• Published in: International journal of biological macromolecules 2019-04, Vol.126, p.60-67
• Main Authors: Felipe, Verónica, Breser, María Laura, Bohl, Luciana Paola, Rodrigues da Silva, Elizabete, Morgante, Carolina Andrea, Correa, Silvia Graciela, Porporatto, Carina
• Format: Article
• Language: English
• Subjects: Antibacterial effects; Biofilm; Bovine mastitis; Chitosan; Staphylococcal infection
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/j.ijbiomac.2018.12.159

Staphylococci are the main pathogens associated with hard-to-control intramammary infections in dairy cattle, and bacterial biofilms are suspected to be responsible for the antimicrobial resistance and persistence of this disease. Biofilms have the ability to resist to higher levels of antibiotics and reduce their efficacy. It is thus necessary to develop strategies targeted to bacterial biofilm infections. Chitosan is a polysaccharide with a proven broad spectrum of antimicrobial activity against fungi and bacteria. The aim of this study was assess the effect of low molecular weight (LMW) chitosan against biofilm hyperproducer Staphylococcus spp. (S. aureus and S. xylosus) strains usually involved in chronic bovine mastitis, and to test their efficacy in biofilm formation and eradication. The results obtained showed that LMW chitosan is able to inhibit S. aureus and S. xylosus planktonic growth in a dose-dependent manner and reduce bacterial viability. LMW chitosan inhibits biofilm formation, reduces biofilm viability and disrupts established biofilm. These results indicate the inhibitory effects of chitosan on biofilm formation, and these effects are observed at lower concentrations for S. xylosus. Our studies show the potential of this biopolymer to be used as an effective antibiofilm agent able to act upon staphylococcal infections. •LMW chitosan inhibits staphylococci planktonic growth in a dose-dependent manner.•The antibacterial activity of chitosan was higher against S. xylosus than S. aureus.•LMW chitosan inhibits staphylococci biofilm formation and disrupt biofilm structure.•LMW chitosan decreases the viability of planktonic and biofilm bacteria.•LMW chitosan could be an effective anti-biofilm strategy for mastitis treatment.