title: Chitosan-Based Film of Tyrothricin for Enhanced Antimicrobial Activity against Common Skin Pathogens Including Staphylococcus aureus.
abstract: Chitosan-based film-forming gel is regarded as a promising vehicle for topical delivery of antimicrobial agents to skin wounds, since it protects from microbial infection and the cationic polymer itself possesses antibacterial activity. In this study, possible synergistic interaction against common skin pathogens between the cationic polymer and tyrothricin (TRC), a cyclic polypeptide antibiotic, was investigated, by determining the concentration to inhibit 90% of bacterial isolates (MIC). The addition of the polysaccharide to TRC dramatically reduced the MIC values of TRC by 1/33 and 1/4 against both methicillin-resistant and methicillinsusceptible Staphylococcus aureus, respectively. The synergism of TRC and chitosan combination against both strains was demonstrated by the checkerboard method, with a fractional inhibitory concentration index below 0.5. Moreover, co-treatment of TRC and chitosan exhibited antibacterial activity against Pseudomonas aeruginosa, due to the antibacterial activity of chitosan, whereas TRC itself did not inhibit the gram-negative bacterial growth. These findings suggested that the use of chitosan-based film for topical delivery of TRC could be an alternative to improve TRC antimicrobial activity against strains that are abundant in skin wounds.
authors.affiliation: Dong-A ST Research Institute, Pharmaceutical Product Research Laboratories, Yongin 17073, Republic of Korea.
authors.forename: Sang Duk
authors.initials: SD
authors.lastname: Han
authors.affiliation: Dong-A ST Research Institute, Pharmaceutical Product Research Laboratories, Yongin 17073, Republic of Korea.
authors.forename: Hyun Jung
authors.initials: HJ
authors.lastname: Sung
authors.affiliation: Dong-A ST Research Institute, Pharmaceutical Product Research Laboratories, Yongin 17073, Republic of Korea.
authors.forename: Ga Hyeon
authors.initials: GH
authors.lastname: Lee
authors.affiliation: Dong-A ST Research Institute, Pharmaceutical Product Research Laboratories, Yongin 17073, Republic of Korea.
authors.forename: Joon-Ho
authors.initials: JH
authors.lastname: Jun
authors.affiliation: Dong-A ST Research Institute, Pharmaceutical Product Research Laboratories, Yongin 17073, Republic of Korea.
authors.forename: Miwon
authors.initials: M
authors.lastname: Son
authors.affiliation: College of Pharmacy, Dankook University, Cheonan 31116, Republic of Korea.
authors.forename: Myung Joo
authors.initials: MJ
authors.lastname: Kang
mesh_terms: D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000737:chemistry; D048271:Chitosan / Q000008:administration & dosage* / Q000737:chemistry*; D004338:Drug Combinations; D004357:Drug Synergism; D005782:Gels / Q000008:administration & dosage / Q000737:chemistry; D006801:Humans; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects; D008826:Microbial Sensitivity Tests / Q000379:methods; D050296:Microbial Viability / Q000187:drug effects; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D012867:Skin / Q000382:microbiology*; D013207:Staphylococcal Skin Infections / Q000188:drug therapy; D013211:Staphylococcus aureus / Q000187:drug effects*; D014449:Tyrothricin / Q000008:administration & dosage* / Q000737:chemistry*
chemical_list: D000900:Anti-Bacterial Agents; D004338:Drug Combinations; D005782:Gels; D014449:Tyrothricin; D048271:Chitosan
keywords: Staphylococcus aureus; Tyrothricin; antimicrobial activity; chitosan; skin infection