title: Bioactivity of Variant Molecular Weight Chitosan Against Drug-Resistant Bacteria Isolated from Human Wounds.
abstract: Chitosan available from crab shells is usually of high molecular weight which may result in reduced efficiency for its antibacterial activity. One of the techniques for improving chitosan antibacterial efficiency is reducing its molecular weight. The irradiation of chitosan by gamma radiations is considered to be one of the most effective and widely used methods for improving its antibacterial activity. Chitosan obtained from crab shells was irradiated with gamma radiations at different doses, and effects on chitosan were analyzed by molecular weight determination and Fourier Transform Infrared spectroscopy. Unirradiated and irradiated chitosans were studied for their antibacterial properties against bacterial pathogens, that is, Pseudomonas aeruginosa (SS29), Escherichia coli (SS2, SS9), Proteus mirabilis (SS77), and Staphylococcus aureus (LM15). Studies have shown that irradiation has significantly developed and improved the antibacterial activity of crab shell chitosan. A correlation was found between bacterial metabolites and antibacterial activity by the analysis for 4-hydroxy-2-alkylquinolines and related metabolites of P. aeruginosa (SS29) in the absence and presence of chitosan by liquid chromatography mass spectrometer, exhibiting the suppression of these virulence factors due to chitosan. Antibacterial efficiency of chitosan was found to be molecular weight dependent and applied concentration of the chitosan. The findings suggest on the use of low-molecular weight chitosan as antibacterial agent in pharmaceutical preparations.
authors.affiliation: 1 Jhang-Campus, University of Veterinary and Animal Sciences , Lahore, Pakistan .
authors.forename: Ijaz
authors.initials: I
authors.lastname: Bano
authors.affiliation: 2 Industrial Biotechnology Division, National Institute for Biotechnology and Genetic Engineering , Faisalabad, Pakistan .
authors.forename: Muhammad Afzal
authors.initials: MA
authors.lastname: Ghauri
authors.affiliation: 1 Jhang-Campus, University of Veterinary and Animal Sciences , Lahore, Pakistan .
authors.forename: Muhammad
authors.initials: M
authors.lastname: Arshad
authors.affiliation: 3 Department of Metallurgy and Materials Engineering, Pakistan Institute of Engineering and Applied Sciences , Islamabad, Pakistan .
authors.forename: Tariq
authors.initials: T
authors.lastname: Yasin
authors.affiliation: 1 Jhang-Campus, University of Veterinary and Animal Sciences , Lahore, Pakistan .
authors.forename: Muhammad
authors.initials: M
authors.lastname: Younus
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects*; D048271:Chitosan / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial / Q000187:drug effects*; D006801:Humans; D008826:Microbial Sensitivity Tests; D008970:Molecular Weight; D037521:Virulence Factors / Q000378:metabolism; D014947:Wounds and Injuries / Q000382:microbiology*
chemical_list: D000900:Anti-Bacterial Agents; D037521:Virulence Factors; D048271:Chitosan
keywords: antibacterial activity; chitosan; molecular weight; pathogens; radiations