In Vitro Antibacterial and Synergistic Effect of Chitosan-Phytochemical Conjugates Against Antibiotic Resistant Fish Pathogenic Bacteria
Chitosan-phytochemical conjugates exhibited significant antibacterial effect with minimum inhibitory concentration (MIC) ranging from 128 to 2048 µg/ml against antibiotic-resistant fish pathogenic bacteria such as Edwardseilla tarda, Vibrio harveyi and Photobacterium damselaewhich were isolated from Korean cultured fish. Furthermore, the MIC values of old-fashioned antibiotics such as erythromycin and oxytertacycline drastically reduced in combination with chitosan-phytochemical conjugates against the fish pathogenic bacteria. The combination of conjugates with erythromycin and oxytetracycline gave median ∑FIC results ranging from 0.281 to 0.625 and 0.312 to 0.625, respectively. This result indicates the synergistic antibacterial effects and an increased susceptibility against the antibiotics.
KeywordsAntibacterial effect Chitosan-phytochemical conjugate Fish pathogenic bacteria Synergy effect
This research was funded by the Marine Biotechnology Program (20150220) funded by the Ministry of Oceans and Fisheries, Republic of Korea. The pathogen for this study was provided by the Gyeongsang National University Hospital Branch of National Culture Collection for pathogens (GNUH-NCCP).
Compliance with Ethical Standards
Conflict of interest
The authors declare that they have no conflict of interest.
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