• Journal of Microbiology and Biotechnology
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• 제26권4호
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• pp.784-789
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• 2016

We evaluated the synergistic antibacterial effect in combination with the chitosan-ferulic acid conjugate (CFA) and β-lactam antibiotics, such as ampicillin, penicillin, and oxacillin, against methicillin-resistant Staphylococcus aureus (MRSA) using fractional inhibitory concentration (FIC) indices. CFA clearly reversed the antibacterial activity of ampicillin, penicillin, and oxacillin against MRSA in the combination mode. Among these antibiotics, the combination of oxacillin-CFA resulted in a ΣFIC_min range of 0.250 and ΣFIC_max of 0.563, suggesting that the oxacillin-CFA combination resulted in an antibacterial synergy effect against MRSA. In addition, we determined that CFA inhibited the mRNA expression of gene mecA and the production of PBP2a, which is a key determinant for β-lactam antibiotic resistance, in a dose-dependent manner. Thus, the results obtained in this study supported the idea on the antibacterial action mechanism that oxacillin will restore the antibacterial activity against MRSA through the suppression of PBP2a production by CFA.

• 한국수산과학회지
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• 제49권5호
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• pp.589-593
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• 2016

Propionibacterium acnes infection in skin tissue often causes acne vulgaris, commonly characterized by inflammatory papules, pustules, and nodules. Chitosan and its derivatives possess strong anti-inflammatory effects. In this study, the anti-inflammatory activity of chitosan-phytochemical conjugates on P. acnes-infected human skin keratinocytes (HaCaT) was evaluated. We designed a model of P. acnes-induced inflammation in viable HaCaT cells. Nitric oxide (NO), an inflammatory marker, was successfully elevated by P. acnes infection in HaCaT cells in a dose-dependent manner. Furthermore, the levels of NO were reduced by treatment with chitosan-phytochemical conjugates (chitosan-caffeic acid, -ferulic acid and -sinapic acid) in a dose-dependent manner. Among these conjugates, chitosan-caffeic acid exhibited the strongest NO suppression in HaCaT cells infected with P. acnes. The results obtained in this study suggest that chitosan-phytochemical conjugates could be used as a potential therapeutic agent against acne vulgaris.