is a major biofilm-forming, opportunistic pathogen. Tolerance to antimicrobial agents due to biofilm formation may lead to the emergence of antimicrobial-resistant bacterial strains. Thus, adjunctive agents that can inhibit biofilm formation are necessary to enhance the therapeutic efficacy of antimicrobial agents. In this study, we evaluated the anti-biofilm formation activity of selected Chinese herbal medicines and nutraceuticals, which are commercially available in Japan. Among the eight agents evaluated for their potential to inhibit biofilm formation, Eiekikaryu S, Iribakuga and Hyakujunro significantly reduced biofilm formation ( <0.05) without inhibiting bacterial growth. Additionally, the expression of biofilm-associated genes (, and ) in was significantly suppressed by Eiekikaryu S, Iribakuga and Hyakujunro ( <0.001). Our findings indicate that some Chinese herbal medicines and nutraceuticals can be potential adjunctive agents for antimicrobial therapy against .

This study was supported by the:
  • Japan Society for the Promotion of Science (Award JP18H00370)
    • Principle Award Recipient: NorihisaNoguchi
  • This is an open-access article distributed under the terms of the Creative Commons Attribution License.

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