Baicalein of <i>Scutellaria baicalensis</i> inhibits <i>Mycobacterium abscessus</i> biofilm formation to restore the antibiotics susceptibility

<i>Mycobacterium abscessus</i> is resistant to traditional anti-TB medications and most currently available antibiotics, its strong biofilm formation may contribute to the resistance and make the situation even worse. In this study, <i>Scutellaria baicalensis</i> extract significantly inhibited the planktonic growth as well as the biofilm formation of <i>M. abscessus</i>. Baicalein, the principal active element in <i>S. baicalensis</i> extract, inhibited the biofilm formation instead of the planktonic growth and reduced extracellular matrix lipids in <i>M. abscessus</i> biofilm. The synergistic effects of baicalein in combination with clinical drugs were investigated, the baicalein effectively restored the susceptibility of <i>M. abscessus</i> to the investigated drugs in the biofilm growth. The transcriptome analysis revealed that 98 genes were upregulated and 19 genes were downregulated after baicalein treatment, genes involved in the fatty acid synthesis pathway were validated by RT-qPCR. Therefore, the extract of <i>S. baicalensis</i> and its monomer baicalein might serve as potential innovative adjuvant agents for the prevention and treatment of <i>M. abscessus</i> biofilm formation in chronic infections.