In Vitro Synergistic Inhibitory Activity of Natural Alkaloid Berberine Combined with Azithromycin against Alginate Production by Pseudomonas aeruginosa PAO1

Figure 2

Effects of sub-MIC concentrations of BER and AZM on biofilm biomass, EPS, and total protein of PAO1. (a) The established biofilm formation (%) of PAO1 was measured by crystal violet staining at 595 nm post-treatments with different combinations of BER and AZM for 48 h at 37°C. (b) The visual image of biofilm colonized on microplates by crystal violet staining post-treatments with different combinations of BER and AZM for 48 h at 37°C. (c) Evaluations of biofilm EPS post-treatments with different combinations of BER and AZM for 48 h at 37°C. (d) Evaluations of biofilm protein post-treatments with different combinations of BER and AZM for 48 h at 37°C. Note: MIC: Minimum Inhibitory Concentration; BER: berberine; AZM: azithromycin; EPS: extracellular polysaccharide; , ; , ; , ; compared with the control group.

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