Quantification of Bacterial Pigments

The bacterial culture grown overnight was diluted to 1 × 10⁵ CFU/mL in a TSB medium, transferred to a 24-well plate (Sarstedt, Nümbrecht, Germany), and incubated at 37 °C for 48 h. After incubation, each bacterial suspension was collected in an Eppendorf tube and centrifuged at 10,000 RPM. The obtained supernatants were transferred to a transparent 96-well plate (for pyocyanin measurement) and a black 96-well plate (for pyoverdine measurement). The absorbance for pyocyanin was measured using a Varioskan Lux microplate reader (Thermo Fisher Scientific Inc., Waltham, MA, USA) at λ = 686 nm, and the fluorescence for pyoverdine at λ = 395 nm (excitation) and λ = 460 nm (emission). Five repetitions were made for each experiment option [21 (link)]. For the statistical analysis, the one-way ANOVA (the Tukey test) for independent groups was used (p-values < 0.001 were regarded as significant).