Inhibition of biofilm formation

The effect of TS against biofilm formation was measured using an XTT reduction assay and microscopic observation as previously described (20). 100 µL YEM30 (wild type strain), CCF3 (flo8/flo8 mutant) and HLY3426 (flo8/flo8 + FLO8 mutant) (16) cell suspensions (1×10⁶ cells/mL in RPMI1640 medium or RPMI1640 plus 5% FBS medium) containing various doses of TS (0, 32, 64 and 128 µg/mL) were seeded into a 96-well flat-bottom plate. The plate was incubated at 37 °C for 24 h in static culture. After three washes with sterile PBS (0.01 M, pH 7.2), biofilm formation was measured with an XTT Cell Proliferation Assay Kit (BestBio, Shanghai, China) according to the provided protocol and observed under an Olympus microscope in the bright field mode.