FIG. 3.

Effect of serial dilutions of an authentic standard of catechin on violacein (A) and pyocyanin (B) production in C. violaceum CV026 and P. aeruginosa PAO1, respectively. (C and D) Growth of both bacteria assessed at 600 nm. Violacein and pyocyanin were extracted as described in Materials and Methods and quantified by reading the OD values of the solution at 575 nm (A) and 380 nm (B), respectively. DMSO-supplied cultures were used as controls. The statistical significance of each test (n = 4) was evaluated by conducting Student t tests, and a P value of ≤0.01 was considered significant. ***, Data that are statistically different (P ≤ 0.01).