Effect of curcumin and 5-bromoindole-3-carboxyaldehyde on the inhibition of Quorum sensig-dependent virulence factors inPseudomonas aeruginosa

Abstract

AbstractObjetiveTo evaluate the inhibitory effect of Quorum Sensing-dependent virulence factors inPseudomonas aeruginosaby 2 molecules; curcumin and 5-bromoindole-3-carboxyaldehyde.MethodsFor the tests, 3 strains ofP. aeruginosawere used; Pa01, Pa14 and ATCC 27853. The strains were reseeded in LB medium boxes for 12 hours at 37°. ON cultures of each strain were inoculated in LB broth, grown for 24 hours at 37°. Subsequently, new cultures of the strains were inoculated at starting from the ON cultures with an initial O.D 600 nm of approximately 0.0125, the following concentrations of the molecules were evaluated with these cultures: curcumin (1 and 5 μg/ml) and 5-bromoindole-3-carboxyaldehyde (30, 50 and 100 μg/ml). The factors were read virulence with their respective wavelength; protease (595 nm), elastase (495 nm), pyocyanin (520 nm) and alginate (530 nm).Results5-bromoindole-3-carboxyaldehyde significantly inhibited pyocyanin production in Pa01 (92.5% at 100 μg/ml), elastase in Pa01 (79.85% at 100 μg/ml), protease in Pa01 (92.8% at 50 μg/ml), and alginate in ATCC 27853 (76.16% at 100 μg/ml). Curcumin showed substantial inhibition of pyocyanin in ATCC 27853 (100% at 5 μg/ml), elastase in Pa14 (56.19% at 5 μg/ml), protease in Pa01 (87.04% at 5 μg/ml), and alginate in Pa01 (48.26% at 5 μg/ml).ConclusionsCurcumin and 5-bromoindole-3-carboxyaldehyde demonstrated effective inhibition of QS-dependent virulence factors inP. aeruginosa. These findings suggest the potential of these compounds as anti-virulence agents, providing a promising alternative to conventional antibiotics in combatingP. aeruginosainfections.