Effect of curcumin on biofilm formation and motilities of <i>Pseudomonas aeruginosa</i> clinical isolates

Drug resistant Pseudomonas aeruginosa is known to produce biofilms in hospital and food industrial environments. Among the different types of P. aeruginosa motilities, swarming and twitching is involved in biofilm formation. Curcumin, a common food additive was used to determine the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), the inhibitory effect on biofilm formation and motilities of P. aeruginosa. Muller Hinton agar with curcumin were used to study the MIC and MBC of 80 clinical P. aeruginosa isolates. The effect of curcumin on swarming, swimming, and twitching motility was determined by using swarm, swim, and twitch plates and on biofilm by microtiter plate method. The study revealed that curcumin had antibacterial effect on 69 isolates, and only 11 strains were resistant to curcumin at 25 mg/dl. Subinhibitory concentrations of curcumin suppressed motility and biofilm production (p < .001). Thus, Curcumin can be an alternative to currently available antipseudomonal agent to inhibit motility and biofilm.