Determination of antimicrobial properties of picaridin and DEET against a broad range of microorganisms.

Insect repellents are topically applied to the skin and clothing of human and pet to keep flies, mosquitoes, and ticks away. Two important repellents, N,N-diethyl-meta-toluamide (DEET) and Picaridin, have been widely used since their discovery. Although repellency and toxicological effects of DEET and Picaridin on human being and insects are well documented without understanding molecular mechanisms, there have been no attempts to study their effects on microorganisms up to now. In the current study, DEET and Picaridin have been investigated for their antimicrobial characteristics against a broad range of microorganisms including bacteria, yeast, and fungi for the first time. They exhibited considerable antibacterial, anticandidal and antifungal properties. Even though bacteria was found to be more sensitive to Picaridin, yeast and fungi were more susceptible to DEET. Antimicrobial properties of these two repellents will increase the usage and application areas of the products containing DEET and Picaridin.