ENHANCEMENT OF ANTIMICROBIAL ACTIVITIES BY THE FOOD-GRADE MONOLAURIN MICROEMULSION SYSTEM

Monolaurin (M) is a potential natural antimicrobial agent used in foods. It is considered to have an antimicrobial activity against gram-positive bacteria. A monolaurin microemulsion (MME) system inhibited the growth of Bacillus subtilis, Escherichia coli, Aspergillus niger and Penicillium digitatum. Microemulsions (MEs) are transparent, isotropic solutions of oil, surfactant, cosurfactant and water, which are thermodynamically stable and have been much studied in terms of pharmaceutical and cosmetic applications. The growth of B. subtilis was inhibited more strongly by MME than by M. A similar pattern was observed for E. coli, A. niger and P. digitatum, although an enhanced inhibition by MME system over that obtained in comparable M alone was not observed.