Optically isotropic, thermodynamically and chemically stable microemulsions of antimicrobials comprising of mixtures of N-undecylenoyl glycine, N-capryloyl glycine and 2-phenoxy ethanol for preservation of personal care products are described herein. They offer a broad spectrum of antimicrobial activity by inhibiting the growth of bacteria as well as fungi that can otherwise flourish in personal care products rendering them unsuitable for the use. The personal care products that can be preserved by these microemulsions of antimicrobials are, gels, serums, solutions, lotions, creams, emulsions, wet wipes and the like, containing water in varying amount.