Asian J Beauty Cosmetol. 2015; 13(2): 213-220.

Effect of Phenoxyethanol and Alkane Diol Mixture on the Antimicrobial Activity and Antiseptic Ability in Cosmetics

The preservatives traditionally used in the cosmetics such as parabens are regarded as a component to be eliminated because of their harmful properties. Nonetheless, the addition of anti-microbial agents is unavoidable to prevent the microbial contamination. Alkane diols, one of the widely used moisturizing components of cosmetics, are now used as the alternative of anti-microbial agents. In this work, alkane diols such as 1,2-pentanediol, 1,2-hexanediol, 1,2-octanediol and phenoxyethanol were tested to determine their anti-microbial activity and the possibility to be used as the preservatives in the cosmetics. The inhibition of microbial growth with single alkane diol was not strong enough except the 1,2-octanediol, which could weakly inhibit the four tested microorganisms including E. coli, P. aeruginosa, S. aureus, C. albicans. For this reason, each alkane diol and phenoxyethanol combination is not suitable for the cosmetic preservatives. On the other hand, the combined three chemicals, 1,2-hexanediol (0.3%), 1,2-octanediol (0.3%) and phenoxyethanol (0.3%) could successfully inhibit the growth of the four microorganisms and this was confirmed by applying them to the cosmetic emulsion and showing that a 3 log reduction of microorganism was possible. On the basis of these results, the combination of alkane diols with phenoxyethanol could be used as a good alternative of cosmetic preservatives.

Keywords : Phenoxyethanol, Alkane diols, Microorganisms, Anti-microbial activity, Antiseptic ability in cosmetics