Antiseptic Effect of Volatile Fatty Acid Monoglycerides

Part II Antiseptic effect on wild yeast, Aspergillus oryzae, and Bacillus subtilis

Abstract

Of monopropionin, monobutyrin, monocaproin, monocaprylin, monocrotonin, and monosorbin examined, monocaprylin had the most antiseptic effect on A. oryzae, B. subtilis, and a strain of wild yeast separated from putrid fermented milk. Antiseptic effect of these monoglycerides decreased with the decrease in carbon number of composing fatty acids. These monoglycerides showed less effect than their corresponding fatty acids, respectively, except that monocaprylin was more effective than caprylic acid. Such tendency seemed to be in close negative correlation with their surface activity with the exception of monopropionin. These monoglycerides were more effective in the medium of lower pH, especially in the case of B. subtilis. The susceptibility of B. subtilis to these monoglycerides and free fatty acids composing them was greater than the other two. Aceton-acetals of monocaprylin and monosorbin showed the effect similar to those of caprylic and sorbic acid, respectively. The antiseptic mechanism of the monoglycerides was also discussed.