Laboratory assessment of inhibitory properties of monolaurin against Staphylococcus aureus in beef

Monolaurin is one of the main triglycerol monoesters of acid lauric, which has inhibitory effect on broad spectrum of bacteria. In order to enhance the antibacterial effect of monolaurin, some chelating agents such as EDTA and acidifiers are used. The aim of this study was to evaluate the inhibitory effects of monolaurin on Staphylococcus aureus and the effects of organic materials on reduction of monolaurin inhibitory effect in meat products. At first, minimum inhibitory concentration (MIC) of monolaurin alone and in combination with EDTA and lactic acid on staphylococcus in nutrient broth was investigated, then the inhibitory effect of monolaurin alone on bacteria was studied in sterile meat along with antibacterial effect of monolaurin and EDTA on unsterile meat. Data were analyzed using Variance test (ANOVA). MIC for monolaurin, monolaurin and EDTA and monolaurin and lactic acid were 32,16 and 8 μg/ml, respectively. The inhibitory effect of monolaurin alone on bacteria in sterile meat reduced significantly. Combination with lactic acid increased the effect of monolaurin on bacteria in sterile meat, but,monolaurin in combination of EDTA in unsterile meat did not show significant antibacterial effect. based on these findings, monolaurin can be used as food preservative in order to prevent food spoilage. The organic materials in the meat product could prevent the antibacterial effect of monolaurin. In addition chelating agents could enhance the antibacterial effect of monolaurin.