Antibacterial Activities of Thymus Denaensis, Jaft and Hydro-Alcoholic Extract of Green hull Pistacia Atlantica on Listeria Monocytogenes

Listeriosis is mainly caused by consuming unpasteurized dairy products, especially soft cheese which is contaminated with listeria monocytogenes in people with a damaged immune system. The purpose of this study was to evaluate the possibility of using natural preservatives to control the growth of Listeria monocytogenes in dairy products. In the present experimental study, plants (Thymus denaensis, Jaft and green hull Pistacia atlantica) were collected from the mountains of Kohgiloyeh & Boyerahmad province and their hydroaloholic extract were prepared. Antibacterial activities, MIC and MBC, were determined by disc diffusion and microwell dilution methods. The Ampicilin disk (10µg) was used as positive control in disc diffusion. The data were analyzed by the SPSS software using One-way ANOVA. The most anti-bacterial activities were found with hydroalcoholic extracts of Jaft and green hull Pistacia atlantica. Inhibition zone for the Jaft concentration was 32 mg/ml which was equal to the ampicillin disk. The minimum inhibitory concentration and minimum bactericidal concentration of Jaft extract were 125 and 250 μg/ml respectively. Based on the results of current study, hydroalcoholic extract of Jaft might be a suitable candidate to be used as a preservative in the food industry which is able to prevent the growth of Listeria monocytogenes.