The effects of essential oils, extracts and powder of Satureja bachtiarica bung on the bacterial growth of Staphylococcus aureus in cream cheese

Abstract

<strong>Background and aims:</strong> <em>Staphylococcus aureus</em> is an important contaminant of milk and dairy products. It can cause a wide range of illnesses including, food poisonings and nosocomial infections. The aim of this study was to compare the antimicrobial effects of the essential oil , aqueous extract and powder of the <em>Satureja bachtiarica</em> on s<em>taphylococcus aureus</em>.<br /><strong>Methods:</strong> <em>Satureja bachtiarica</em> was collected from the heights of the province of Chaharmahal va Bakhtiari and its extract and essential oil were collected. The bacteria staphylococcus <em>aureus </em>was obtained from the Iranian Research Organization for Science and Technology. The bacterium was inoculated in equal amounts to specimens of cream cheese; afterward different concentrations of the essential oil , aqueous extract, and herbal powder were produced and inoculated in in equal amounts to the cream cheese specimens; subsequently, the specimens were checked 20, 40 and 60 days after inoculation. In the end, the microbial activity of the essential oil , aqueous extract and herbal powder were reported according to mg/ml.<br /><strong>Results:</strong> The minimum growth of the bacteria <em>staphylococcus aureus</em> was observed in the 1000 milligram concentrations of essential oils and 125 mg of the aqueous extract and 125 mg of powder of the plant. At all the concentrations tested the pH changes in the fortieth day, and the changes in the rigidity of the cream cheese specimens were significant as well. At some of the concentrations of the aqueous extract and some concentrations of the herbal powder the changes in the texture of the cream cheeses, comparing to the controls, were significant.<br /><strong>Conclusion:</strong> The essential oil , aqueous extract and powder of the <em>Satureja bachtiarica</em> have a great inhibiting effect on the growth of the bacterium <em>staphylococcus aureus</em>. Thus, it can be used as a natural preservative in foods with high lipid content.