STUDIES ON THE EFFECT OF SOME MEDICINAL PLANTS ON GROWTH AND ACTIVITY OF BACTERIA USED IN FOOD PROCESSING

Abstract

The present study was conducted to evaluate and to compare the antimicrobial activity of clove (Syzygium aromaticum) and thyme (Thymus vulgaris) ethanolic extracts. Different concentrations of ethanolic extracts were prepared and antimicrobial activity was determined against some bacterial, yeast and mold strains. The antimicrobial activity of examined extracts at different concentrations was determined against different cell population of tested strains and expressed as diameter of inhibition zone. Results showed that all clove and thyme ethanolic extracts were markedly inhibited the growth of all tested strains, however, the inhibition effect was differed with regard to the concentration of ethanolic extract as well as the type of tested microorganism. Generally, clove ethanolic extract had stronger antimicrobial activity rather than that of thyme ethanolic extract. Subsequently, clove and thyme are an extremely strong antimicrobial agent with use full potential applications in food processing as a natural safe instead of synthetic antimicrobial agents.