Comparative antibacterial effects of garlic and cumin essential oils

ABSTRACT

The inhibitory effect of garlic and cumin essential oils on some pathogenic bacteria namely, B. cereus, Staph. aureus, E. coli and Ps. aeruginosa, was investigated. Different concentrations of each oil [0-160 mul/100 ml] were added to the growth medium, then incubated at 37C/48 hr. The extent of bacterial growth was determined at different intervals by measuring the optical density of the bacterial cultures broth at 580 nm. The obtained results revealed that, garlic oil was more active against the tested bacteria compared with cumin oil. Also, B. cereus was the most sensitive one to both oils followed by Staph. Aureus. Complete inhibition was attained with oils concentration 50 mul/100 ml broth. The growth of E. Coli and Ps. aeruginosa were reduced by adding either garlic or cumin oil; the effect was proportional with the concentration of used oil. Complete inhibition was not attained with the use of 120 and 160 mul/100 ml of garlic and cumin oils, respectively, therefore, more concentration of these oils are needed for complete inhibition of E. Coli and Ps. aeruginosa