Comparison of antibacterial effects and fumigant toxicity of essential oils extracted from different plants

The chemical composition, antibacterial and insecticidal potential of Anise, Peppermint, Clove, Cinnamon, Pepper, Citronella and Camphor essential oils (EOs) extracted by steam distillation from seven different plant species were investigated. GC MS analysis revealed that terpenes and phenols were the main components of EOs. The different kinds of EOs exerted appreciable antibacterial action against Gram-positive (B. subtilis and S. aureus) as well as Gram-negative (E. coli and S. typhimurium) bacteria. Among EOs, cinnamon EO exhibited the highest antibacterial effect for all the bacterial strains with the lowest MIC ranging from 0.125 to 0.25 mg/mL, the largest inhibition zone and the strongest inhibition of bacterial growth, followed by clove EO. The moderate inhibitory effects were observed for remaining EOs. On the other hand, cinnamon EO, clove EO, and anise EO exhibited significant fumigant toxicity against Sitophilus oryzae at 7.69 mu L/L air concentration after 24 and 48 h exposure. Furthermore, the single component analysis showed the LC50 values of 2.90 for eugenol, 5.45 for cinnamaldehyde, and 5.42 mu L/L air for estragole extracted from selected EOs (clove, cinnamon, anise), respectively. The results will pave a way for utilization of plant derived EOs as natural food preservatives to counteract food spoilage and pest's managements.