Antibacterial and antidermatophyte activities of some essential Oils from spices

Abstract

The inhibitory effects of ten essential oil from different spices against the growth of various isolates of bacteria representing Gram-positive (seven isolates) and Gram-negative (four isolates) were studied. Eight antibacterial agents were included for comparative purposes. Results show that essential oils of thyme (Thymus vulgaris L.), cinnamon (Cinnamomum verum Presl (Syn. C. zylanicum Blume) and cardamom (Elettaria cardamum White and Maton) were highly active against both Gram-negative and Gram-positive bacteria. The essential oils of peppermint {Mentha piperita var, officinalis), marjoram (Majorana hortensis L.) and rosemary {Rosmarinus officinalis L.) showed moderate effects against the test bacteria. The essential oils of Chinese cassia {Cinnamomum cassia Presl), clove {Syzygium aromaticum L.) Merr and Perry (Syn. Eugenia caryophyllata Thunb), cumin (Cuminum cyminum L.) and eucalyptus (Eucalyptus globulus L.) had no or little effect against Gram-negative and Gram-positive bacteria. The inhibitory effect of the essential oils against eight different species of dermatophytic fungi were also studied. Thyme and cinnamon oils were highly effective inhibitory agents against all the isolates tested when added at 200 and 500 ppm. Peppermint oil completely inhibited the growth of all the fungi tested at 500 ppm and three isolates when added as 200 ppm. Essential oil of cardamom only inhibited the same three isolates when added at 500 ppm. The other essential oils tested, showed partial inhibition against the growth of the test fungi.