Activity of Cloves, Cinnamon and Thyme Essential Oils Against Some Oral Bacteria

Background: Gastronomic natural flavors and spices have been used as both flavoring agents and preservatives in food preparation for many years. They have also been utilized in medical field for their biological properties shown in previous studies. Objective: The study aimed to evaluate the inhibitory effect of the oil extracts from Cloves, Thyme, and Cinnamon compared with ampicillin on some oral bacteria (Staphylococcus aureus, Streptococcus mutans, Lactobacillus spp., Pseudomonas aeruginosa, and Proteus spp.). Method: Evaluation of the antibacterial effect of herbal and spices essential oil was performed using Agar well diffusion test. Its effect was assessed against oral bacteria, which diagnosed in laboratory by culturing on enriched and selective media and by biochemical test. Results: High inhibitory effect of cinnamon, clove against some Gram positive and Gram negative isolated oral bacteria (Staphylococcus aureus, Streptococcus mutans, Lactobacillus spp., Pseudomonas aeroginosa, and Proteus spp. comparing with ampicillin. While thyme essential oil shows inhibitory effect for the bacterial isolates except for Pseudomonas aeroginosa but less than the inhibitory effects of other essential oils and ampicillin. For Psedomonas aeruginosa result shows the bacteria have resistance to ampicillin and Thyme essential oil while both cloves and cinnamon have antibacterial effect. Conclusions: Cloves, thyme and cinnamon essential oil have a wide antimicrobial activity against some oral bacteria, both cinnamon and cloves essential oils recorded superior antibacterial activity than ampicillin for (Proteus spp and lactobacillus), competence action with ampicillin for Staphylococcus aureus and Streptococcus mutans and novel antibacterial action against Pseudomonas aeroginosa which resist to ampicillin which may be a promising antibacterial management approach and resist development of antibiotic resistance strain if used instead than the antibiotic. Also, suggestion for using these oils orally may provide a degree of protection in oral cavity against some oral pathogens.