Antibiotics have done much good for many people in the last 100 years or so but not without cost. They are becoming highly overused and this has led and is leading to antibiotic resistance.
There is an ever increasing occurrence of antibiotic resistant strains of bacterial pathogens that is creating a major threat to public health and has become a concern of worldwide health authorities. Some of the most common antibiotic resistant pathogens include Methicillin-resistant Staphylococcus aureus (MRSA) and vanomycin-resistant enterocci (VRE) (Mulynaning, Sporer, Reichling, & Wink, 2011). Few will deny an urgent need to find alternative antimicrobial agents to treat the ever increasing list of drug resistant microbial strains. This presents a prime opportunity for alternative medicine to rise to the occasion and prove it has something to offer that will gain the respect of conventional medicine.
Essential oils have been in use for thousands of years longer than any conventional medication and have been prized for centuries for their healing and preserving properties. Plant oils are indeed essential to the protection of the plant and work as antifungals, antivirals, insecticides and antibacterials.
There are three basic methods of utilizing essential oils for therapeutic results. The most common method is inhalation of the oil, but oils are also used topically, or transdermally, and internally. Essential oils can also be used in suppository form rectally or vaginally depending upon the goal of treatment and oil used. For antibiotic uses, the oils are typically diffused into the air or applied topically to the skin. Certain oils can also be taken internally in a capsule for internal antibiotic use but caution must be exercised and the purity of the oil should be considered.
When an essential oil molecule is inhaled through the nasal passages, the odor molecule is sensed by the olfactory cells of the olfactory epithelium. The olfactory cells have hair like structures called cilia that extend from dendrites in the nasal cavity. These cilia have receptors that bind to specific odor molecules and when this binding occurs, the olfactory cells send a signal through the cribriform bone plate at the roof of the nasal cavity to the olfactory bulb. The olfactory bulb then transmits the signal along the lateral olfactory tract to the corresponding brain regions including the amygdala. Due to the olfactory system being so closely connected to the limbic system “essential oils have profound physiological and psychological effects ” (Modern Essentials, 2012, p. 32).
When the essential oils are applied topically to the skin, the molecules are absorbed into the bloodstream and carried throughout the tissues, organs and muscle cells. The byproducts of the oils are excreted through the skin, kidneys, bladder, lungs and large intestine, the same as other food is processed by the body(Rose, 2007). Transdermal absorption of essential oils has the possibility of producing central nervous system effects (Herz, 2009).
One phenomenal study done at Wythenshawe hospital in England diffused a blend of East Indian lemongrass and sweet scented geranium essential oils into the air. An airborne bacterium, including MRSA was reduced by 89% after being diffused for 15 hours. The vaporizer diffusing these oils continued to operate for 9 months in the hospital’s burn unit and resulted in the disappearance of MRSA infections along with a dramatic decrease in other infections. The control portion of this studied removed the essential oils for the last 2 months of the study and this resulted in a MRSA outbreak (Stafford, 2011).
Many different essential oils have some of the same chemical constituents in their biological makeup and those contained in this report do not reflect a complete listing of essential oils. A Canadian- based research study evaluated twenty eight essential oils to determine antibacterial properties, and the most effective essential oils in this study were thyme essential oils that had significant levels of thymol and carvacrol (Tisserand, 2012). Four different lavender essential oils, Lavandula angustifolia, Lavandula latifolia, Lavandula stoechas and Lavendual luisieri inhibited the growth of MSSA and MRSA by direct contact (Roller, et al., 2009).
The antimicrobial properties of melaleuca, peppermint and sage have proven to be very effective against anaerobic oral bacteria (Hill, Evans & Veness, 1997). Additionally, the oils of, “ cinnamon, thyme, lemon, lemon balm (Melissa officinalis, Lamiaceae), lemongrass, sage, clary sage (S. sclarea, Lamiaceae), and eucalyptus essential oils have been found to be active against several bacterial strains, including MRSA, S. aureus, E. coli, S. epidermidis, Candida krusei, S. pneumoniae, Haemophilus influenza, and Moraxella catarrhalis (Stafford, 2010, p. 7).
Growing conditions of the plants have a direct relation to the strength and quality of the chemical components of the essential oils. According to Hill et al. (1997), significant differences were noted in oil composition based upon level and duration of moisture stress. Furthermore, if an oil is considered for internal use it should be therapeutic grade and labeled safe for internal use.
Essential oils have many different potential methods of overcoming microbial invaders. Essential oils have the ability to act as pro-oxidants on the protein and DNA production of reactive oxygen species bacteria and can damage the cellular and organelle membranes. Bacteria membrane permeability is affected by ion loss with subsequent membrane potential reduction and proton pump collapse along with ATP pool depletion. Other mechanisms of bacterial death that can be initiated by essential oils include the ability to coagulate the cytoplasm of the bacteria and cause damage to the lipids, proteins and cell wall leading to macromolecule leakage and cell lysis. Additionally, the fluidity of the membrane can change causing cellular leakage (Bakkali et al., 2008).
References:
Hill, P., Evans, C., Veness, R. (1997). Antimicrobial action of essential oils: the effect of dimethylsulphoxide on the activity of cinnamon oil. Letters in Applied Microbiology, 24, 269-275
Herz, R. (2009). Aromatherapy facts and fictions: A scientific analysis of olfactory effects on mood, physiology and behavior, International Journal of Neuroscience 119, 263-290.