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An Effective, Safe, and All-Natural Approach Using Essential Oils
An Effective, Safe, and All-Natural Approach Using Essential Oils

Research Articles

Essential Oils Work With Probiotics. They Do Not Harm Healthy Flora.

Effects of Essential oils on Bacteria in the Gut

Gastroenterology Research and Practice
Volume 2012 (2012), Article ID 457150, 6 pages

Review Article

Development of Probiotic Candidate in Combination with Essential Oils from Medicinal Plant and Their Effect on Enteric Pathogens: A Review

Shipradeep,1 Sourish Karmakar,1 Rashmi Sahay Khare,2 Sumedha Ojha,1 Kanika Kundu,2 and Subir Kundu1

1School of Biochemical Engineering, Indian Institute of Technology, Banaras Hindu University, Varanasi 221005, India
2Chemistry Section, MMV, Banaras Hindu University, Varanasi 221005, India

Received 17 March 2012; Revised 4 May 2012; Accepted 12 May 2012

Academic Editor: Antonio Gasbarrini

Copyright © 2012 Sourish Shipradeep et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Medicinal plants and probiotics both have very high potential in terms of their antimicrobial activity against antibiotic-resistant enteric pathogens. The probiotics being enteric microorganism do not have any parasitic effect on human beings. They have been an integral part of daily food for centuries. They have been shown to have health beneficiary properties. The probiotics retard the growth of the microorganisms, while essential oil kills them. Combining the effect of medicinal plant extract and probiotics may be a new approach due to their complementary antimicrobial effects and practically no side effects. The synergistic effect of the essential oil and probiotics will be necessarily higher than using them alone as health product.


The plants have been used in Ayurvedic medicines from ancient times. The extracts from these plants have shown potent antimicrobial effect. Recently, much work has been done on extraction of chemicals responsible for the antimicrobial effect from these plant species. It has been reported that the essential oils extracted from these plants have potent activity against microorganisms [1]. However, the studies have shown that these essential oils have very high MIC (minimal inhibitory concentration) against beneficial enteric bacteria known as probiotics [23].

Probiotic is the term as per WHO definition denotes “live microbial feed supplement which beneficially affects the host animal by improving its intestinal microbial balance.” As the definition clearly indicates, most of the intestinal bacteria have an important role to play in the digestive system. Earlier, probiotics were given to animals to improve their health, but later much research has been put in the development of the probiotics for human health. The major probiotics that are taken in the diets belongs to the genera ofLactobacilli and Bifidobacteria [4]. Apart from that, the gut flora predominately has obligate anaerobes that include Bifidobacteria, Clostridia, Eubacteria, Fusobacteria, Peptococci, Peptostreptococci, andBacteroides. Only about 1% of these bacteria are facultative anaerobes belonging to the genera ofLactobacilli, Escherichia coli, Klebsiella, Streptococcus, Staphylococcus, and Bacilli. In the case of newborns, food habits play a major role in the development of enteric flora. The breastfed babies normally have abundance of Bifidobacteria, while the others have complex microflora in their enteric system.Bifidobacterium sp. can be isolated mostly from the feces of infant milk feed baby. However, in the case of infants fed on normal formula based food products the gut flora is found to be rich in Enterobacteria, Lactobacilli, Bacteroides, Clostridia, and Streptococci. These gut flora help to digest the milk-based food and offer the primary line of defense against the pathogenic bacteria. The infants have weak but developing immune system [5]. These enteric bacteria help the infantile immune system to fight against pathogenic enteric bacteria by lowering the pH of the gut, rendering it unsuitable for pathogenic bacteria to survive [6]. Even the medical practitioners recommend probiotics-based supplement to both patients suffering from enteric diseases. The most popular probiotics supplements belong to the genera of Lactobacilli andBifidobacteria. The recommended dosage of 109–1010 CFU is considered a minimum for healthy enteric system [7].

Present review emphasizes on the synergistic antimicrobial effect of essential oil of the Lamiaceae family and probiotics administered together as flavored fermented milk products. The advantage of using such a combination is its beneficial effect with its antimicrobial property. The probiotics can help in improving the gut epithelial conditions while essential oil acts on killing the pathogens present in the human body.

Health Benefits of Probiotics

Probiotics, though recently popular, have been an integral part of the human diet for centuries. All the civilizations from ancient times have documented the benefits of curd in the human diet. The lactose-tolerant people are always advised to take curd with their diet. The curd is rich in Lactobacillus sp. andStreptococcus sp. These microorganisms utilize the lactose present in milk-based food and convert it to lactic acid [8]. The occurrence of flatulence in carbohydrate-intolerant individuals is also observed with fatty acid. The carbohydrates that are not fully digested due to lack of certain enzymes in human being can also be digested with probiotics. These carbohydrates are fermented into short-chain acids such as butyric acid, lactic acid, or acetic acid [9]. These acids are readily utilized in by human cells for ATP metabolism providing energy to the individuals. The lactic acid also helps in protein metabolism by coagulating the protein chunks from meat inside the intestine [10]. Formation of hydrogen peroxide is also prevented by catalases produced from probiotics preventing protein-caused rancidity [1113]. Hydrolysis of sarcoplasmic protein was also observed with many species of Lactobacillus genus [1416]. Coprecipitation of cholesterol with bile salts at lactic acid-induced lower pH is also observed in in vitro conditions [17].

Probiotic microorganisms are also found to be involved in synthesis of vitamins. The probiotics microorganisms are known to synthesize biotin and vitamin K [18]. Apart from that, they are also involved in the ions absorption such as Mg2+, Ca2+, and Fe3+.

The probiotic microorganisms are also involved in the enhancement of expression of certain pattern recognition receptors. Pattern recognition receptors such as TLRs have active role in wound healing process. The intestinal cells have high need for these receptors for supporting their process of proliferation and differentiation, healing the wounds made due to irregular bowel movement [19]. The short-chain fatty acid produced from carbohydrate metabolism also enhances the process of proliferation and differentiation of gut epithelial cells.

The probiotics have also a major role to play in prevention of allergies in children [5]. However, the connection of probiotics and immune system regulation is still under investigation. It has been observed that with allergy-prone adults and children, the count of Lactobacilli and Bifidobacteria is lower. It has been also observed that administration of probiotic strains during prenatal stage can decrease the chance of atopic eczema. In addition, the production of pattern recognition receptors, interleukin, and growth factors from the probiotic microorganisms in gut epithelia also play an important role in prevention of allergies. Therefore, it can be inferred that these microorganisms have direct role in immune system regulation [5]. Apart from that, these microorganisms also play a role in immune response modulation. The probiotic microorganisms interact with the gut-associated lymphoid tissue (GALT) [20]. The probiotics are involved in cytokine synthesis, that plays an important role in immune system regulation. However, due to insufficient clinical trial, administration of probiotics in immunosuppressed individuals is still prohibited.

It has been also observed from both in vitro and in vivo studies that probiotics may prevent cancer [21]. It has been found that daily intake of fermented milk products substantially decrease the concentration of nitroreductases, azoreductases, and β-glucuronidase in the gut. These microbial enzymes are associated with carcinogen production in the gut [22]. Lactobacillus casei have also shown an antigenotoxic effect. It prevents inducible DNA damage in the tumor target tissues of gastrointestinal tract of rats.

Antimicrobial Effect and Mechanism of Action

Probiotics have a known antimicrobial effect. They are very potent against pathogens. There are several proposed mechanisms for the antimicrobial action of the probiotics. Bacteriocins, organic acids, hydrogen peroxide, diacetyl, and other inhibitory chemicals are released by the probiotics [23]. All of these chemicals are known for their potent antimicrobial effects. Bacteriocins are toxic chemicals released by the probiotics, that are highly potent against most of the bacteria. However, the most feasible mode of action seems to be lowering of pH with release of organic acids such as lactic acid [2425]. In the limiting condition of available substrates inside the intestine, lowering the pH ensures the survival of acidophilic micro-organisms only. The growth of the pathogens gets inhibited at acidic conditions, slowing the metabolic process in them. Lactobacillus strain GG has been reported to produce inhibitory chemicals, possibly a microcin, that have high activity against pathogenic microorganisms. It has been found effective against Clostridium spp., Bacteriodes spp., Enterobacteriaceae spp., Staphylococcus spp., and Pseudomonas spp. in microbiological assays. Lactocidin released by strains of lactobacillus acidophilus is found active against Staphylococcus aureus and Pseudomonas aeruginosa [26]. There has been a study thatLactobacillus acidophilus LB release chemicals that are effective against both gram positive and gram negative microorganisms. These chemicals released in the broth were effective against Staphylococcus aureus, Listeria spp., Salmonella typhimurium, Shigella flexneri, E. coli, Klebsiella pneumoniae, Bacillus cereus, Pseudomonas aeruginosa, and Enterobacter spp. [27]. However, the chemical did not have any inhibitory effect on probiotics strains such as Lactobacillus and Bifidobacterium spp. This can be explained by the similarity of survival conditions of both these microorganisms. Some of the strains ofBifidobacterium spp. have potent activity against Salmonella typhimurium. However, not all the strains ofBifidobacterium spp. have the activity against S. typhimurium. All of the probiotics have higher survivability in low pH conditions. These microorganisms produce acids by breaking the carbohydrate present in the diet. The properties of acid production and acid survivability increase their survivability in the toughest of conditions [2829]. The adherence property of the probiotic microorganisms also ensures their longevity in the human guts [30]. However, the probiotic strains have shown an effective potential in inhibiting the adhesion of pathogen such as E. coli and Salmonella enterica in in vitro conditions [31]. The potential of adhesion inhibition by the probiotics is credited to the mucin production and competitive binding to gut epithelial receptor sites. Lactobacillus acidophilus LA1 has high calcium independent adhesive property that inhibits the invasion of enteropathogenic bacteria. Mucins are complex glycoprotein that inhibits the enterobacterial adhesion by protection of intestinal epithelial cell receptors. Both MUC2 and MUC3 produced by Lactobacillus spp. are potent examples of Mucins that have adhesion inhibitory activity against enteropathogens.

Antimicrobial Effects of Essential Oils from Medicinal Plants

There has been lot of studies in recent year that have established the antimicrobial effect of essential oils of medicinal plants such as plants of the Lamiaceae family [23]. The essential oils predominately present in the leaves of the plant species have a pleasant aroma. They are commonly used in flavor enhancement in food industries, as they are safe for human consumption. These essential oils have been shown to have a bactericidal effect. The plant species of Lamiaceae family have been proven effective against Uropathogen [32]. Table 1 shows the MICs of Coleus aromaticus and Ocimum sanctum (Rama Tulasi andShayama Tulasi) against few known enteric pathogens [32]. The essential oil from the plants of Carum carvi, Coleus aromaticus, Rama Tulasi, Shyama Tulasi, Citrus aurantium var. amara, foeniculumvulgare dulce, Illicium verum, Lavandula angustifolia, Mentha arvensis, Mentha x piperita, and Trachyspermum copticum have been shown to be effective against variety of microorganisms. These plants extracts have been found effective against Bacteroides fragilis, Candida albicans, Clostridium difficile, Clostridium perfringens, Enterococcus faecalis, Escherichia coli, Eubacterium limos, Staphylococcus aureus, Klebsiella oxytoca, Proteus vulgaris, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus mirabilis, and Peptostreptococcus anaerobius [2]. The MICs against these microorganisms varies from 0.1 to 3%v/v. The MICs of the same plant extracts against probiotic microorganisms such as Bifidobacterium bifidum, Bifidobacterium longum, Lactobacillus acidophilus, and Lactobacillus plantarum are much higher in magnitude than the pathogens [2]. Therefore, if the dosage of essential oil is low, then it effectively wipes out the pathogens without harming the beneficial probiotics.

Proposal on Synergistic Effect of Probiotics and Essential Oil from Plants

The essential oils have high MIC values for probiotics, while it is effective in much lesser concentration against the pathogens. The above phenomenon makes it possible that both probiotics and essential oil can be administered together to cure pathogenic infection in human gut. They both can be combined to form essential oil-flavored fermented milk products such as flavored curd beverages or flavored yogurt. Antibiotics coupled with probiotics are already present in the market, but these medicines mostly face stiff challenge from antibiotic-resistant bacteria. Further frequent use of the antibiotics may lead to the development of antibiotic resistance in the pathogenic microorganisms too. Hence, the strategic use of probiotics may be beneficial to curb the growing phenomenon of antibiotic resistance. Probiotics have antimicrobial properties associated with the production of bacteriocin-like chemicals. However, it mostly arrests the proliferation of the pathogens by lowering the pH in the gut environment. The pathogens do not normally have any mechanism against the action of essential oils. Essential oils are resistant against enzymatic activity of β-lactamase produced as a countermeasure against β-lactam antibiotics. The use of probiotics lowers the survivability chances of pathogen, while the essential oil in lower dosage ensures their complete killing inside the human digestive tract. The probiotics may also impart its good benefits discussed earlier. Apart from that, the fermented milk product will surely impart benefits in terms of supplying nutrients such as sugar, water, salt, and acid to the human body. Adding essential oil will not only give an aromatic flavor to these fermented milk beverages or products, but also increase their shelf like considerably by preventing the microbial spoilage. The product will act as both probiotic health product and preventive antimicrobial product against enteric pathogens.

In an independent study, beverages A, B, and C were prepared with probiotic curd (109 CFU/ml) [33] with varying concentration of essential oil of Coleus aromaticus, Rama Tulasi and Shyama Tulasi, respectively [1]. The beverages A1, A2, and A3 were prepared with essential oil of Coleus aromaticus; beverage B1, B2, and B3 with essential oil of Shyama Tulasi and beverages C1, C2, and C3 with essential of Rama Tulasi in varying concentrations of 1, 2, and 3 μl/ml respectively. These beverages were then grown with common enteric pathogens in equal concentration, measured by count of CFU, in nutrient broth for 24 hours in airtight culture vials at 37°C to simulate the anaerobic condition prevailing in the intestine [34]. The individual vial was tested for the traces of pathogen as seen in Table 2 with − sign indicating the cidal effect of the beverage against the pathogen (no growth of the pathogens), while + sign indicated the growth of the pathogen. The sample beverages were found to be highly effective in inhibiting the growth of the pathogen. The shelf life of the beverages was also found to be significantly higher than normal probiotics [34]. The test results can be interpreted as the beverage’s capacity for prevention against enteric pathogens. The use of beverage does not need the stringent FDA regulations, yet it will impart the benefit of preventive diseases.


Probiotics and essential oils both have a great potential in terms of their beneficial effect against microbial gut infection. They also show a synergistic effect that is normally higher than any known drug due to their complementary actions. Since most of these medicinal plants are edible, their extracts as food product do not have any side effects with low dosage. Therefore, these products may be very beneficial for human beings. However, much research is needed to be put into these studies, as drug regulatory authorities still have strong regulations against usage of plant extracts as medicines.


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Essential Oils & The Blood Brain Barrier

By Dr. David Stewart, Ph.D.,R.A.

It was thought for years that the interstitial tissues of the brain served as a barrier to keep damaging substances from reaching the neurons of the brain and the cerebrospinal fluid. Instead of a barrier, it would be more accurate to consider it as a sieve or filter through which only molecules of a certain size or smaller can pass.

Most of the molecules of the substances used in chemotherapy are too large to pass through the blood-brain filter, which is why doctors say that chemotherapy doesn't work on brain cancer. Some of the smaller molecules get through, but not the whole suite of drugs intended.

Doctors don't know for sure, but it seems that in order to cross the blood-brain barrier, only molecules less than 800-1000 atomic mass units (amu) in molecular weight can get through. Lipid solubility seems to be another factor which facilitates passing through the blood-brain barrier. Water soluble molecules don't usually penetrate into brain tissue, even when very small. The molecules of essential oils are all not only small, but lipid soluble as well.

In fact, when it comes to essential oils, small molecules (less than 500 amu) are what they are made of. That is why they are aromatic. The only way for something to be aromatic is for the molecules to be so small that they readily leap into the air so they can enter our noses and be detected as odor and smell.

That is why oils for cooking or massage, such as corn, peanut, sesame seed, safflower, walnut, almond, canola, olive and other oils pressed from seeds are not aromatic. Sure, they have a smell, but you can't smell them across the room in minutes as one can when you opens a bottle of peppermint, hyssop, or cinnamon oil. Essential oils of every species cross the blood-brain barrier.

This makes them uniquely able to address disease, not only from a physical level, but from a more basic and fundamental level-that of the emotions which are often the root cause of physical illness.


Because of the tiny molecular structure of the components of an essential oil, they are extremely concentrated. One drop contains approximately 40 million-trillion molecules. Numerically that is a 4 with 19 zeros after it: 40,000,000,000,000,000,000. We have 100 trillion cells in our bodies, and that's a lot. But one drop of essential oil contains enough molecules to cover every cell in our bodies with 40,000 molecules. Considering that it only takes one molecule of the right kind to open a receptor site and communicate with the DNA to alter cellular function, you can see why even inhaling a small amount of oil vapor can have profound effects on the body, brain, and emotions. Sometimes too many oil molecules overload the receptor sites, and they freeze up without responding at all, when a smaller amount would have been just right. This is why we say that when using oils, "sometimes less is better." Sometimes more is better, too. Knowing the difference is the art of aromatherapy.

Essential oils are mixtures of dozens, even hundreds, of constituents, all of which are composed of carbon and hydrogen and sometimes oxygen. All essential oils are principally composed of a class of organic compounds built of "isoprene units."

An isoprene unit is a set of five connected carbon atoms with eight hydrogens attached. Their molecular weight is only 68 amu, which is very small, indeed. Molecules built of isoprene units are all classified as "terpenes." Terpenes are what make essential oils unique in the world of natural substances.


Phenylpropanoids are compounds of carbon-ring molecules incorporating one isoprene unit. They are also called hemiterpenes. There are dozens of varieties of phenylpropanoids.

They are found in Clove (90%), Cassia (80%), Basil (75%), Cinnamon (73%), Oregano (60%), Anise (50%), Peppermint (25%). While they can create conditions where unfriendly viruses and bacteria cannot live, the most important function performed byphenylpropanoids is that they clean the receptor sites on the cells. Without clean receptor sites, cells cannot communicate, and the body malfunctions, resulting in sickness.


Monoterpenes are compounds of two isoprene units, which is ten carbon atoms and sixteen hydrogen atoms per molecule- molecular weight 136 amu. There are an estimated 2,000 varieties of monoterpenes.

Monoterpenes are found in most essential oils: Galbanum (80%), Angelica (73%), Hyssop ((70%), Rose of Sharon (54%), Peppermint (45%), Juniper (42%), Frankincense (40%), Spruce (38%), Pine (30%), Cypress (28%), and Myrtle (25%).

While offering a variety of healing properties, the most important ability of the monoterpenes is that they canreprogram miswritten information in the cellular memory. With improper coding in the DNA, cells malfunction and diseases result, including lethal ones such as cancer.


Sesquiterpenes are compounds of three isoprene units, which is fifteen carbons and twenty-four hydrogens per molecule- molecular weight 204 amu. There are more than 10,000 kinds of sesquiterpenes. Sesquiterpenes are the principal constituents of Cedarwood (98%), Vetiver (97%), Spikenard (93%), Sandalwood (Aloes) 90%, Black Pepper (74%), Patchouli (71%), Myrrh (62%), and Ginger (59%). They are also found in Galbanum, Onycha, and Frankincense (8%).

Sesquiterpene molecules deliver oxygen molecules to cells, like hemoglobin does in the blood. Sesquiterpenes can also erase or deprogram miswritten codes in the DNA. Sesquiterpenes are thought to be especially effective in fighting cancer because the root problem with a cancer cell is that it contains misinformation, and sesquiterpenes can erase that garbled information. At the same time the oxygen carried by sesquiterpene molecules creates an environment where cancer cells can't reproduce. Hence, sesquiterpenes deliver cancer cells a double punch-onethat disables their coded misbehavior and a second that stops their growth.

The American Medical Association (AMA) has said that if they could find an agent that would pass the blood-brain barrier, they would be able to find cures for ailments such as Lou Gehrig's disease, multiple sclerosis, Alzheimer's disease, and Parkinson's disease. Such agents already exist and have been available since Biblical times. The agents, of course, are essential oils-particularly those containing the brain oxygenating molecules of sesquiterpenes.


The big triple punch combination of "PMS" (Phenylpropanoids, Monoterpenes, and Sesquiterpenes) found in essential oils is very powerful in addressing many illnesses, injuries, and disease conditions. That is because this combination offers the following:

First, you clean the receptor sites allowing the proper transfer of hormones, peptides, neurotransmitters, steroids, and other intracellular messengers. (The Phenylpropanoids do that.)

Second, you deprogram or erase the wrong information from cellular memory stored in the DNA. (The Sesquiterpenes take care of that.)

Third, you reprogram the cells with the correct information so they can function properly. (The Monoterpenes do this.)

These three classes of chemical components are why essential oils can sometimes affect a healing that is nearly instant and also permanent. What they simply do is to restore the body back to its natural state of balance and health. While a specific oil may have one or two of these three classes of compounds as its predominant chemistry, all the Biblical oils contain some of all of them. This is one secret to their amazing healing abilities.

So there you have it in a nutshell: The way the blood-brain barrier works and the biochemistry of one of the ways essential oils can help achieve a healing.

More Than Just A Spice, Oregano Essential Oil And Its Therapeutic Benefits

More than Just a Spice, Oregano Essential Oil and its Therapeutic Benefits

An ever growing body of research is positive and suggestive of additional study and inquisition into the powerful healing attributes of essential oils. There is growing interest for personal use to improve health and modern medical science is validating therapeutic benefit.

The medicinal use of essential oils is well documented has been readily considered to be one of the most potent forms of natural medicine. The need for more cost effective and intuitive approaches to healthcare along with public demand has increased the popularity of essential oils exponentially. They are readily available as key components in a variety of health and beauty products and as individual commodities.

For those who utilize essential oils personally along with a growing number of Health Care providers who are incorporating more holistic therapies, there has been greater acceptance and openness regarding the benefit and simplicity with which they can be incorporated into models of health. Various maladies and a host of ailments along with an almost endless list of practical uses are all within the scope of the medicinal value of pure essential oils. Oregano essential oil is certainly no exception.

Within the plant family of Lamiaceae is the genus Origanum consisting of more than 44 specific species and at least 6 different subspecies. In addition there are 18 or more naturally occurring hybrids and 3 botanical varieties. Included within this host of plants are several types of the unmistakably herbaceous and potent oregano. Revered for its traditional role as a cooking herb many are now discovering the vast health benefits associated with the essential oil of oregano.

Although many differing species and subspecies exist, most oregano available is considered non-therapeutic and best suited for cooking. Generally only two species are revered for their medicinal potential.  Thymus capitatus, (Spanish oregano) primarily found in Spain and Origanum vulgare which is predominant throughout the rest of the Mediterranean.  In a process known as chemical polymorphism these two distinct oregano plants develop specific and potent chemistry.

Wild crafted Origanium vulgare L. within the subspecies of hirtum seems to be especially potent. Carvacrol is a phenolic monoterpene present in many essential oils of the family Lamiaceae.  As a primary compound comprising 60% or more of the chemical profile of the subspecies hirtum, oregano has proven to be invaluable for many differing health circumstances. Typically most users of oregano for health practices give great value to its strong antimicrobial benefit. Indeed origanum vulgare due primarily to its phenolic compounds of carvicrol and thymol, it is far superior to many other essential oils in this regard. As is the circumstance with many essential oils its antimicrobial benefit is not limited to one strain of bacterium. Individual immunity with strong resilience is essential to health and all four microbe categories, bacterium, viral, fungal and protozoic can be heavily diminished or eradicated through the use of oregano essential oil. Research has shown it to be effective against candida albicans, the aspergillus mold, staphylococcus, campylobacter, klebsiella, e.coli, giardia, pseudomonas, salmonella, and listeria just to name a few.

When assayed against several types of human pathogenic bacteria, O. vulgare demonstrated the highest antimicrobial activity among all those tested. It has long been my experience that oregano essential oil, when used properly, elicits appropriate and clinically relevant outcomes in direct patient care.

Willing to overlook the strong and familiar aromatic overtones, peer reviewed research and personal experience has many devoted aroma therapists and health professionals recommending oregano essential oil for a variety of health additional concerns.

The role of antioxidants in the body is a well understood nutritional principle. Fatty acids are necessary for proper brain development and function. In the brain they are susceptible to oxidative damage (free radicals) leading to impaired function.  Phenolic compounds like those found in Oregano essential oil demonstrate active protection against the damaging effects of oxidation.

Chronic inflammation plays a major role in the development and perpetuation of many illnesses and disease states.  The relevant concept with inflammation is its relentless destruction of tissue when developed into chronic stages. In clinical practices it is well understood that chronic inflammation and pain are intrinsically connected. The pro-oxidative states which exist as an inflammatory partner can be significantly reduced through the use of oregano essential oil.

In many studies carvacrol produced significant inhibitory effect on nociception suggesting that this potent monoterpene is an effective tool in the management of chronic pain. I have found that topical use with dilution is reliable in reducing inflamed joints and managing arthritic conditions. The advantages of repeated application models when needed should not be overlooked. The ease and simplicity of use associated with essential oils makes them an effective self-management opportunity for many patients.

A surprisingly large number of physician and hospital visits are a direct result of gastric issues. Ulcers and gastric lesions comprise many such patient, physician interactions. It has now been shown through research that carvacrol has many pharmacological targets when used to treat gastric ulcers and lesions.  Helicobacter pylori, a known cause of a significant number of gastric ulcers, is greatly reduced in the presence of oregano essential oil.  Small amounts of oregano periodically ingested in a capsule seems to be most clinically relevant and offers the most targeted approach in patient care for these types of conditions.

One of the most exciting areas of emerging research with essential oils is their ability to differentiate between healthy viable cells and unhealthy ones. Cell death is a normal part of the cell cycle. All cells have an expected and useful life span. In the case of damaged cells the timely stimulation of apoptosis (cell death) is critical. Carvacrol may induce apoptosis through direct activation of the mitochondrial pathway. Stimulation of apoptosis in damaged cells is an attribute that many essential oils seem to possess. Clove, Thyme, Frankincense, citrus and many additional essential oils have shown varying degrees of benefit.

It is clear that oregano is more than just a spice for cooking. As an essential oil it is a potent, multifaceted medicinal agent. Through its proper use it provides many direct health benefits. As a physician I have come to understand and have incorporated many of their therapeutic and clinical benefits into direct patient care. It is my belief that essential oils will continue to emerge as an exciting and appropriate approach to health.


  1. Soković, M., et al., Antibacterial effects of the essential oils of commonly consumed medicinal herbs using an in vitro model.Molecules. 2010. Oct 27;15(11):7532-46.
  2. Lang, WZ. and Lu, CH., Carvacrol-induced [Ca2+]I rise and apoptosis in human glioblastoma cells. Life Sci. 2012 May 15;90(17-18):703-11.
  3. Silva, FV., et al., Anti-inflammatory and anti-ulcer activities of carvacrol, a monoterpene present in the essential oil of oregano. J Med Food. 2012 Nov;15(11):984-91.
  4. Cavalcante Melo FH., et al., Antinociceptive activity of carvacrol (5-isopropyl-2-methylphenol) in mice. J Pharm Pharmacol. 2012 Dec;64(12):1722-9.
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Why are Essential Oils Not Yet Fully Accepted?

By Dr. E. Joan Barice, MD, MPH

There are a small but growing number of physicians and other health professionals who accept and use essential oils. It is particularly difficult for me, having benefited so much from the use of therapeutic essential oils, to accept the resistance of conventional medicine to them. But as a physician I can understand some of the reasons. Here are some of my thoughts, just one person’s thoughts.

The therapeutic use of essential oils is just being rediscovered. It was practiced by ancient cultures such as in China, Egypt and India. There is much documentation in the Scripture and in ancient medical texts of their use. It was only been since the 1940’s that the medical benefits of oils were rediscovered and modern research began. There is research confirming the scientific rationale for many ancient uses.

Our modern science does not accept ancient folk use or ancient science, which does not use the same terminology or methods as ours. Our modern science has made much progress and many amazing discoveries that have helped save lives. The ancient Egyptians and other cultures left us evidence of their intelligent science thousands of years old, but it was different from our modern science which is just hundreds of years old.

There is a wealth of modern clinical research demonstrating positive results and safety of the oils for many conditions but many studies lack adequate control groups for comparison. Done by well-intentioned people with expertise in oils but not necessarily in modern clinical research, these studies are mostly not acceptable to modern medicine because of the methods used or small numbers of patients. Clearly essential oils have helped patients with MRSA and relentless pain and many other conditions, from first-aid to intensive care to end-of life-care, and have done no harm. They are being used in many hospitals around the world including many in the United States.

An analogy regarding research evidence would be acupuncture, practiced for thousands of years as folk medicine in China. An NIH consensus panel reviewed the vast amount of research and concluded that though studies have shortcomings, there is enough evidence of effectiveness and safety in so many patients to recommend it for treatment of back pain and nausea and other conditions.

Before doctors will accept essential oils for use in patients, most will need large, randomized studies showing effectiveness and safety. There is not much interest on behalf of conventional medicine or drug companies in doing research on essential oils because there isn’t as much money to made with them.

In general the medical establishment tends to resist anything new that is not already clearly proven by western research standards. This is nothing new. For example, it took 250 years and many deaths before the medical establishment of that time accepted Vitamin C containing foods as a cure for scurvy.

Funding for research on complementary medicine is limited compared to that available for drug studies. It might be that the oils, which are considerably less costly than drugs are not likely to be as profitable.

Another reason may be the approach to disease is different for oils vs. most drugs. Oils help the body heal itself, by releasing substances that promote healing while drugs often substitute for those natural substances and shut down their production by the body, but sometimes they are so powerful that they overwhelm the body’s own healing process, and sometimes, too often, drugs do harm.

The most important thing to consider always is what is best for the patient. As a patient, I have experienced tremendous health benefits using essential oils, and I believe they have much to offer. Which is why I am committed, as a physician and researcher, to doing randomized studies to get the objective answers. In the meantime, I believe these God-given natural remedies have the potential to help a wide variety of conditions from MRSA to burns to chronic pain and much more without doing harm. They have a long track-record of effectiveness, safety and they are inexpensive. When we do not have all the answers how to best help our patients, when a patient may suffer or die because we do not have an effective treatment for him or her, when there is a lot of evidence that oils might do good, and do no harm, then I believe it is justified to use them in medicine. And not to wait until it is too late for that patient.

Dr. E. Joan Barice, MD, MPH, is Board Certified in Internal Medicine, Preventive Medicine, and ASAM Certified in Addiction Medicine and has special expertise essential oils, and acupuncture She graduated from the University of Florida, Stanford Medical School and Harvard School of Public Health, and has an Honorary Doctorate in Humanities from Northwood University. She is the author of the Palm Beach Long-Life Diet published by Simon & Schuster. Dr. Barice is on the faculties of University of Miami Miller School of Medicine, Nova Southeastern University and Florida Atlantic University, and has received numerous awards for her contributions to medicine and public health. Dr. Barice has studied and used therapeutic-grade essential oils for over ten years.

Staying Healthy With Essential Oils

The effectiveness of essential oils cannot be fully understood without some discussion of frequency. Frequency is the measurable rate of electrical energy flow that is a constant between any two points. Everything has a frequency. Dr. Robert O. Becker in his book The Body Electric establishes that the human body has an electrical frequency and that much about a person’s health can be determined by its frequency. In 1992, Bruce Taino of Taino Technology, an independent division of Eastern State University in Cheny, Washington, built the first frequency monitor in the world. Taino has determined a healthy body frequency is 62-72 Hz. When the frequency drops, the immune system is compromised.

Body frequency and Diseases

  • If the frequency drops to 58 Hz, cold and flu symptoms appear.
  • If the frequency drops to 55 Hz, diseases like Candida take hold.
  • If the frequency drops to 52 Hz, Epstein Bar becomes present.
  • If the frequency drops to 42 Hz, the body is at risk for Cancer.

According to Dr. Royal R. Rife, every disease has a frequency. He found that certain frequencies can prevent development of disease and that others would destroy disease. Substances with higher frequency will destroy diseases of a lower frequency. The study of frequencies raises important questions concerning the frequencies of substances we eat, breath and absorb. Many pollutants lower healthy frequencies.

Frequency and Foods

  • Processed canned foods have 0 frequency
  • Fresh produce has up to 15 Hz
  • Dry herbs from 12 to 22 Hz.
  • Fresh herbs from 20 to 27 Hz.
  • Essential Oils start at 52 and go as high as 320 Hz.

Clinical research shows that essential oils have the highest frequency of any natural substance known to man. Frequency and Essential Oils:

  • Essential Oils create and environment in which disease, bacteria, virus, fungus etc., cannot live.
  • Research shows 100% pure essential oils are immune stimulating.
  • More research shows that many of the “super bugs” that has modern medicine so concerned, cannot survive in the presence of essential oils.
  • There has not been a pathogen known to resist Essential oils by mutating.
The battle against multi-resistant strains: Renaissance of antimicrobial essential oils as a promising force to fight hospital-acquired infections

Warnke PH, Becker ST, Podschun R, Sivananthan S, Springer IN, Russo PA, Wiltfang J, Fickenscher H, Sherry E
Journal of Cranio-Maxillo-Facial Surgery, 2009


Hospital-acquired infections and antibiotic-resistant bacteria continue to be major health concerns worldwide. Particularly problematic is methicillin-resistant Staphylococcus aureus (MRSA) and its ability to cause severe soft tissue, bone or implant infections. First used by the Australian Aborigines, Tea tree oil and Eucalyptus oil (and several other essential oils) have each demonstrated promising efficacy against several bacteria and have been used clinically against multi-resistant strains. Several common and hospital-acquired bacterial and yeast isolates (6 Staphylococcus strains including MRSA, 4 Streptococcus strains and 3 Candida strains including Candida krusei) were tested for their susceptibility for Eucalyptus, Tea tree, Thyme white, Lavender, Lemon, Lemongrass, Cinnamon, Grapefruit, Clove Bud, Sandalwood, Peppermint, Kunzea and Sage oil with the agar diffusion test. Olive oil, Paraffin oil, Ethanol (70%), Povidone iodine, Chlorhexidine and hydrogen peroxide (H(2)O(2)) served as controls. Large prevailing effective zones of inhibition were observed for Thyme white, Lemon, Lemongrass and Cinnamon oil. The other oils also showed considerable efficacy. Remarkably, almost all tested oils demonstrated efficacy against hospital-acquired isolates and reference strains, whereas Olive and Paraffin oil from the control group produced no inhibition. As provenin vitro, essential oils represent a cheap and effective antiseptic topical treatment option even for antibiotic-resistant strains as MRSA and antimycotic-resistant Candida species.


Warnke PH, Becker ST, Podschun R, et al. The battle against multi-resistant strains: Renaissance of antimicrobial essential oils as a promising force to fight hospital-acquired infections. J Craniomaxillofac Surg. 2009;37(7):392-397.