NATURAL AND EFFECTIVE ANTIFUNGALS
Fungi are ubiquitous. They are all around us and inside us. They are on or in just about every natural substance we experience. About 100,000 species of fungi have been formally described by taxonomists, but the global diversity of the fungus kingdom is not fully understood. Based on the ratio of the number of fungal species to the number of plant species in selected environments, the fungal kingdom has been estimated to contain about 1.5 million species. Many of these species are used to create beneficial products for the human body, such as medications like antibiotics, statins and antifungals. Without fungi we would not have leavened breads or beer or wine.. Additionally, some mushroom varieties are believed to be highly therapeutic.
However, there are some fungus species which are known to create disease in humans, varying from mild forms, such as ringworm and dandruff, to more serious lung infections that can be fatal. Some believe that imbalances and out-of-control growth of fungi within the body may be responsible for many serious conditions such as cancer, heart disease, depression and autoimmune diseases.
Three classes of fungi commonly afflict humans: the Aspergillus species found on grains and nuts (which produce aflatoxins that can cause liver failure and cancer), the Candida species, which create yeast infections externally and internally, and dermatophytic fungi, which cause local, surface infections like ringworm and athlete’s foot.
Other varieties, such as Cryptoccocus species, Histoplasma species and Pneumocystis species are opportunistic fungi, in that they do not normally affect humans with healthy immune systems, but can activate and cause life-threatening infections in those with compromised immune systems, such as those with AIDS or undergoing chemotherapy.
Given the surprising ability of essential oils to control or kill a wide spectrum of bacteria and viruses, it is no surprise that researchers would investigate the ability of essential oils to control harmful (pathogenic) fungi, particularly those responsible for human ailments. A key reason for investigating the antifungal abilities of natural essential oils is that allopathic antifungal remedies are extremely toxic substances with a myriad of dangerous side effects including renal failure, liver toxicity, hormone imbalance and serious allergic reactions. Researchers reasoned that if they could show that essential oils had real antifungal properties they could use them to reduce dosages of allopathic drugs, thereby reducing the probability of serious side effects.
General Studies
One of the earliest, broad-range studies was done in Germany at the University of Leipzig in 1996. In this study, tea tree oil was tested on over 100 different fungi strains, including dermatophytes, Candida species and Malassezia strains (yeasts). Researchers found significant antifungal activity even at very high dilution levels. Researchers concluded that the antifungal activity of tea tree oil made it practical for the “therapy of fungal infections of the skin and mucous membranes as well as in the treatment of dandruff.
A thorough research survey done in Poland in 2003 estimated that there had been at least 500 studies done on the antimicrobial properties of essential oils as of that date, many of them focusing on fungi.
A recent study done in Serbia, at the Institute for Biological Research, tested thyme, spearmint and peppermint oils against 17 different pathogenic fungi. Additionally, they compared the antifungal power of the essential oils with bifonazole, a commercial fungicide. The results showed that “bifonazole had much lower antifungal activity than the oils” and that “essential oils of thyme, spearmint and peppermint possess great antifungal potential and can be used as natural preservatives and fungicides.”
Food scientists and environmental engineers have also studied essential oils for their antifungal properties. In fact, today, it is common for food producers to use rosemary oil, orange oil, peppermint oil and even lavender oil to help extend food product shelf life, because all of these oils have been shown to greatly reduce the onset of mold. One such study concluded that essential oils ‘may be recommended as safe plant-based antimicrobials as well as antioxidants for enhancement of shelf life of food commodities by checking their fungal infestation, aflatoxin production as well as lipid peroxidation.”
In homes and buildings, pine oil, cinnamon oil and thyme oil are unusually effective in clearing air and sanitizing buildings infected with mold, including helping to eliminate ‘sick building syndrome,’ and ‘toxic mold syndrome.’ In many cases, thyme, clove and cinnamon oils were found to be much more effective in eliminating mold spores than bleach or commercial anti-mold chemicals.
Candida species, including Candida albicans
Candida infections are of particular concern because they are common both internally and externally in the human body. Candida is a family of yeasts which are responsible for a variety of conditions, including thrush (oral candidiasis), diaper rash, vaginal yeast infections and nail bed infections. Candida fungus can also grow in the lungs liver, spleen, blood, brain, eye, kidney and heart. When immune systems are compromised, candida infection can become systemic and spread throughout the body creating life-threatening conditions. Candida organisms may build up in the intestines because of frequent use of antibiotics, which kill the bacteria that normally keep candida under control.
A study in Brazil in 2008 at the Federal University of Rio Grande do Sul tested lemongrass oil on five different Candida varieties and concluded that “lemongrass . . . has a potent in vitro activity against Candida species.” Another study in Japan at the Teikyo University Institute of Medical Mycology tested 12 different essential oils on Candida albicans and found that four of them, lemongrass, thyme, patchouli and cedarwood inhibited mycelia (tiny filaments that are the growth structure of a fungus) growth even when greatly diluted. Stronger solutions inhibited all growth of Candida albicans. Researchers concluded that their results provided “experimental evidence suggesting the potential value of lemongrass oil for the treatment of oral or vaginal candidiasis.”
A George Washington University Medical Center study investigated the anti-candida effects of oregano oil in 2001. Even in high dilutions, oregano oil “was found to completely inhibit the growth of Candida albicans in culture.” Researchers concluded with the following statement: “The results of our study encourage examination of the efficacy of oregano oil in other forms of systemic and superficial fungal infections and exploration of its broad spectrum effect against other pathogenic manifestations, including malignancy.”
Aspergillus species, including Aspergillus flavus
Aspergillus fungi are found on nuts and grains, including peanuts. They are dangerous to humans because of their ability to product aflatoxins which are extremely toxic to the liver, carcinogenic and potentially life-threatening. Scientists in the food industry are constantly trying to find new and better ways to kill or immobilize these fungi, so they will not be present in our food supply. In recent years, more and more studies have pointed to essential oils as an ideal natural solution. One such study was done in Egypt in 2002. Twelve essential oils were tested against 3 different species of aspergillus fungi and a fusarium species. Thyme, cinnamon, spearmint, basil, anise and caraway were all found to “completely inhibit” the fungi in solutions ranging from 500 to 3000 ppm. The test fungi were to some degree sensitive to all 12 essential oils, but the most antifungal were thyme, cinnamon, anise and spearmint. In other studies, summer savory oil and orange oil have also been identified as safe and effective eco-friendly fungicides in destroying Aspergillus fungi.
Dermatophytes
There are some 40 different species of dermatophytes which can cause infections of the skin, hair and nails. Normally these infections do not go beyond the outer surface of the skin in persons with healthy immune systems. The most common conditions resulting from dermatophytes include:
Athlete’s foot (tinea pedis)
Jock itch (tinea cruris)
Scalp ringworm (tinea captitis)
Facial ringworm (tinea faciei)
Ringworm of the body (tinea corpora)
Ringworm of the hands (tinea manuum)
Ringworm of the nail (onychomycosis)
A 2007 study done at the University of Turin, Italy, tested 7 essential oils against dermatophyte fungi. While all the oils showed some inhibitory activity,”thyme and clove were found to be the oils with the widest spectrum of activity against all fungi tested.” The study further concluded that “some essential oils are very active on dermatophytes and dematiaceous fungi.”
More recent studies examined clove oil and lemongrass oil on dermatophytes. In 2009, at the University of Porto, Portugal, scientists found that clove oil inhibited or killed a variety of fungi, including dermatophytes, by creating lesions in the cell walls of the fungi. The study further found that “clove oil has considerable antifungal activity against clinically relevant fungi,” including those strains that had already developed resistance to fluconazole, an allopathic antifungal. Also in 2009, at the Banaras Hindu University in India, lemongrass oil was tested against a variety of dermatophyte fungi. Their results showed that “the essential oil…displayed strong antifungal effects. . . . The results provide a scientific validation for the use of [lemongrass] in the treatment of dermatophyte infections and may be recommended as an alternative to synthetic drugs for topical application.”
Copyright© March, 2010 VitalScience.org


