Tea tree oil in wound healing: A Review on Herbal essential oil

Bhupendra G. Prajapati

The present review highlights use of tea tree oil obtained from Melaleuca alternifolia belonging which is widely available in Australia and Asia. The products of tea tree oil showed effective against bacterial, viral and fungal organisms. It is also a powerful immunostimulant. It consists of mainly two constituent terpinen-4-ol and cineole.

It has been extensively studied by Australian research and still the projects going on to find out its usefulness to mankind. The review covers information like tea tree oil origin, its chemical constituents, different products as well as futures research going.

Introduction to wound

Wound healing is the process of repair that follows injury to the skin and other soft tissues. Wounds may result from trauma or from a surgical incision. In addition, pressure ulcers (also known as decubitus ulcers or bed sores), a type of skin ulcer, might also be considered wounds. The capacity of a wound to heal depends in part on its depth, as well as on the overall health and nutritional status of the individual. Following injury, an inflammatory response occurs and the cells below the dermis (the deepest skin layer) begin to increase collagen (connective tissue) production. Later, the epithelial tissue (the outer skin layer) is regenerated. Dietary modifications and nutritional and herbal supplements may improve the quality of wound healing by influencing these reparative processes or by limiting the damaging effects of inflammation. The common symptoms are Symptoms include swelling, stiffness, tenderness, discoloration, skin tightness, scabbing, itching, and scar formation.

Herbs in Wound healing

Herbs include flowering plants, shrubs, trees, moss, fern, algae, seaweed or fungus. In most cultures, including Western culture, herbs are used not only as a part of the treatment of disease, but also in the enhancement of life, physically, emotionally and spiritually. Plant parts, including flowers, fruits, leaves, twigs, bark, roots or seeds, are all considered useful.

While many herbs may be useful in wound healing, it is important that wounds be properly cleaned and dressed before any herbal preparations are applied. This will prevent infection. Topical aloevera ¹ , gotukola ^{2, 3, 4} , aescin ⁵ , honey6, chamomile ^{7, 8} , alginic acid and tea tree ⁹ .

Tea tree oil

Tea tree oil is the essential oil from the leaves of the Australian Melaleuca alternifolia tree, a member of the botanical family Myrtaceane . The tea tree grows and available in Australia and Asia; a tall evergreen tree with a white, spongy bark. The oil from the leaves is used medicinally. The Australian Aborigines were the first to unearth the benefits of Tea Tree long ago when they began to harvest the leaves for their medicinal use; crush leaves used to treat cuts and skin infections. Captain James Cook and his crew named the tree “tea tree,” using its leaves as a substitute for tea as well as to flavor beer. Australian soldiers participating in World War I were given tea tree oil as a disinfectant, leading to a high demand for its production. Tea Tree oil products are now increasingly sought after as extensive scientific studies over recent years have shown it to be effective against bacterial, viral and fungal organisms whilst being a powerful immunostimulant, increasing the body's ability to fight off illness or infection.

The tea tree oil consists of extracted obtained by steam distillation from the leaves and twigs of the native Australian shrub Melaleuca Alternifolia. The tea tree oil for therapeutic use is clear/pale yellow in appearance with a clean, fresh medicinal aroma. It is non-toxic and non-irritating to the skin. The oil has been found to be ten times more powerful antiseptic than carbolic acid (Table 2). It can alleviate inflammation and may help wound healing by encouraging tissue regeneration. It is generally non-irritating but as with all essential oils those with sensitive skin should use the oil in low dilutions to begin with. Melaleuca Oil is also a parasiticide and used by many as a flea, head louse and insect repellent.

Tea tree oil is natural antifungal, antibacterial, antiviral, anti-infection oil. It is effective against nail fungus, ringworm, athlete's foot, dandruff, acne and many types of infestations including lice, mites and scabies. Tea tree oil is not just soothing and disinfecting; it is capable of penetrating into the lower skin layers with its anti-inflammatory, disinfectant, analgesic (pain killing) and cicatrizant (wound-healing) qualities. It helps the skin to heal by encouraging the formation of scar tissue. (Table 1)

Active constituents of tea tree oil

The main constituent of tea tree oil is terpenoids. As per the Australian standards, the amount of important compound, terpinen-4-ol must be at least 30% and cineole (15%). The entire constituent along with percentage has shown in Table 3. The tea tree oil has ability to kills fungus and bacteria, including those which are resistant to some antibiotics. ^{10, 11} For common acne, a double-blind trial compared the topical use of 5% tea tree oil to 5% benzoyl peroxide. ¹² Although the tea tree oil was slower and less potent in its action, it had far fewer side effects and was thus considered more effective overall. A double-blind trial found that a 10% tea tree oil cream was as effective as anti-fungal medicine at improving symptoms associated with athlete’s foot, though it was not more effective than a placebo for eliminating the fungal infection. ¹³ A double-blind trial found 100% tea tree oil applied topically was as effective as the anti-fungal medicine clotrimazole (Lotrimin®, Mycelex®) for people with fungus affecting the toe nails, a condition known as onychomycosis. ¹⁴ In another double-blind trial with toenail fungus sufferers, a combination of 5% tea tree oil and 2% butenafine (Mentax®), a synthetic anti-fungal drug, in a cream proved more effective than an unspecified concentration of tea tree oil in cream alone. ¹⁵ The results are not entirely surprising, as the tea tree product alone was probably not at a sufficiently high enough concentration to be effective.

A preliminary trial found that rinsing the mouth with 1 tablespoon (15 ml) tea tree oil solution four times daily effectively treated thrush (oral yeast infections) in AIDSpatients. ¹⁶ Solutions containing no more than 5% should be used orally and should never be swallowed. One small clinical trial found that use of a 4% tea tree oil nasal ointment as well as a 5% tea tree oil body wash was slightly more effective than standard drugs used to prevent the spread of the bacteria. ¹⁷

Tea Tree Oil has been widely used topically for the treatment of bactericidal and fungal infections. It shows antimicrobial activitiy against Proprionibacterium acnes, taphylococcus aureus, E. coli, Candida albicans, Tr. mentagrophytes, and Tr. Rubrum ¹⁸ . In double- blind randomized trials there are conflicting results. In some trials mycologic cure is found to be comparable to clotrimazole, in other trials only symptomatic relief could be postulated ¹⁹ . Tea tree oil at a strength of 70–100% should be applied moderately at least twice per day to the affected areas of skin or nail. ⁹ For topical treatment of acne, the oil is used at a dilution of 5–15%. Concentrations as strong as 40% may be used—with extreme caution and qualified advice—as vaginal douches. For thrush in immune-compromised adults, tea tree oil diluted to 5% or less is used in the amount of 1 tablespoon (15 ml) four times daily (as a mouth rinse). Tea tree oil should never be swallowed. Tea tree oil in particular (derived from the Australian native plant Melaleuca alternifolia ) has been recognized for its efficacy against methicillin resistant S. aureus and has consequently been considered as an alternative treatment for mupirocin-resistant methicillinresistant S. aureus ²⁰ . However, despite the potential for novel agents such as tea tree oil, their acceptance and use in wound management will be limited until adequate safety and clinical efficacy data have been generated.

Current research going on tea tree oil like a project aims to provide preliminary data on whether the practice of washing wounds with a tea tree oil solution is beneficial in terms of eliminating anti-biotic resistant organisms, specfically MRSA, and whether it affects wound healing in a positive manner. The study will be conducted amongst Silver Chain domiciliary metropolitan clients receiving current wound care. A minimum of fourteen (and a maximum of 25) adults who are receiving wound care from Silver Chain for a wound that has been shown to be MRSA colonised will be recruited into the study and their wound washed at each dressing change with a tea tree oil wash. The outcomes assessed will include the wound healing rate as well as the microbiological evidence of MRSA colonisation level. ²¹

Pure Tea Tree Essential Oil Pharmacological Characteristics

Tea Tree is one of only two essential oils (Lavender being the other) which can be used neat on the skin in small amounts. Apply one or two drops directly to spots, cuts, insect bites, stings, blisters and viral problems such as warts, verrucae, cold sores, shingles and Chickenpox lesions. During prolonged or debilitating illness blend 3 - 6 drops of Tea Tree Oil in 2 teaspoons of vegetable carrier oilfor an immune boosting massage. To combat the spread of airborne germs during illness vapourise 8 drops of Tea Tree in an oil burner, or mix 20 drops with 200ml of spring water in a glass plant sprayer and spray directly into the air, shaking well before each use.

The use of Tea Tree in a steam inhalation can be a very effective method of obtaining relief from respiratory infections, cattarh, colds or flu. Add 5 drops to a bowl of boiling water cover the head with a towel and inhale the vapours for several minutes. 5 drops added to a warm bath can help relieve the symptoms of Thrush or Cystitis and can also induce sweating to lower a fever during illness. To relieve Athletes Foot or fungal infections of the nails add 3 - 5 drops of oil to a warm foot bath and soak the feet daily. Dry thoroughly with a clean towel, especially between the toes. Follow up with an application of Tea Tree Antiseptic Cream.To soothe mouth ulcers and sore gums, or to remedy bad breath, make up a mouthwash or gargle by diluting 3 drops of Tea Tree in a teaspoon of brandy. Stir into a glass of warm water and gargle or swish around the mouth.

To treat flea infestation in dogs, cats or rabbits prepare a repellent spray by diluting 2 drops of Tea Tree in 300ml (½ pint) of warm water. Brush the fur in the wrong direction and spray the coat with this solution, working from the tail to the head, avoiding the eyes. Brush the coat back into place and towel dry to remove excess spray. Repeat at 5 day intervals until clear. A natural anti-bacterial kitchen surface spray can be prepared by combining 60 drops of Tea Tree oil with 500ml of spring water in a plant sprayer. Other oils such as Lemon, Mandarin or Pine may be added for fragrance and to increase degreasing power. Shake well before each use and dry surfaces thoroughly before food preparation. (Not suitable for polished wood surfaces such as tabletops).
This preparation is also excellent for cleaning up after pets on kitchen floors. Chewing gum can be removed from hair or clothing with an application of neat Tea Tree oil.  Fungal Plant Diseases such as Mildew, Rust and Blackspot can be treated with Tea Tree oil which has anti-fungal properties.

Products

Melaleuca Tea Tree Oil Soap Bar

100% plant based cleansing bar contains both Tea Tree & Eucalyptus essential oils, selected for their deep cleansing, anti-microbal and anti-inflammatory properties. Oily skin or acne (caused by an over production of sebum by the sebaceous glands) and skin infections can be helped by the daily use of Tea Tree Oil Soap.
Use the cleansing bar morning & evening and pat the skin dry. Follow this with an application of Tea Tree Antiseptic Cream.Tea Tree oil soap is suitable for all skin types. It has a rich, creamy lather and can be used by anyone as a refreshing face, hand or bath soap.   

Melaleuca Tea Tree Oil Antiseptic Cream

Tea Tree contained in a versatile, non-greasy healing cream base. Pure Tea Tree essential oil is combined with Aloevera, Vitamin E, Sweet Almond oil and extracts of Lavender, Comfrey, Chamomile & Ginseng. This cream is readily absorbed and suitable for any skin type. Following facial cleansing with Tea Tree Oil Soapthose with oily skin or acne can benefit from a soothing application of Tea Tree Antiseptic Cream.

The soothing, cooling, anti-inflammatory properties of Tea Tree Oilmake this cream ideal for application after shaving or to itchy, inflammed skin, sunburn, rashes, Chicken Pox, or Shingles lesions.

The fungal skin infection Athletes Foot can be helped by the use of Tea Tree. Take a daily footbath using 3 - 5 drops of essential oil. Dry thoroughly and then massage Tea Tree Antiseptic Creaminto the soles of the feet, around the nails and between the toes.

Keep a jar of Tea Tree Antiseptic Cream in your first aid box for the treatment of cuts, grazes, minor wounds, blisters, insect bites etc.

Tea tree oil hydrogel

A study was undertaken to investigate the cooling and healing effect of different modalities: Melaleuca alternifolia Hydrogel (Levtrade International (Pty) Ltd.) was compared with tap water as a coolant following application onto a fresh deep partial thickness hot water burn in a porcine model. Four identical circular scalds were created on the backs of 10 pigs. One wound was not treated and served as a control. The other 3 wounds were either cooled with tap water (15 degrees C) or had Melaleuca Hydrogel dressing applied immediately, or after a 30 min delay. Intradermal temperatures were monitored in all wounds: preburn, during the burn and at regular intervals for 1 h. The wounds were biopsied for histological assessment. These samples were repeated at 24 h and 3 weeks. The mean decrease in final temperature at 1 h was in comparison to the preburn temperature; control +0.44 degrees C (i.e. a temperature increase); water -7.82 degrees C; Melaleuca Hydrogel -3.87 degrees C; Melaleuca Hydrogel after 30 min delay -2.67 degrees C. Clinical and histological assessment at 21 days indicated more rapid healing in both the Melaleuca Hydrogel and water-cooled burns compared with the untreated controls. Effective cooling of the burn wound and an increased rate of wound healing was achieved by both repeated tap water compresses and by immediate or delayed application of Melaleuca Hydrogel. Cooling is an effective means to reduce tissue damage and increase wound healing. ²²

Ongoing research

KawakamiEet al. indicate that the treatment of prostatic abscesses by aspiration of the purulent matter and injection of tea tree oil into the cavities is very effective in dogs. ²³

The study of Laplante KLon colonization of methicillin resistant Staphylococcus aureus (MRSA) commonly leads to infection by the same strain. We examined the activity of lysostaphin, mupirocin, and tea tree oil against clinical MRSA (n = 98) isolates. The result shows that Lysostaphin and tea tree oil may offer additional therapeutic options for the decolonization of MRSA where current treatment alternatives are limited. ²⁴

MondelloFet al. investigations on the antifungal properties of essential oil of Melaleuca alternifolia with reference to the treatment of vaginal candidiasis.and concluded that terpinen-4-ol could control C. albicans vaginal infections. The purified compound holds promise for the treatment of vaginal candidiasis, and particularly the azole-resistant forms. ²⁵

S McMahonMAet al. To investigate the effect of sub-lethal challenge with tea tree oil (TTO) on the antibiotic susceptibility profiles of significant human pathogens and commensals. They concluded that may be an effective antimicrobial agent when appropriately used at bactericidal concentrations, its application at sub-lethal concentrations may contribute to the development of antibiotic resistance in human pathogens. ²⁶

Brady Aet al. study susceptibility of Staphylococcus aureus [meticillin-resistant (MRSA) and methicillin sensitive (MSSA)] and coagulase negative staphylococci (CoNS), which respectively form part of the transient and commensal skin flora, to tea-tree oil (TTO) was compared using broth microdilution and quantitative in vitro time-kill test methods. Results suggest that TTO exerts a greater bactericidal activity against biofilm grown MRSA and MSSA isolates than against some biofilm grown CoNS isolates. ²⁷

Giordani Cet al. study effects of TTO on actual MDR (multi drug resistant) melanoma cell membranes using flow cytometry analysis (FCA) and freeze-fracturing transmission electron microscopy. They concluded that effect exerted on MDR melanoma cells is mediated by the interaction with the fluid DPPC phase, rather than with the more organized "rafts" and that this interaction preferentially influences the ATP-independent antiapoptotic activity of P-gp likely localized outside "rafts". ²⁸

ReichlingJet al. investigate the capability of terpinen-4-ol, the main compound of Australian tea tree oil (TTO), to permeate human skin. The flux values of three different semisolid preparations with 5% TTO showed the rank order semisolid O/W emulsion (0.067 microl/cm2 h) > white petrolatum (0.051 microl/cm2 h) > ambiphilic cream (0.022 microl/cm2 h). ²⁹

PapadopoulosCJet al. study thirty isolates of Pseudomonas aeruginosa, 15 isolates of Pseudomonas putida and 11 isolates of Pseudomonas fluorescens were tested for susceptibility to tea tree oil (TTO), the essential oil of Melaleuca alternifolia, and the components terpinen-4-ol, alpha-terpineol, cineole, gamma-terpinene and rho-cymene. The MIC90 of TTO for all isolates tested was 4% (v/v) or less. Susceptibility to components tested varied between species. CONCLUSIONS: Pseudomonas species are susceptible to TTO and some of its components although they are less susceptible than many other bacteria tested previously. ³⁰

Adverse effects

While tea tree oil can be applied to minor cuts and scrapes, use caution for more extensive areas of broken skin or areas affected by rashes not due to fungus. The oil may burn if it gets into the eyes, nose, mouth, or other tender areas. Some people have allergic reactions, including rashes and itching, when applying tea tree oil ³¹ . For this reason, only a small amount should be applied when first using it. Tea tree oil should never be swallowed, as it may cause nerve damage and other problems.

Conclusion

The tea tree oil can be used successfully in wound healing due to its good antibacterial and antiseptic activity. It also possesses soothing, cooling, anti-inflammatory properties, which also help to recover the wound.

References:

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Table 1: Summary of medicinal uses of Tea Tree Oil

Table 2: Characteristics of tea tree oil

Table 3: Typical Analysis by Gas Chromatography (Distillation Method:  Simple Steam Distillation from the Leaves)