MANUKA, Leptospermum scoparium

Latin name : Leptospermum scoparium

Distilled part: leaves

Origin: New Zealand

Properties: antibacterial +++, antifungal +++, antiviral + + +, cicatrisant, atmospheric disinfectant, skin regenerative, antispasmodic

Indications: gram + bacteria: Staphyloccocus (aureus, epidermidis), Streptococcus (faecalis, agalactiae), so-called Gram – bacteria : Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae, Candida albicans, Tricophyton rubrum, Aspergillus niger, Microsporum canis, mentagrophytes, respiratory tract infections, ORL infections, various skin infections (acne), psoriasis, herpes I and II, oral hygiene: gingivitis, halitosis, ulcers

Contraindications None at physiological doses.

Our expert’s opinion:

An essential oil with an exotic name but many benefits!

Author: Maurice Nicole, NDA

Manuka is one of the most widespread native plants in New Zealand, with up to 11 different chemotypes.

It is a slender tree growing up to 8 m tall. The foliage is gray-green in color, and the leaves are small with sharp needles. The flowers, small and pink to red in color, resemble miniature roses. A first abundant flowering occurs in winter, followed by a second flowering in summer.

Manuka is the Māori term for L. scoparium. The plant is sometimes referred to as “Ti-tree” but should not be confused with the Australian Tea Tree. This tree has long been valued for its healing properties by the Māori people (the indigenous people of Aotearoa, New Zealand).

Manuka essential oil is obtained by steam distillation of the Leptospermum scoparium leaves, harvested primarily in the East Cape region, which is the easternmost point of New Zealand’s main islands. This essential oil is distinguished by the presence of 20% to 30% triketones (leptospermone, isoleptospermone, and flavesone), which give it its unique antimicrobial properties.

Of the 11 chemotypes identified, it is the most widely marketed and studied. This chemotype is also found in the Marlborough region, another region of New Zealand located in the northeastern corner of the South Island.

ANTIBACTERIAL PROPERTIES

This particular chemotype has been shown to be 20 to 30 times more effective than Melaleuca alternifolia essential oil against Gram-positive bacteria such as Staphylococcus aureus, MRSA, S. epidermidis, S. faecalis, and S. epidermidis. S. agalactiae, Micrococcus luteus, Sarcina lutea, Bacillus subtilis, Listeria monocytogenes, and many others, including those resistant to antibiotics. Although several studies report that this essential oil has negligible activity against Gram-negative bacteria such as E. coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Proteus vulgaris, the study by Porter and Wilkins showed that it could inhibit the Gram-negative bacteria E. coli and Pseudomonas aeruginosa as well as Candida albicans.

ANTI-ACNE PROPERTIES

Several studies and clinical trials have confirmed the effectiveness of this essential oil in treating acne due to its antimicrobial (against Propionibacterium acnes), anti-seborrheic, astringent, and anti-inflammatory properties.

ORAL HEALTH

Manuka essential oil has numerous applications in oral health.

When used as a mouthwash, it helps patients with head and neck cancers protect their oropharyngeal cavity by reducing inflammation and mucositis caused by radiation therapy.

This essential oil is capable of inhibiting all cariogenic bacteria and those responsible for periodontal diseases, such as Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum, Streptococcus mutans, and Streptococcus sobrinus. It can also inhibit biofilm formation and is therefore ideal for preventing and treating dental plaque. Takarada’s study (2005) suggests the use of essential oils, including manuka, for maintaining oral health and treating halitosis.

ANTIFUNGAL PROPERTIES

Several studies have demonstrated its antifungal activity against various species of fungi commonly responsible for dermatophytoses (skin infections): Trichosporon mucoides, Malassezia furfur, Candida albicans, Microsporum canis, Trichophyton rubrum, Trichophyton terreum, and Trichophyton mentagrophytes.

ANTIVIRAL PROPERTIES

Reichling et al. (2005) demonstrated the significant antiviral activity of this essential oil against the herpes viruses HSV-1 and HSV-2, including strains resistant to acyclovir. It directly neutralizes free viruses outside cells. Once inside the cells, the essential oil cannot prevent viral replication, with the exception of the HSV-1 virus, where a reduction in viral replication of approximately 40% was observed. Subsequent studies by Sojka (2005), Schnitzler et al. (2008), and Magsombol (2012) confirmed Reichling’s findings.

ANTISPASMODIC PROPERTIES

Lis-Balchin & Heart (1995, 1998) & Lis-Balchin et al. (2000), after studying the effects of this essential oil on the ileum of the guinea pig, the biventer cervicis (skeletal muscle) of the chick, and the diaphragm and uterus of the rat in vitro, concluded that manuka essential oil produces a spasmolytic effect on smooth and skeletal muscles. These studies support its use as a muscle relaxant and decontractant in aromatherapy.

ANTIOXIDANT AND ANTI-AGING PROPERTIES

Lis-Balchin et al (1996, 2000) demonstrated the antioxidant activity of manuka essential oil and found it superior to that of Tea-Tree (Melaleuca alternifolia) essential oil.
Kwon et al (2013) evaluated its UV-B photoprotective effect and demonstrated that, depending on the dose used, topical application prevents skin thickening and wrinkling and suppresses UV-B-induced skin inflammation by inhibiting inflammatory cytokines.

ANTI-INFLAMMATORY PROPERTIES

Following their investigation, Chen et al. (2014) confirmed the anti-inflammatory effects of manuka essential oil; They determined that it inhibits tumor necrosis factor alpha (TNF-α), a pro-inflammatory cytokine, without blocking interleukin-4 (IL-4), an anti-inflammatory cytokine capable of inhibiting the pro-inflammatory cytokines interleukin-1 (IL-1) and interleukin-6 (IL-6). These results suggest that this essential oil is well-suited for treating skin lesions and infected wounds, in addition to serving as an active ingredient in skin care products.

The β-triketones in manuka essential oil are used in anti-dandruff shampoos due to their antifungal activity against Malassezia, a species of yeast that proliferates on the scalp and in sebum.

ACARICIDAL PROPERTIES

Its acaricidal activity was established following the work of Jeong (2008) and Jeong et al. (2009), who demonstrated that the triketones from L. scoparium kill three species of mites: Dermatophagoides farinae, D. pteronyssinus, and Tyrophagus putrescentiae.

SUGGESTED FORMULA AS A TOOTHPASTE TO PREVENT TARTAR AND FIGHT BAD BREATH

Essential oils:

• Leptospermum scoparium x 3 ml
• Laurus nobilis x 1 ml
• Mentha x piperita x 1 ml

White clay, purchase the desired amount

1. Toothpaste: sprinkle a pinch of white clay onto a damp toothbrush, add 1 drop of the essential oil blend, and gently brush your teeth and gums.
2. Bad breath: Place 1–2 drops on a DGL licorice tablet and chew several times a day, or add 5 drops to a small amount of water, shake, and then rinse your mouth with the mixture.