Melaleuca leucadendron cajaputi, commonly known as the Cajaputi tree or white tea tree, is a species of Melaleuca native to northern Australia and New Guinea. It is valued for its essential oil, which has various therapeutic and medicinal uses. The tree is characterized by its distinctive papery bark, aromatic leaves, and small, white or cream-colored flowers. The essential oil derived from this tree is known for its antimicrobial and anti-inflammatory properties.

Botanical Classification

• Kingdom: Plantae
• Order: Myrtales
• Family: Myrtaceae
• Genus: Melaleuca
• Species: M. leucadendron
• Variety: M. leucadendron cajaputi

Plant Characteristics

Melaleuca leucadendron cajaputi is a medium-sized evergreen tree that can reach heights of up to 20 meters (65 feet). It has narrow, lance-shaped leaves that are aromatic when crushed. The bark is thin and papery, often peeling in strips. The tree produces small, fluffy white or cream-colored flowers that bloom in clusters. It thrives in tropical to subtropical climates and is commonly found in wetlands and coastal areas.

Chemical Composition and Structure

The essential oil of Melaleuca leucadendron cajaputi contains several key compounds:

• Cineole (Eucalyptol): Known for its expectorant and antiseptic properties.
• Terpinen-4-ol: Exhibits antimicrobial and anti-inflammatory effects.
• Alpha-Terpineol: Contributes to its pleasant fragrance and has antimicrobial properties.
• Limonene: Provides additional antimicrobial and antioxidant benefits.

Cultivation

Melaleuca leucadendron cajaputi grows best in well-drained, sandy or loamy soils. It requires full sun and regular watering, particularly during dry periods. The tree is propagated from seeds or cuttings and benefits from occasional pruning to maintain shape and encourage bushier growth. It is suited to tropical and subtropical climates and is generally hardy to mild frost.

Uses and Benefits

• Essential Oil: The oil extracted from Melaleuca leucadendron cajaputi is used for its antiseptic, anti-inflammatory, and expectorant properties. It is employed in aromatherapy and as a natural remedy for respiratory conditions, skin infections, and minor wounds.

• Cosmetic: The essential oil is used in various cosmetic products for its antimicrobial properties and pleasant fragrance. It is included in skincare products to help with acne and other skin issues.

INCI Functions:

Skin conditioning agent. It is the mainstay of topical skin treatment as it has the function of restoring, increasing or improving skin tolerance to external factors, including melanocyte tolerance. The most important function of the conditioning agent is to prevent skin dehydration, but the subject is rather complex and involves emollients and humectants that can be added in the formulation.

Applications

• Aromatherapy: Utilized in diffusers and inhalers to relieve respiratory issues and promote relaxation.

• Medicinal: Used in topical treatments for minor wounds, infections, and inflammatory conditions.

Environmental and Safety Considerations

Melaleuca leucadendron cajaputi is generally safe for use in aromatherapy and topical applications. However, essential oils should be used with caution, as they can cause skin irritation in some individuals. It is important to follow proper dilution guidelines and conduct a patch test before widespread use. Sustainable harvesting practices should be employed to ensure the health of wild populations and prevent overexploitation.

Bibliografia__________________________________________________________________________

Surh J, Yun JM. Antioxidant and Anti-inflammatory Activities of Butanol Extract of Melaleuca leucadendron L. Prev Nutr Food Sci. 2012 Mar;17(1):22-8. doi: 10.3746/pnf.2012.17.1.022. PMID: 24471059; PMCID: PMC3866767.

Abstract. Melaleuca leucadendron L. has been used as a tranquilizing, sedating, evil-dispelling and pain-relieving agent. We examined the effects of M. leucadendron L. extracts on oxidative stress and inflammation. M. leucadendron L. was extracted with methanol (MeOH) and then fractionated with chloroform (CHCl3) and butanol (BuOH). Antioxidant activity of the MeOH extract and BuOH fraction were higher than that of both α-tocopherol and butyrated hydroxytoluene (BHT). Total phenol content in the extracts of M. leucadendron L., especially the BuOH fraction, well correlated with the antioxidant activity. The anti-inflammatory activity of BuOH extracts were investigated by lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production, and cyclooxygenase-2 (COX-2) expression in RAW 264.7 macrophages. The BuOH fraction significantly inhibited LPS-induced NO and PGE2 production. Furthermore, BuOH extract of M. leucadendron L. inhibited the expression of COX-2 and iNOS protein without an appreciable cytotoxic effect on RAW264.7 cells. The extract of M. leucadendron L. also suppressed the phosphorylation of inhibitor κBα (IκBα) and its degradation associated with nuclear factor-κB (NF-κB) activation. Furthermore, BuOH fraction inhibited LPS-induced NF-κB transcriptional activity in a dose-dependent manner. These results suggested that M. leucadendron L. could be useful as a natural anti-oxidant and anti-inflammatory resource.

Sousa LRD, Santos MLDC, Sampaio LS, Faustino CG, Guigueno MLL, Freitas KM, Lopes MTP, Mota GCF, Dos Santos VMR, Seibert JB, Amparo TR, Vieira PMA, Santos ODHD, de Souza GHB. Nanoemulsified Essential Oil of Melaleuca leucadendron Leaves for Topical Application: In Vitro Photoprotective, Antioxidant and Anti-Melanoma Activities. Pharmaceuticals (Basel). 2024 Jun 2;17(6):721. doi: 10.3390/ph17060721. 

Abstract. Melanoma, primarily caused by solar ultraviolet (UV) radiation, can be prevented by the use of sunscreens. However, the use of synthetic sunscreens raises environmental concerns. Natural compounds with antioxidant photoprotective properties and cytotoxic effects against cancer cells can be promising for the prevention and treatment of melanoma with less environmental effect. This study focuses on Melaleuca leucadendron essential oil (EO) for photoprotection and antitumor applications. EO was hydrodistilled from M. leucadendron leaves with a 0.59% yield. Gas chromatography-mass spectrometry detected monoterpenes and sesquiterpenes. Nanoemulsions were prepared with (NE-EO) and without EO (NE-B) using the phase inversion method, showing good stability, spherical or oval morphology, and a pseudoplastic profile. Photoprotective activity assessed spectrophotometrically showed that the NE-EO was more effective than NE-B and free EO. Antioxidant activity evaluated by DPPH and ABTS methods indicated that pure and nanoemulsified EO mainly inhibited the ABTS radical, showing IC50 40.72 and 5.30 µg/mL, respectively. Cytotoxicity tests on L-929 mouse fibroblasts, NGM human melanocyte, B16-F10 melanoma, and MeWo human melanoma revealed that EO and NE-EO were more cytotoxic to melanoma cells than to non-tumor cells. The stable NE-EO demonstrates potential for melanoma prevention and treatment. Further research is required to gain a better understanding of these activities.

Valdés AF, Martínez JM, Lizama RS, Vermeersch M, Cos P, Maes L. In vitro anti-microbial activity of the Cuban medicinal plants Simarouba glauca DC, Melaleuca leucadendron L and Artemisia absinthium L. Mem Inst Oswaldo Cruz. 2008 Sep;103(6):615-8. doi: 10.1590/s0074-02762008000600019.

Abstract. In the present study, an extensive in vitro antimicrobial profiling was performed for three medicinal plants grown in Cuba, namely Simarouba glauca, Melaleuca leucadendron and Artemisia absinthium. Ethanol extracts were tested for their antiprotozoal potential against Trypanosoma b. brucei, Trypanosoma cruzi, Leishmania infantum and Plasmodium falciparum. Antifungal activities were evaluated against Microsporum canis and Candida albicans whereas Escherichia coli and Staphylococcus aureus were used as test organisms for antibacterial activity. Cytotoxicity was assessed against human MRC-5 cells. Only M. leucadendron extract showed selective activity against microorganisms tested. Although S. glauca exhibited strong activity against all protozoa, it must be considered non-specific. The value of integrated evaluation of extracts with particular reference to selectivity is discussed.