Lemon Myrtle
Scientific Name(s): Backhousia citriodora F. Muell.
Common Name(s): Lemon myrtle, Sweet verbena myrtle
Medically reviewed by Drugs.com. Last updated on Aug 5, 2021.
Clinical Overview
Use
The leaves and flowers of lemon myrtle are used in tea blends and beverages, biscuits, breads, confectionery, pasta, syrups, liqueurs, flavored oils, packaged fish (salmon), and dipping and simmer sauces. Topical 10% solution of lemon myrtle essential oil showed a 90% reduction of symptoms in children treated for Molluscum contagiosum. The leaf paste, essential oil, and hydrosols have antibacterial and antifungal activity against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, methicillin-resistant S. aureus (MRSA), Aspergillus niger, Klebsiella pneumonia, and Cutibacterium acnes. The Complementary Medicines Evaluation Committee (CMEC) of the Australian Therapeutic Goods Administration (TGA) reported the proposed use as an antiseptic therapy in the treatment of pimples and acne. B. citriodora leaf oil is about 98% citral.
Dosing
3 cups per day of 2 to 4 mL of a 1% alcoholic solution; 0.18 mg/cm2 of 1% lemon myrtle oil applied topically at exposure durations of 8 hours has been used as a topical antimicrobial. Two lemon myrtle leaves in 1 L of water have been used as a beverage.
Contraindications
Contraindications have not yet been identified.
Pregnancy/Lactation
Information regarding safety and efficacy in pregnancy and lactation is lacking.
Interactions
None documented.
Adverse Reactions
Research reveals no information regarding adverse reactions.
Toxicology
When 18.29 mg/cm2 of the essential oil is applied to the skin for 1 to 12 hours, a reduction in cellular functioning, loss in integrity, loss of cellular vacuolation, cellular necrosis, and lower solubility of the stratum corneum were documented. When 0.18 mg/cm2 of the essential oil was applied to the skin for 8 hours, the damage due to the citral component affected only epidermal cells. Oil of lemon myrtle was toxic to the hepatocarcinoma-derived human cell line (HepG2), F1-73 (a fibroblast cell line derived from healthy skin), and primary cell cultures of human skin fibroblasts. Cytotoxicity 50% inhibitory concentration (IC50) values ranged from 0.008% to 0.014% (w/v) at 4 hours to 0.003% to 0.012% (w/v) at 24 hours of exposure. The no-observed-adverse-effect level (NOAEL) for lemon myrtle oil was calculated as 0.5 mg/L at 24 hours of exposure, and the reference dose was determined as 0.01 mg/L. Therefore, lemon myrtle 1% oil was low in toxicity and could be safely used in topical antimicrobial products. The majority of research has been conducted on the compound citral as a common ingredient. Citral and citral oil are considered safe at a 1% dilution and has GRAS (generally recognized as safe) status by the US Federal Drug Administration.
Scientific Family
- Myrtaceae
Botany
B. citriodora (lemon myrtle) is a small genus with 6 species located in tropical regions of eastern Queensland and northeastern New South Wales, Australia.
Backhousia is a tree that grows up to 20 m, but in cultivation rarely exceeds 5 m. Leaves are opposite, glabrous, lanceolate, and dark green, and measure 100 mm. The fruit is a dry indehiscent that splits into 2 chambers.Hegarty 2001, Konczak 2010, Pengelly 1991 Lemon myrtle can be cultivated successfully in cooler areas when young plants are protected from frost.Ryder 2005 This hardy plant tolerates all soils except those that do not drain well. It...
