OBJECTIVES The essential oil of Melaleuca alternifolia (tea tree oil) and its components have antimicrobial activity against a wide range of Gram-positive and Gram-negative bacteria, fungi and viruses. The mechanism(s) by which Pseudomonas aeruginosa NCTC 10662 maintains a decreased susceptibility to tea tree oil and components was investigated. RESULTS Ethylene diamine tetraacetic acid enhan...

Background Terpenes are important mediators of plant-environment interactions as well as often being economically important. Terpenes are biosynthesized via two spatially separate pathways: the MEP pathway in the plastid, the site of monoterpene biosynthesis and the MVA pathway in the cytosol, the site of sesquiterpene biosynthesis (McGarvey and Croteau 1995; Eisenreich et al. 1998; Rohmer 1999...

Phytomedicine such as tea tree (melaleuca) oil have become increasingly popular in recent decades. This essential oil has been used for almost 100 years in Australia but is now available worldwide both as neat oil and as an active component in an array of products. The primary uses of tea tree oil have historically capitalized on the antiseptic, antifungal, antiviral and anti-inflammatory actio...

BACKGROUND Tea tree oil is the essential oil steam-distilled from Melaleuca alternifolia, an Australian native plant. In recent years it has become increasingly popular as an antimicrobial for the treatment of conditions such as tinea pedis and acne. OBJECTIVES To investigate the anti-inflammatory properties of tea tree oil on histamine-induced weal and flare. METHODS Twenty-seven volunteer...

Holoparasites are nonphotosynthetic plants that acquire all resources from hosts. The holoparasite Cuscuta gronovii is native to much of the US with a broad host range including Verbesina alternifolia, an understory perennial. Both species grow in moderate to moist soils and occur in habitats that may experience prolonged or episodic drought. We applied the Wise-Abrahamson Limiting Resource Mod...

Medicinal tea tree (Melaleuca alternifolia) leaves contain large amounts of an essential oil, dominated by monoterpenes. Several enzymes of the chloroplastic methylerythritol phosphate (MEP) pathway are hypothesised to act as bottlenecks to the production of monoterpenes. We investigated, whether transcript abundance of genes encoding for enzymes of the MEP pathway were correlated with foliar t...

There has recently been a significant increase in the use of therapeutically active compounds extracted from plants as opposed to chemically synthesised drugs. The demand for natural products is increasing and in many cases currently exceeds supply. The flora of New Zealand and Australia is rich in unique species, however, very few of these native plants have been tested for medicinal constitue...

In the present study, we have evaluated the in vitro antibacterial activity of essential oils from Origanum vulgare, Thymus vulgaris, Lavandula angustifolia, Mentha piperita, and Melaleuca alternifolia against 32 erythromycin-resistant [Mininum Inhibitory Concentration (MIC) ≥1 μg/mL; inducible, constitutive, and efflux-mediated resistance phenotype; erm(TR), erm(B), and mef(A) genes] and cell-in...

This study was conducted to determine the frequencies at which single-step mutants resistant to tea tree oil and rifampicin occurred amongst the Gram-positive organisms Staphylococcus aureus, Staphylococcus epidermidis and Enterococcus faecalis. For tea tree oil, resistance frequencies were very low at <10(-9). Single-step mutants resistant to tea tree oil were undetectable at two times the min...

The experiment was conducted during the year 2019-21 at Horticulture Research Station, OUAT, Bhubaneswar laid out in Randomized Block Design (RBD) with 4 replications. 6 modules. growth parameters like plant height (75.36 cm and 133.52 cm), spread E-W (46.41 74.09 N-S (39.98 70.72 stem diameter (15.97 32.94 length of branch (31.68 58.34 number primary branches (19.61 31.42), secondary (17.29 36...