Methyl Eugenol, 1,8-Cineole and Nerolidol Rich Essential Oils with their Biological Activities from three Melaleuca Species Growing in Tarai Region of North India

The essential oils from the fresh leaves of three Melalecua spp. viz; Melaleuca leucadendron (L.) Melaleuca linariifolia Sm. and Melaleuca bracteata F. Muell. growing in Tarai region of North India were analyzed by a combination of gas chromatography/mass spectrometry. The analysis revealed the presence of several constituents of industrial and pharmacological importance. M. leucadendron essential oil was found to be dominated by E-nerolidol (85.7%) rich chemotype. 1,8-cineole (61.1%) along with significant presence of a-terpineol (12.3%), alpha-pinene (4.0%), beta-myrcene (3.8%), and E-caryophyllene (1.7%) were identified in the essential oil from M. linariifolia Similarly M. bracteata was dominated by the presence of phenylpropanoids viz; methyl eugenol (74.8%) and methyl cinnamate (8.0%). The essential oils were studied for their in-vitro antioxidant, anti-inflammatory and antimicrobial potential. All the oils revealed potential antioxidant activity with maximum in M. bracteata essential oil. All the oils exhibited significant antibacterial activity against Bacillus megaterium, Staphylococcus aureus, Escherichia coli,Salmonella typhimurium and anti-fungal activity against phytopathogenic fungi Fusarium oxysporum, Sclerotinia sclerotiorum, Exserohilum turcicum and Curvularia lunata. The observations from present study suggest further cultivation of Melaleucas and its commercialization as industrial crops.

Automated summary

The essential oils from three Melaleuca spp. in North India were analyzed, revealing important industrial and pharmacological constituents. These oils showed potential antioxidant, anti-inflammatory, and antimicrobial activities, with M. bracteata essential oil exhibiting the highest antioxidant activity. This study suggests further cultivation and commercialization of Melaleucas as industrial crops.