Chemical Composition, Antioxidant, and Antibacterial Activities of the Essential Oil and Methanol Extracts ofEucalyptus largiflorensF. Muell

Abstract

This study was designed to examine the chemical composition of essential oil and in vitro antioxidant and antimicrobial activity of the essential oil and methanol extracts of Eucalyptus largiflorens F. Muell. The chemical composition of the hydrodistilled essential oil of the leaves of E. largiflorens was analyzed by gas chromatography and gas chromatography/mass spectrometry. The main constituents of the oil were found to be 1,8-cineole (23.1%), cryptone (15.1%), 4-allyloxyimino-2-carene (11.2%), and 4-terpineol (9.6%). The essential oil showed strong antibacterial activity against the studied microorganisms, except for P. aeruginosa, while polar subfraction of methanol extract had moderate antimicrobial activity and the nonpolar subfraction of methanol extract did not show any antimicrobial activity. In contrast, the extract showed better activity than the essential oil in antioxidant activity assays employed, e.g., in a 2,2-diphenyl-1-picryl-hydrazyl system. Also, the polar subfraction of methanol extract (15.1 ± 0.7 µg/ml) showed the highest radical-scavenging activity. In the second case, the inhibition capacity (%) of the nonpolar subfraction (92.7% ± 2.5) was found to be the stronger one. Finally, the total amounts of phenol constituents in the polar subfraction (142.6 ± 0.9 µg/mg), nonpolar subfraction (68.6 ± 0.4 µg/mg), and the oil (36.0 ± 0.6 µg/mg) were determined.

Antifungal Effect of Plant Essential Oils on Controlling Phytophthora Species

“…Dev et al (2011) indicated eugenol (61.7%), isopropyl palpitate (11.3%) and 2,3-dihydroxy propyl elaidate (5.1%) as major chemical compounds among O. basilicum oils. Differences in composition of essential oils might have been derived by harvest time, as well as local, climatic and seasonal factors (Rahimi-Nasrabadi et al, 2013). …”

Effects of essential oils of lemon grass, Cymbopogon citratus and the Mexican marigold, Tagetes minuta on mortality and oviposition in adult sandflies, Phlebotomus duboscqi

“…Gupta et al [62] found that the main components of C. citratus essential oil were dominated by citral (77.8%), limonene + traces of eucalyptol (4.0%), geraniol (2.7%), 6 methyl-5hepten-2-one (2.4%) and geranyl acetate (1.1%). The differences in the composition of the essential oil might have been derived both from harvest time and local, climatic and seasonal factors, or it may be hypothesized that these samples belong to a different chemotype [63].…”

Evaluación de la Actividad Antioxidante de Aceites Esenciales de Eucaliptos Cultivados en Colombia

“…Los fenoles totales estuvieron por encima de los reportados por la literatura para otras especies de eucalipto, teniendo en cuenta que las densidades de los aceites esenciales de las especies estudiadas se encuentran entre 0.88-0.91 g/ml. Dezsi et al, (2015) determinaron fenoles totales para el aceite esencial de E. globulus de 235.87±4.38 mg/g; Rahimi-Nasrabadi et al, (2013) para el aceite esencial de E. largiflorens encontraron fenoles totales constituyentes en la subfracción polar de 142.6±0.9 μg/mg, subfracción no polar 68.6±0,4 mg/g y en el aceite esencial de 36,0±0,6 mg/g. En la figura 6 se observa que la mayor capacidad antioxidante al reducir un complejo férrico a su forma ferrosa la presenta la muestra de E. camaldulensis de Chiriguaná.…”