Chemical Composition and Potential of Eucalyptus camaldulensis Dehnh. Essential Oil and Its Major Components as Anti-inflammatory and Anti-leishmanial Agent

Abstract

The present study evaluated cytotoxic, anti-inflammatory, and anti-leishmanial properties of essential oil (EO) from fresh foliage of Eucalyptus camaldulensis Dehnh., and its major constituent compounds− 1,8-cineole, β-pinene and α-pinene. The chromatographic analysis of the hydrodistilled EO using gas chromatography-mass spectrometry (GC/MS) revealed the presence of 25 compounds which constituted 99.45% of EO. The EO comprised of 36% monoterpenoid hydrocarbons and 22.3% oxygenated monoterpenes. The most abundant constituent was 1,8-cineole (17.1%) followed by β-pinene (16.5%). In addition, significant quantities of β-eudesmol (10.9%), limonene (9.5%), and α-pinene (7.9%) were observed. Cell cytotoxicity concentration was observed to be highest in 1,8-cineole (CC50 > 640 µg/mL), followed by α-pinene (CC50 > 320 µg/mL), β-pinene (CC50 > 160 µg/mL) and EO (CC50 > 20 µg/mL). Investigation of anti-inflammatory potential by carrageenan-induced rat paw edema model revealed maximum inhibition in α-pinene (85.6% at 500 mg/kg body wt. and 81% at 250 mg/kg body wt.) after 3 h, which was comparable to indomethacin (positive control). Among the EO and its components, β-pinene exhibited maximum anti-leishmanial potential with IC50 of 2.57 ± 0.15 mL. The study concluded that E. camaldulensis EO possesses significant anti-inflammatory and anti-leishmanial activity, thus suggesting the use of EO and its major constituents as a green drug that is a safer alternative to synthetic compounds.