Extraction et caractérisation de l’huile essentielle d’Eucalyptus radiata et activités biologiques

Abstract

Eucalyptus radiata, belonging to the Myrtaceae family, is a tree native to Australia, widely cultivated for its leaves rich in essential oil. The latter is traditionally used to relieve respiratory ailments, thanks to its expectorant, antiseptic and decongestant properties. In this study, the essential oil was extracted from the leaves by Clevenger-type hydrodistillation, with a yield of 0.32 ± 0.06 %. Analysis by gas chromatography coupled with mass spectrometry (CPG/MS) made it possible to identify 17 compounds, of which 1,8-cineole (or eucalyptol) is the majority, representing 53.4% of the total. The antioxidant activity evaluated by the DPPH method showed a good scavenging power of free radicals, with an IC₅₀ of 0.294 mg/ml. The anti-inflammatory activity, determined by the inhibition of the thermal dénaturation of albumin, reached 72% at 20 mg/ml. Moreover, the oil showed a notable antimicrobial activity, with inhibition zones of 16 mm for Bacillus subtilis, 13 mm for Staphylococcus aureus and 12 mm for Candida albicans.These results allowed the formulation of an antiseptic oral solution at two concentrations (1% and 2%). This, Eucalyptus radiata essential oil is positioned as a promising natural agent for targeted medicinal and hygienic applications.