Eucalyptus camaldulensis var. nancy and Eucalyptus camaldulensis var. petford Seed Essential Oils: Phytochemicals and Therapeutic Potentials

Abstract

Eucalyptus camaldulensis essential oils are aromatherapy agents in medicine. This study examined the phytochemicals and therapeutic activities of the seed essential oils of E. camaldulensis var. nancy and E. camaldulensis var. petford from Nigeria. The seed essential oil was extracted by hydrodistillation and analyzed using GC and GC-MS. TPC, antioxidant, anti-inflammatory, antinociceptive and antimicrobial activities were measured by Folin-Ciocalteu’s, DPPH, FRAP, carrageenan, formalin and agar-well diffusion methods respectively. GC and GCMS analyses of the essential oils led to the identification of 23 and 15 constituents representing 99.2% and 98.5% of the oil of E. camaldulensis var. nancy and E. camaldulensis var. petford, respectively. The main components in the seed essential oils of E. camaldulensis var. nancy and E. camaldulensis var. petford was 1,8-cineole (40.8%) and (52.0%) respectively. The TPC values of the oils were 156.25 ± 0.00 and 167.93 ± 0.00 µg GAE/mg respectively. The seed essential oils achieved optimum antioxidant potentials with IC50 values of 3.50 µgml-1. The seed essential oils have high reducing antioxidant activities, with EC50 values of 5.0 µgml-1 in the two varieties. The essential oils showed significant anti-inflammatory properties with oedema inhibitory percentages of 87.50% and 43.75% respectively and antinociceptive potential with inhibitory percentage at 70.52% and 80.52% in phase I (neurogenic), as well as 99.99% and 41.03% in phase II (anti-inflammatory). The seed essential oils showed efficient antibacterial activities with their zones of inhibitions values ranging between 13-24 mm at 1000-10 µgml-1. The results from this study revealed that the two seed essential oils have potentials as the therapeutic agents.