Phytochemical Characterization, Antioxidant, Anti-Inflammatory, Anti-Nociceptive and Antimicrobial Properties of the Seed Essential Oil of Eucalyptus tereticornis

The seed essential oils of Eucalyptus tereticornis possess strong medicinal properties. The aim of the current research study was to determine the phytochemicals and medicinal properties of the seed essential oil of E. tereticornis from Nigeria. The 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. The GC and GC-MS analyses revealed the presence of 33 phytochemicals making up 97.2% of the total percentage composition of the essential oil. The most abundant component were α-selinene (15.5%), α-pinene (13.0%), 1,8-cineole (10.5%), β-pinene (8.0%), α-limonene (8.0%), α-terpineol (7.0%) ledol (5.0%) and palmitic acid (5.0%). The TPC was 206.68±0.00 µgmg^-1 GAE. The DPPH IC₅₀ and AAI values of the essential oil were 2.0 µgml^-1 and 20.0. The essential oil was capable of scavenging free radicals in a range of 62.7-67.6%, while the reduction antioxidant potential was EC₅₀: 5.0 µgml^-1. The essential oil gave high anti-inflammatory with value of 99.76% and antinociceptive properties by inhibition in both neurogenic (57.81%) and inflammatory pain (47.86%). The essential oil was active against all the tested bacteria with high zones of inhibition (11.0-30.0 mm). The seed essential oil of E. tereticornis has potential medicinal compounds that may be of great use for the development of natural drugs