%0 Journal Article %T Phytochemical Profile and <i>In Vitro</i> Antioxidant Properties of Essential Oils from Powder Fractions of <i>Eucalyptus camaldulensis</i> Leaves %A Venant Donald Noumi %A Richard Marcel Nguimbou %A Marthe Valentine Tsague %A Markusse Deli %A Sandrine Rup-Jacques %A Dicko Amadou %A Elie Njantou Baudelaire %A Selestin Sokeng %A Nicolas Yanou Njintang %J American Journal of Plant Sciences %P 329-346 %@ 2158-2750 %D 2021 %I Scientific Research Publishing %R 10.4236/ajps.2021.123021 %X Dried leaves of Eucalyptus camaldulensis were finely grinded and fractionated by sieving into four granulometric classes (<100 ¦Ěm, 100 - 200 ¦Ěm, 200 - 355 ¦Ěm and >355 ¦Ěm). The obtained powder fractions were used for essential oil (EO) extraction by hydrodistillation and their phytochemical profile and in vitro antioxidant activities were evaluated. The mother powder (unsieved powder) was used for comparison. Particle size exerted a significant influence (p < 0.05) on the phytochemical composition and in vitro antioxidant properties of the EOs. Comparatively, the mother powder had the highest contents of ¦Á-pinene (55.6%), camphene (3.4%) and limonene (3.7%), while 1,8-cineole (26.6% and 22.4%), exo-fenchol (5.6% and 3.5%), ¦Á-campholenol (4.2% and 3.4%), L-trans-pinocarveol (5.5% and 2.7%), L-borneol (12.6% and 6.8%) and ¦Á-terpineol (16.4% and 7.6%) are the main compounds of EOs from the <100 ¦Ěm and 100 - 200 ¦Ěm fractions, respectively. The antioxidant activities of the EOs revealed higher radical-scavenging activities DPPH (90.62% and 70.46%) and ABTS (89.59% and 73.31%) for finer fractions (<100 ¦Ěm and 100 - 200 ¦Ěm, respectively). The best reducing power (36.15% and 34.27%) were also found in these finer powder fractions which improved by more than 2 times the value of mother powder (reducing power of 17.01%). These results suggest that grinding followed by sieve fractionation concentrates the majority of antioxidant phytochemicals in the EOs of the finer powder fractions of E.