Etude phytochimique et extraction de la vitamine C et des huiles essentielles de quelques plantes médicinales Algériennes - évaluation de l’activité antioxydante.

Abstract

The main purpose of this work is devoted to the extraction of essential oils of clove and bitter orange by the method of hydrodistillation, as well as the extraction of vitamin C from parsley and also the phytochemical study of the leaves of bitter orange tree, purification of a fraction from the dichloromethane phase of Artemisia herba alba (mugwort) and evaluation of the antioxidant activity of the oils obtained. The extracts obtained from the essential oils of clove and bitter orange as well as the ascorbic acid from the extraction of parsley are subjected to spectroscopic analyzes of the infrared with Fourier transform (FT-IR) to confirm the purity and the chemical composition of these extracts, essential oils are also analyzed by visible UV spectroscopy to assess their antioxidant activities. The results obtained show on the one hand the purity and richness of essential oils in chemical compounds such as eugenol (84.01%), eugenyl acetate (13.01%), major compounds of clove oil and limonene (0.40%) the majority compound of bitter orange essential oil, on the other hand the good separation of vitamin C in its natural state given the presence in the infrared spectrum of the characteristic bands of functions such as carbonyl (C=O), alkene (R2C=CR2), C-O (alcohol) and C-O (ether). The antioxidant activity of essential oils based on the DPPH free radical scavenging method to give satisfactory results, and shows that the antioxidant activity of clove essential oil (IC50 = 0.75 μg/mL) is stronger than that bitter orange (IC50 = 1.30 μg/mL) and control (IC50 = 5.00 μg/mL).