الخلاصة:
This study is carried out with the aim of verifying the specificity of a plant with medicinal interest: Hammada scoparia (Pomel) Iljinor Saligne à balai in two different sites Metlili and Berriane of the region of Ghardaia in the northern Algerian Sahara, from the point of view biochemical and biological in particular the antioxidant activity of the crude aqueous extracts obtained by cold maceration of the aerial and root parts dried in the open air or in an oven (45° C). To do this, tests for the presence or absence of the main compounds of the secondary metabolism of the plant are carried out. Dry extracts by aqueous maceration are obtained and their yields are then determined by following the two drying methods concerned. The total polyphenol contents in its crude extracts are then evaluated and their antioxidant potential against the free radical DPPH is finally determined.
From most of the results obtained, the first method of drying, in the open air, seems to be better than drying in the oven for most of the results obtained. In other words, drying in the open air at room temperature made it possible to obtain a yield of crude extract greater than 52.1% of the powder of the aerial part of the plant species Hammada scoparia de Berriane. In general, the crude extracts from the aerial part of our plant species are found to be the richest in polyphenolic compounds for both drying methods with a maximum content of around 257.48 mg GAE/ g DPM.
Antioxidant potency tests show that crude extracts isolated from the species from the two relevant sites in the Ghardaia region are very active and generally exhibit superior antioxidant activities. In general, the crude aqueous extracts from the underground part of the Metlili species exhibit the strongest inhibitory power of the DPPH radical with more or less low IC50 values not exceeding 2.6 mg / mL. These inhibitory powers of the crude extracts obtained are found to be lower compared to that of trolox which has been shown to be very potent and to have a very high capacity in reducing the free radical DPPH.
To end, the Hammada scoparia species from the Metlili region is much more better than that of Berriane from the point of view of biochemical richness in polyphenolic compounds and antioxidant activity, especially in its root part.