Plants of the Lamiaceae family are widely used for medicinal, cosmetic and culinary purposes. Phenolic compounds such as flavonoids and tannins are the main constituents of these plants; they have a proven multidirectional biological activity. Polyphenols have exceptional antioxidant potential, and they can intervene in the prevention of many health disorders. This work aims to study the composition and antioxidant power of phenolic compounds from crude extracts and fractions of Origanum elongatum leaves. This specie was subjected to phytochemical study through precipitation, turbidity and coloring reactions to highlight their secondary metabolites qualitative composition. Polyphenolic extraction was made by Soxhlet using two solvents: methanol 70%, ethanol 70%. Then, methanol’s crude was fractionated with solvents having escalating polarity; ethyl acetate, n-butanol. The polyphenols and flavonoids contents were spectrophotometrically estimated using Folin-Ciocalteau and Aluminum Trichloride methods. The antioxidant power of crude and fractionated extracts was evaluated by diphenyl-picryl-hydrazyl (DPPH●) and iron (FRAP) tests. The screening tests showed the existence of polyphenols, mucilages, sterols and triterpenes, oses and holosides. The highest yield of extraction is obtained by 70% methanol, with an average of 32.29%. Quantitative assays indicated that the hydroethanolic extract and the ethyl acetate fraction possessed high amount of polyphenols and flavonoids compared with other fractions and subsequently exhibited a marked scavenging activity on DPPH radical (IC50 = 0,085±0,002 and 0,112±0,003 mg/ml, respectively) and high reductive ability on ferric ion assay with IC50 = 0,181±0,004 mg/ml, 0,291±0,005 mg/ml, respectively.

<p>In this work, we are interested in both the study of the phenolic compounds and the evaluation of the antioxidant properties of the extracts of <em>Ammi visnaga L. </em>collected from the Middle Atlas in Morocco. Phytochemical screening was carried out to highlight the qualitative composition of the secondary metabolites contained in this plant. Also, the extraction of total polyphenols was carried out by maceration using hydromethanolic and hydroacetonic mixtures. Then, the fractionation of the crude extracts was conducted by liquid-liquid extraction using successively two organic solvents with different polarities: ethyl acetate and n-butanol. The polyphenols contents were spectrophotometrically estimated using the Folin-Ciocalteau method. It showed that the ethyl acetate fraction is more abundant in phenolic compounds than the other fractions. The qualitative analysis was performed by high-pressure liquid chromatography with U.V. and electrospray ionization coupled to mass spectrometry (HPLC/UV-ESI-MS), which confirmed the richness of this species in polyphenols and particularly in flavonoids, especially by the identification of kaempferol, rhamnetin, biochanin A, ammiol. These molecules belong to flavones, flavonols, and furochromones, which are also identified both in the form of genin and of heteroside.<strong> </strong>The antioxidant activity of the different fractions was evaluated by diphenyl-picryl-hydrazyl (DPPH^●). The IC₅₀ is equal to 12.87 μg / mL for the ethyl acetate fraction, against 8.8 μg / mL for ascorbic acid and 10.8 μg / mL for BHA which are used as reference compounds.</p>

Volatile and Non-Volatile Chemical Compounds and Biological Power of the genus Lavandula: Case of two Moroccan Lavenders Lavandula angustifolia Mill. (Cultivated Lavender) and Lavandula pedunculata (Mill.) Cav.

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<p>Among natural remedies, aromatic and medicinal plants constitute an essential source that deserves scientific attention. Thus, our study aims to promote the virtues of two aromatic and medicinal plants found in the wild in the region of Ouazzane (Morocco). The phytochemical tests of these species have shown the presence of flavonoids, gallic and catechic tannins, cyanidin, sterols and triterpenes. However, alkaloids, carotenoids, saponosides and reducing compounds were not detected. Then, extraction of total polyphenols from O<em>riganum compactum</em> and <em>Satureja calamintha nepeta</em> was conducted for 48 hours by maceration with a mixture of methanol/water (80/20) used as a solvent. Extractions yielded 35.2% crude extracts for <em>Origanum</em> <em>compactum</em> and 34.4% for <em>Satureja calamintha</em> <em>nepeta</em>. The fractionation of these crude methanol extracts was performed with three organic solvents of increasing polarity (chloroform, ethyl acetate then, n-butanol). Total phenol content of the extracts and fractions was assessed by the method of Folin-Ciocalteu. This revealed that the phenol-rich fractions were the crude extract for <em>Origanum compactum</em> and the butanol fraction for <em>Satureja calamintha</em> <em>nepeta</em>. Finally, the evaluation of the antioxidant power which was carried out using the method of trapping the free radical DPPH• and the reduction of iron by the method of FRAP. The DPPH• test showed a high antioxidant activity of the samples: 53.1 µg/ml of crude extract of <em>Origanum compactum</em> was needed to reduce 50% of DPPH•. The same IC₅₀ was obtained for ascorbic acid (standard antioxidant). For <em>Satureja calamintha nepeta,</em> the IC₅₀ was 67.5 µg/ml. On the other hand, the FRAP test revealed that the methanolic extract of <em>origanum compactum</em> has higher reducing power than that of n-buthanolic extract of <em>satureja calamintha nepeta. Still,</em> it remains relatively low compared to ascorbic acid. The high antioxidant activity of these two species could justify their use in traditional medicine for the treatment of many diseases.</p>