Abstract:There is a growing interest of industry to replace synthetic chemicals by natural products with bioactive properties from plant origin. The aim of this study was to validate the therapeutic properties of Mentha pulegium L. by conducting a phytochemical study, to determine the chemical composition of its essential oils (EO) and evaluate its insecticidal activity against stored cereals pests. Leaves and flowers of M. pulegium L.were collected from three regions of the Moroccan Middle Atlas. Phytochemical tests on pennyroyal aerial parts revealed the presence of gallic tannins, flavonoids, alkaloids, sterols and triterpenes and saponins. The chemical composition of essential oils was analyzed by gas chromatography coupled with mass spectrometry. The main components were pulegone and piperitenone. The EO from Khénifra is dominated by pulegone (81.46%), and those from Azrou and M'rirt are rich both in pulegone (68.86 and 71.97%) and piperitenone (24.79% and 26.04%) respectively. Pennyroyal oil has showed an important fumigant effect against Sitophilus oryzae (L.) adults. This effect is influenced by the tested doses and exposure periods. The potential of this plant to be used to control stored product insects was discussed.

As part of valorisation of medicinal and aromatic plants from Timahdite, a region located in Moroccan Middle Atlas, we focused our study on an endemic species which belongstoAsteraceae family: Anacyclus pyrethrum L. This species, widely used by local people in traditional pharmacopeia, was chosen to conduct phytochemical studies and to assess the antioxidant activity of its roots, leaves and flowers extracts. Thus, the plant was harvested in May 2014. The selected organs (roots, leaves and flowers) of Anacyclus pyrethrum were sorted, cleaned and dried separately. Then, they were reduced into powder and stored away from light in a cool and dry place until use. Each organ was subjected to a phytochemical screening in order to qualitatively highlight its secondary metabolites. This qualitative analysis shows that roots are rich in alkaloids while the aerial parts (leaves and flowers) are rich in tannins and flavonoids. Extraction of total polyphenols was performed by maceration using methanol / water (70/30) as solvent. Yields were 2.30% for roots, 3.3% for leaves and 3.8% for flowers. Then, fractionation of hydro-methanol crude extract was carried out using successively three organic solvents of increasing polarity: chloroform, ethyl acetate and butanol. Quantitative analysis of total polyphenols conducted with Folin-Ciocalteu reagent showed that hydro-methanol crude extracts are richer in phenolic compounds than other fractions. Antioxidant activity of crude extracts determined through DPPH test was spectrophotometrically quantified and values of the half-maximal inhibitory concentrations (IC50) were graphically determined. These values are 77.62μggallic acid equivalent (GAE) / ml for flowers, 94.18μg / ml for leaves and 145.81μg / ml for roots, while 46.79μg / ml was found for ascorbic acid which was used as standard. Finally, a correlation was observed between total polyphenols content and antioxidant capacity determined by DPPH method: Aerial parts

The aim of this research is to profile the chemical composition of the essential oil (EO) extracted from the aerial parts of Origanum elongatum (O. elongatum) and to evaluate its antioxidant, antibacterial and insecticidal activities on Ceratitis capitata adults. Gas chromatography coupled with mass spectrometry (GC/MS) revealed a total of 27 constituents in EO of O. elongatum, which accounted for 99.08% of its constituents. Carvacrol (57.32%) was a main component, followed by p-cymene (14.70%) and γ-terpinene (9.84%). The antioxidant activity of O. elongatum EO was investigated using DPPH (1,1-diphenyl-2-picrylhydrazyl), FRAP (Ferric reducing antioxidant power), and TCA (the total antioxidant capacity) methods. This EO exhibited a remarkable antiradical and reducing power against DPPH (IC50 = 2.855 ± 0.018μL/mL), FRAP (EC0.5 = 0.124 ± 0.013µL/mL) and TCA (IC50 = 14.099 ± 0.389 mg AAE/g of the EO). The antibacterial tests in vitro, using the disc and dilution methods, were carried out on nine pathogenic bacteria isolated from the hospital patients, such as Enterococcus faecalis, Serratia fonticola, Staphylococcus aureus, Acinétobacter baumannii, Klebsiella oxytoca, Klebsiella pneumoniae sensible, E.coli sensible, E.coli resistante, and Enterobacter aerogenes. The EO demonstrated a considerable antibacterial activity with minimum inhibitory concentrations (MIC) from 2 to 8 µL/mL against all strains except Staphylococcus aureus (MIC = 32 µL/mL). Regarding the insecticidal activity, the fumigation test indicated a high efficacy (100% mortality), and a lethal dose of LD50  =  17 ± 0.53 μL/L air was found after 24 h of exposureTherefore, O. elongatum EO could be utilized as a natural antioxidant, antibiotic and biopesticides.

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Composition chimique d'Ammi visnaga L. (Lam.) marocaine et activité antibactérienne de son huile essentielle vis-à-vis de bactéries productrices et non productrices de beta-lactamases à spectre élargi Chemical composition of Moroccan Ammi visnaga L. (Lam.) and antibacterial activity of its essential oil against extended-spectrum beta-lactamase-producing and not producing bacteria