Etude de polyphénols des feuilles d’une endémique ibéro marocaine, Thymelaea lythroides.

RÉSUMÉ: Etude de polyphénols des feuilles d’une endémique ibéro marocaine, Thymelaea lythroides. Thymelaea lythroides (Thyméléacées) est une endémique ibéro marocaine, largement répandue dans la région du Gharb (forêt de Mamora). Elle fait partie de la panoplie des plantes médicinales et aromatiques du Maroc. En raison du manque d’informations phytochimiques sur l’espèce, des études antérieures ont eu pour objet une recherche de l’activité antifongique de ses extraits et un screening phytochimique. Ce dernier a permis de mettre en évidence la richesse de la plante en différents métabolites secondaires. Aussi, le présent travail se propose d’étudier les polyphénols des feuilles de Thymelaea lythroides et spécialement les aglycones flavoniques et les anthocyanidines. L’étude a démontré l’existence de différentes molécules appartenant à la classe des flavonols, dont le kaempférol, et la quercétine, en plus de deux acides phénols, identifiés comme l’acide caféique et l’acide genticique et deux anthocyanidines : la delphinidine et la cyanidine.Mots clés. Thymelaea lythroides, Thyméléacées, Mamora, polyphénols.ABSTRACT. Study of polyphenols of the leaves of an ibero moroccan endemic, Thymelaea lythroides. Thymelaea lythroides (Thymelaeacees) is an endemic of the region of the Gharb (forest of Mamora). It is part of the panoply of the medicinal and aromatic plants of Morocco. Because of the lack of phytochemical informations on the species, some previous studies had for object a research of the antifungal activity of its extracts and a phytochemical screening. This last permitted to put in evidence the wealth of the plant in different secondary compounds. Thus, the present work intends to study the polyphenols of the leaves of Thymelaea lythroides and specially the flavonics aglycones and the anthocyanidins. The survey demonstrated the existence of different molecules belonging to the class of the flavonols, whose identification revealed the kaempferol and quercetine. In addition to two acidic phenols, identified as the cofeique acid and the genticique acidic and two anthocyanidins, the delphinidine and the cyanidine.Key words. Thymelaea lythroides, Thymelaeacees, Mamora, polyphenols

Quantitative and Qualitative Analysis by HPLC of Major Peganum harmala Alkaloids at Different Stages of Development

The analysis of major Peganum harmala alkaloids (harmaline, harmine, harmol and harmalol) has shown that the content of these secondary metabolites depends on the plant development stage. The qualitative and quantitative profile of major alkaloids change significantly between stems, leaves and roots. The roots and seeds are the richest and most diversified organs in these metabolites. The concentration of the major alkaloids in all organs increases during the first three weeks and stabilizes at a constant level during vegetative growth phase and then decline at the beginning of flowering. On the scale of the whole plant, major alkaloids concentration of P. harmala varies with the developmental stage of the plant between 21.16 and 26.96 mg/g and harmine remains the most abundant molecule. Optimum exploitation of these natural products from the P. harmala plant is possible if the harvest of plant material occurs during the vegetative growth phase and at the appropriate stage for the richest organ. Keywords: Peganum harmala, Plant growth, Alkaloids, Harmine, Harmaline, Harmol, Harmalo

Effet De La Pollution Minière Sur La Phytochimie D’Argania spinosa (L.) Skeels

In this study, we propose new information about the argan tree in order to know the response of this tree to the difficult environmental conditions (pollution by the quarries). Since this tree is very interesting, not only by these ecological characteristics, but also by its economic potential and the value of its products. Thus, argan trees increase the secretion of phenolic compounds and saponins in order to adapt to the new conditions. Indeed, a screening of the phenolic compounds of the argan tree leaves of three stations, different in their dust attack levels due to quarries in the Abaynou region, was made. The results show that the Guelmim station, which is most affected by dust, has a significant difference in aglycones, total flavonoids and saponins compared to the Admine station which is further north and relatively far from any agglomeration and with the Agadir station considered intermediary

Isolement, Identification Et Activite Antifongique De Deux Sesquiterpenes D’asteriscus Graveolens Subsp. Odorus (Schousb.) Greuter

Two sesquiterpenes of Asteriscus graveolens subsp. odorus, have been extracted, separated, purified and identified by NMR and IR: the naupliolide and asteriscunolide 3c. The valuation of these compounds is part of the search for a preventive approach of integrated control to reduce significantly the use of pesticides and especially the fungicide ones. The results revealed a strong inhibitory effect on naupliolide against Botrytis cinerea, Penicillium digitatum and Penicillium expansum dice concentration of 200 ppm. The asteriscunolide 3c showed a remarkable effect against Botrytis cinerea from the concentration of 150 ppm

Antifungal and Antioxidant Activity of Asteriscus graveolens subsp. odorus Essential Oil

The essential oil of air-dried Asteriscus graveolens subsp. odorus, plant of southern Morocco, obtained by hydrodistillation were analysed by capillary gas chromatography-mass spectrometry (GC-MS). Twenty eight compound accounting 69.14% of the total oil was identified. The oxygenated sesquiterpenes 6-oxocyclonerolidol (30.72%) and epi-?-cadinol (14.50%) were the main constituents. The essential oil was tested for antifungal activity through mycelial growth inhibition tests in vitro against three agricultural pathogenic fungi: Penicillium digitatum, P. expansum and Botrytis cinerea. The essential oil at 125, 150, 200, 250, 500, 1000 and 2000 ppm was highly effective against mycelial growth of P. digitatum with 100% inhibition from the first day of incubation. Complete inhibition was also observed at 150, 200, 250, 500, 1000 and 2000 ppm concentrations of the essential oil from the first day of incubation for P. expansum. The doses 500, 1000 and 2000 ppm showed a percentage inhibition of 100% from day one for B. cinerea. Asteriscus graveolens subsp. odorus essential oil was also tested at different concentrations on Citrus fruits (Citrus reticulata Blanco cv. Nules) inoculated with P. digitatum (105 conidia ml-1, giving a fungistatic or fungicidal effect. In addition, the oil was subjected to screening for its possible antioxidant activity. For that, the in vitro assay based on the scavenging of the stable radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) was used. The Asteriscus graveolens subsp. odorus essential oil gave a value of CI50 0.2498 mg/ml. It inhibition percentage of free radical was slightly lower than that of BHT (the control compound) for all concentrations used. Our findings demonstrate that Asteriscus graveolens subsp. odorus essential oil possesses antioxidant and antifungal activities that might be a natural potential source of preservative and antifungal compounds used in food, in cosmetics and in pharmaceuticals products. Keywords: Medicinal plant, antifungal activity, antioxidant activity, citrus fruits, natural product

Enhancing rooting efficiency and nutrient uptake in Rosa damascena Mill. cuttings: insights into auxin and cutting type optimization

Auxin application plays a crucial role in successfully propagating and cultivating Rosa damascena Mill., a valuable plant species with cultural and economic significance. In this study, we aimed to investigate the effects of auxin dose and leaf presence on rooting success and nutrient uptake efficiency in Rosa damascena cuttings. Our results demonstrated that applying IBA significantly improved rooting success and nutrient absorption capacity, with a concentration of 1000 ppm being the most effective, resulting in a remarkable rooting percentage (48 ? 6%), increased root length (2.52 ? 0.25 cm) and improving leaf area (70.18 ? 5.10 cm2). The inclusion of leaves on cuttings has greatly magnified root success (90 ? 10%), leaf area (98.86 ? 17.86 cm2) and nutrient absorption efficiency, highlighting the vital role of leaves in early root development. Our findings provide valuable insights into the development of sustainable and productive cultivation methods for this significant plant species. Furthermore, our investigation emphasized the importance of optimizing auxin application, with leafy cuttings treated with 1000 ppm of auxin showing the most promising results regarding growth attributes, nutrient assimilation and survival rate

Chemical Composition and Anticandidal Effect of Three Thymus Species Essential Oils from Southwest of Morocco against the Emerging Nosocomial Fluconazole-Resistant Strains

The purpose of this present work is to study the essential oils composition of three endemic Thymus species from southwest of Morocco: Thymus satureioides Coss., Thymus pallidus Batt. and Thymus leptobotrys Murb., as well as their antifungal activity towards nineteen strains of emerging nosocomial Fluconazole-resistant Candida species. The chemical composition of the essential oils was determined by capillary gas chromatographic-mass spectrometry analysis. The results reveal qualitative and quantitative variation in composition of Thymus species. Seventy-three different compounds, 56 for T. satureioides accounting for 99.97% of the total essential oil, 52 for T. pallidus, accounting for 98.94% of the total essential oil, and 40 for T. leptobotrys accounting for 99.20%, were determined. The results obtained for the anticandidal disc-diffusion assay shows that the 19 strains of Candida species tested were inhibited by the Moroccan Thymus essential oils to a varying degree, with the diameters of the inhibition zone ranging from 49±1.00 to 85±1.15 mm. There were significant differences (p ? 0.05) in the antifungal activities of the essential oils on all species tested who showed larger inhibition zones than the positive control fluconazole and amphotericine B. Candida albicans showed a high sensitivity to essential oils of Thymus pallidus and Thymus leptobotrys compared with essential oil of Thymus satureioides and controls. While non- albicans Candida species showed less sensitivity to essential oils of Thymus pallidus and Thymus leptobotrys and are more sensitive to essential oils of Thymus satureioides than Candida albicans. Interestingly C. krusei, C. dubliniensis and C. glabrata were found to be resistant to conventional antifungal (fluconazole and amphotericine B), while our essential oils tested were able to inhibit the growth of Candida strains resistant to antifungal agents. The value of Minimal inhibitory concentration (MIC) and Minimal Fungicidal Concentration (MFC) of the Thymus essential oils studied ranges from 0.33 mg/mL to 0.91 mg/mL. All the essential oils possessed higher antifungal potential than classical fungicide. Keywords: Thymus species, essential oils, anticandidal activity, Nosocomial fluconazole-resistant strains