Le volcanisme permien des Vosges du Nord : un temoin d'une evolution dans le cycle orogenique varisque de l'Europe occidentale

SIGLECNRS T 63624 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Integrated Analysis by GC/MS and ¹³C NMR of Moroccan <i>Cladanthus mixtus</i> Essential Oil; Identification of Uncommon Epoxyfarnesanes

Cladanthus mixtus (L.) Chevall., Asteraceae, also known as Moroccan chamomile, is a spontaneous, annual plant growing wild in North-Western Morocco. Economically, the essential oil of C. mixtus is of high interest, Morocco being the only supplier on the international market. Two essential oil samples (EO) were isolated from aerial parts of Cladanthus mixtus (L.) Chevall., and analyzed by a combination of chromatographic and spectroscopic techniques (gas chromatography (GC) in combination with retention indices (RI), gas chromatography-mass spectrometry (GC/MS), and 13C NMR spectroscopy). Computer matching against the in-house 13C NMR library allowed the identification of the eight components at appreciable contents, namely 3,6,6,9-bis-epoxy-farnesa-1,7(14),10-triene, and its 3-epi, 9-epi, and 3,9-diepi epimers, and 6,9-epoxy-farnesa-1,7(14),10-trien-3-ol and its 3-epi, 6-epi, and 3,6-diepi epimers. Our results confirm the tremendous chemical variability of Moroccan C. mixtus essential oil and the usefulness of 13C NMR analysis, in combination with GC(RI), for the identification of uncommon oxygenated sesquiterpenes that induce an original composition

Effet du site sur la germination des graines de deux espèces de Cladanthus au Maroc

Seed germination of two species of the genus Cladanthus: Cladanthus mixtus (annual plant) and Cladanthus scariosus (perennial plant) was studied. The aim of this work was to determine germination differences at the inter-site level for both species (7 sites for each species) and at the intra-site level (Three accessions for each site) for C. mixtus. The germination test was carried out in a laboratory room at an average temperature of 18 °C. Six parameters were determined: Final germination percentage (FGP), mean germination time (MGT), coefficient of the variation of germination time (CVt), germination index (GI), coefficient of velocity of germination (CVG), and median germination time (T50). The average germination percentages were 95.2 and 83.8%, respectively for C. mixtus and C. scariosus. Germination time and speed were highly variable at the inter-site level for both species. The provenance of seeds significantly affects the germination capacity. Germination was better in the sites: Larache, Sidi Chafi and Sidi Taibi for C. mixtus and in Ijoukak 1 and Ijoukak 2 for C. scariosus. The mean values of C. mixtus and C. scariosus are respectively: 92.2-98.7% and 70.0-93.0%. The accession effect in C. mixtus was significant for the final germination percent at four sites (Larache, Boghadi, Harcha and Ain El Aouda). For other parameters (MGT, GI and CVG), significant differences were observed mainly in Tiddas and Boghadi. This inter-site variability must be considered for the ex-situ conservation and domestication initiation of C. mixtus and C. scariosus.La germination des graines de deux espèces du genre Cladanthus : Cladanthus mixtus (plante annuelle) et Cladanthus scariosus (plante pérenne) a été étudié. L’objectif de ce travail est de déterminer les différences de germination au niveau inter-sites pour les deux espèces (7 sites par espèce) et au niveau intra-site (effet accession) pour C. mixtus. Le test de germination est réalisé au laboratoire à une température moyenne de 18°C. Les paramètres déterminés sont : pourcentage de germination final (FGP), temps de germination moyen (MGT), coefficient de variation du temps de germination (CVt), indice de germination (GI), coefficient de vitesse de germination (CVG) et temps médian de germination (T50). Les pourcentages moyens de germination sont de 95,2 et 83,8% respectivement chez C. mixtus et C. scariosus. Le temps et la vitesse de germination ont montré des différences significatives au niveau inter-sites pour les deux espèces. La provenance des graines affecte significativement la capacité de germination. La germination était meilleure dans les sites : Larache, Sidi Chafi et Sidi Taibi pour C. mixtus et Ijoukak 1 et Ijoukak 2 pour C. scariosus. Les valeurs moyennes de C. mixtus et C. scariosus sont respectivement : 92,2-98,7 % et 70,0-93,0 %. L'effet accession chez C. mixtus s'est avéré significatif pour le pourcentage de germination dans quatre sites (Larache, Boghadi, Harcha and Ain El Aouda). Pour d’autres paramètres (MGT, GI et CVG), des différences significatives ont été observées principalement à Tiddas et Boghadi. Cette variabilité inter-sites doit être prise en considération pour la conservation ex-situ et l'initiation de la domestication de C. mixtus et C. scariosus

Phytochemical Components, Antioxidant Properties, Antimicrobial Effects, and Insecticidal Prospects Against the Black Bean Aphid ( Aphis fabae Scop.) of Olea europaea L. Leaves Extracts from Morocco

The escalating phenomenon of bacterial resistance to antibiotics over time, coupled with the conse-quential detrimental effects of oxidative stress on cellular aging, and the usage of pesticides with vary-ing degrees of toxicity, thereby impacting both human health and the environment, represents a pressing global concern. Consequently, researchers are compelled to identify novel biomolecules de-rived from plants and their derivatives that possess antibacterial, antioxidant, and insecticidal proper-ties. The olive tree (Olea europaea L.), a fruit-bearing tree within the Oleaceae family, characterized by its olives, has been cultivated for millennia, particularly in Mediterranean regions, with its leaves being primarily employed for their multifarious therapeutic attributes. In this investigation, extracts were procured from olive leaves through employment of the Soxhlet apparatus, followed by the quantifica-tion of total polyphenols and flavonoids. The assessment of the antioxidant potential of these extracts was conducted using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The antibacterial efficacy was evaluated via the disk diffusion method against six pathogenic bacterial strains, namely Staphylococcus aureus, Escherichia coli, Acinetobacter baumannii, Salmonella sp, Klebsiella pneumoniae, and Pseudo-monas aeruginosa. Additionally, the in vitro aphicide activity of Olea europaea L. extracts were investi-gated at concentrations of 0.5%, 1%, 1.5%, 2%, and 2.5% against the black bean aphid, Aphis fabae Scop. The findings of this study suggest that olive leaf extracts exhibit robust antioxidant properties and dis-play modest antibacterial activity against pathogenic agents. Hence, these extracts are strongly en-dorsed for their potential role as eco-friendly antioxidants, and owing to their modest yet efficient in-sect-repelling attributes, they can be utilized as a sustainable, low-impact insecticide in the ecological engineering approach to controlling black aphids in bean crops. Therefore, the utilization of olive tree-derived extracts is encouraged

Low incidence of SARS-CoV-2, risk factors of mortality and the course of illness in the French national cohort of dialysis patients

International audienceThe aim of this study was to estimate the incidence of COVID-19 disease in the French national population of dialysis patients, their course of illness and to identify the risk factors associated with mortality. Our study included all patients on dialysis recorded in the French REIN Registry in April 2020. Clinical characteristics at last follow-up and the evolution of COVID-19 illness severity over time were recorded for diagnosed cases (either suspicious clinical symptoms, characteristic signs on the chest scan or a positive reverse transcription polymerase chain reaction) for SARS-CoV-2. A total of 1,621 infected patients were reported on the REIN registry from March 16th, 2020 to May 4th, 2020. Of these, 344 died. The prevalence of COVID-19 patients varied from less than 1% to 10% between regions. The probability of being a case was higher in males, patients with diabetes, those in need of assistance for transfer or treated at a self-care unit. Dialysis at home was associated with a lower probability of being infected as was being a smoker, a former smoker, having an active malignancy, or peripheral vascular disease. Mortality in diagnosed cases (21%) was associated with the same causes as in the general population. Higher age, hypoalbuminemia and the presence of an ischemic heart disease were statistically independently associated with a higher risk of death. Being treated at a selfcare unit was associated with a lower risk. Thus, our study showed a relatively low frequency of COVID-19 among dialysis patients contrary to what might have been assumed