Composición química parcial y actividad antimicrobiana de extractos de Daucus critinus Desf

The chemical composition of fatty acids and the unsaponifiable fraction of the roots, leaves and stems from Daucus crinitus Desf. were, determined using gas chromatography (GC) and gas chromatography-Mass Spectrometry (GC-MS). The fatty acid fractions of different organs (leaves, stems and roots) were characterized by lauric acid (17.9, 17.5 and 18.1 % respectively) and other long chain fatty acids (until C22). Qualitative and quantitative differences were reported between the unsaponifiable fractions of different organs from D. crinitus. The unsaponifiable fractions of the leaves, roots and stem showed high amounts of aliphatic components (83.4%, 87.2% and 91.4%, respectively). The monoterpen, diterpen and sesquiterpen components were only present in small percentages. The antimicrobial properties of the D. critinus extracts were tested on four different microorganisms. These extracts were found to be active against Bacillus cereus, Staphylococcus aureus, Escherichia coli and Candida albicans.La composición química de los ácidos grasos y la fracción insaponificable de raíces, hojas, y tallos de Daucus crinitus Desf. fueron establecidas utilizando cromatografía de gases (GC) y cromatografía de gases-espectrometría de masas (GC-MS). La fracción de ácidos grasos de los diferentes órganos (hojas, tallos y raíces) se caracterizó por el ácido láurico (17.9, 17.5 y 18.1% respectivamente) y otros ácidos grasos de cadena larga (hasta C22). Diferencias cualitativas y cuantitativas se registraron entre las fracciones insaponificable de los diferentes órganos de D. crinitus. De hecho, las fracciones insaponificable de la raíz, de la hoja y del tallo mostraron cantidades altas de componentes alifáticos (83.4%, 87.2% y 91.4%, respectivamente). Los componentes monoterpénicos, diterpénicos y sesquiterpénicos solo estuvieron presentes en un pequeño porcentaje. Las propiedades antimicrobianas de los extractos de D. critinus fueron ensayadas en cuatro microorganismos diferentes. Estos extractos fueron activos contra Bacillus cereus, Staphylococcus aureus, Escherichia coli y Candida albicans

Caractérisation et variabilité des plantes à parfum aromatiques et médicinales de Corse et de l'Ouest algérien

Corsican and western Algerian flora is rich and well known. The Mediterranean basin is one of the Hotspot where biodiversity is concentrated. Like other regional red areas, these two regions are characterized by high richness endemism but also by strong anthropogenic threats growing rapidly. Essential oils are high value added products used in fields as diverse as perfumes, cosmetics, food processing or aromatherapy and pharmaceuticals. It is present generally in the form of complex mixture of several tens or even hundreds of terpene compounds in variable proportions. Production and characterization of essential oils, the quality control as well as the identification of a possible specificity requires the implementation of modern methods of preparation and analyzes. This work is based on the study of essential oils and volatile part of nine species and subspecies of Teucrium genius, growing in Corsica and western Algeria. The aim of this work is to contribute to improve knowledge of natural resources from plant biomass by providing objective scientific information. Three major axes have been developed: the main stand concerns the characterization of chemical compositions of essential oils; the other two stands are fully complementary: (i) a genetic axe that aims to establish the genetic sequence of Teucrium plants and examine the impact of the genetic information to production of secondary metabolites (ii) a microbiological demonstration based to antibacterial activity of essential oils studied.La richesse de la flore de Corse et de l'ouest algérien n‟est plus à démontrer. Le bassin méditerranéen est l'un des " points chauds " ou hotspot dans lesquels se trouve concentrée la biodiversité. A l'instar des autres zones rouges régionales, ces deux régions sont caractérisées par une richesse spécifique, un taux d‟endémisme élevé mais aussi par des menaces anthropiques fortes et en augmentation rapide. Les huiles essentielles sont des produits à forte valeur ajoutée utilisées dans des domaines aussi divers que la parfumerie, les cosmétiques, l‟agro-alimentaire ou encore l'aromathérapie et la pharmacie. Elles se présentent sous forme de mélanges complexes de plusieurs dizaines voire de plusieurs centaines de composés en général terpéniques présents dans des proportions variables. La production et la caractérisation des huiles essentielles, le contrôle de leur qualité tout autant que la mise en évidence d'une éventuelle spécificité nécessite la mise en oeuvre des méthodes de préparation et d'analyses les plus modernes. Ce travail de thèse repose sur l‟étude des huiles essentielles et des fractions volatiles de 9 espèces et sous-espèces du genre Teucrium, poussant en Corse et à l‟ouest algérien.Notre objectif est de contribuer à l‟amélioration des connaissances des ressources naturelles issues de la biomasse végétale en fournissant des informations scientifiques objectives. Ce travail de thèse a été l‟occasion de développer un travail méthodologique et appliqué totalement complémentaire. Ainsi trois grands volets ont été développés : Le principal volet est chimique, il concerne la caractérisation des compositions chimiques des huiles essentielles, les deux autres volets sont totalement complémentaires : (i) un volet génétique dont le but est d‟établir les séquences génétiques des plantes étudiées et examiner l‟impact du patrimoine génétique sur la production de métabolites secondaires (ii) un volet microbiologique basé sur la mise en évidence d‟activités antimicrobiennes des huiles essentielles étudiées

Chemical composition and biological activities of essential oil of Eryngium triquetrum from Western Algeria

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Chemical composition and antioxidant activity of hydrosol extracts obtained by liquid-liquid extraction (LLE) of Daucus muricatus L

International audienceChemical compositions and antioxidant activity of hydrosol extracts of roots, aerial parts, stems, leaves and flowers of Daucus muricatus L. obtained by liquid–liquid extraction (LLE) were reported for the first time. Gas chromatography (GC) and GC–mass spectrometry (GC–MS) analyses of hydrosol extracts showed only oxygenated compounds: thirty-six monoterpenes, fifteen sesquiterpenes, eight phenylpropanoids, eighteen non-terpenic compounds and one diterpene. Antioxidant activity was evaluated as free radical-scavenging capacity (RSC). RSC was assessed by measuring the scavenging activity of hydrosol extracts on 2,2-diphenyl-1-picrylhydrazil (DPPH). The best antioxidant activity was exhibited by flower and root hydrosol extracts at low concentrations (more than 100% at 20 μg/mL). Hydrosols produced by roots and aerial parts exhibited high contents of alcohol and phenolic compounds. However, a high result of ferric reducing antioxidant power for all hydrosol extracts tested was observed

Penicillium italicum control and antifungal activity of essential oil and hydrosol extract of Thymus capitatus L. against four fungal pathogens of Citrus sinensis L.

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Thiamine Deficiency as a Cause for Acute Circulatory Failure: An Overlooked Association in Western Countries

International audienceA 42 year-old patient presented with circulatory failure and lactic acidosis. Clinical features, later coupled with biological tests, led to the diagnosis of wet beriberi syndrome and scurvy. Echocardiography showed a pattern of thiamine deficiency with high cardiac output and low vascular resistance. The patient's condition and biological parameters immediately improved after treatment injections of thiamine. Wet BeriBeri is often overlooked in western countries and is a diagnosis that must be considered based on history, and clinical and echocardiographical findings

Control of fungal pathogens of Citrus sinensis L by essential oil and hydrosol extract of Thymus capitatus L.

International audienceEssential oil, hydrosol extract and hydrosol of Thymus capitatus L. from Algeria were tested for antifungal activity against four phytopathogenic fungi (Aspergillus niger, Aspergillus oryza, Penicillium italicum and Fusarium solani) causing the deterioration of Citrus sinensis fruits. Essential oil and hydrosol extract showed strong in vitro antifungal activity based on the inhibition zone and minimal inhibitory concentration values against the pathogens. Citrus sinensis fruits infected by Penicillium italicum were treated in vivo with essential oil, hydrosol extract and hydrosol. 0.2 μg/mL of Thymus hydrosol was needed for the absence of orange infection and causing 100 % mycelial growth inhibition. This activity can be correlated with chemical composition of extracts which are rich in carvacrol (more than 69 %). Therefore, the preventive and curative effects of T. capitatus essential oil and hydrosol could be exploited as an ideal alternative to synthetic fungicides for using in the treatment of many fungal phytopathogens causing severe destruction to oranges

Micropropagation and effect of phloroglucinol on rooting of Diospyros crassiflora Hiern

Open Access Journal; Published online: 05 Mar 2020The jet-black to streaked ebony wood produced by the African ebony (Diospyros crassiflora Hiern, Ebenaceae) is exploited in Central and West Africa. A conservation effort is currently underway in Cameroon to propagate the tree through seedlings and cuttings. However, the intermittent availability of its seeds and the long time required for rooting formation of cuttings are limiting its propagation. This study aims to develop a successful protocol for ebony micropropagation. In vitro culture of nodal segments from seedlings was performed in half-strength Murashige and Skoog (MS) medium supplemented with either zeatin (0.0, 2.3, 4.6, 9.1, 13.7, 18.2, 22.8, and 27.4 µm) or 6-benzylaminopurine (BAP) (0.0, 2.2, 4.4, 8.8, 13.3, 17.8, 22.2, and 26.6 µm). After 12 weeks, all media allowed shoot budbreak. Shoots displaying the greatest budbreak were observed with 22.8 µm zeatin and 22.2 µm BAP. The shoots were then transferred to a medium supplemented with indole-3-butyric acid (IBA) and phloroglucinol (PG) at different concentrations for root induction. Root induction was observed on the shoots initially induced in the medium with BAP, but not in those grown in the medium with zeatin. In half-strength MS supplemented with 396.5 µm PG plus 14.2 µm IBA, the formation of a single tap root was observed on 79% of shoots, with an average root length of 2.8 ± 0.18 cm. Rooted plants were successfully acclimatized to the greenhouse, with a 50% survival rate. This is the first report on Diospyros crassiflora micropropagation, which paves the way for rapid ebony multiplication to respond to needed conservation efforts

Chemical composition, antibacterial activity of a new essential oil chemotype of Algerian Artemisia arborescens L.

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