The essential oil from aerial part of Marrubium deserti De Noé (Lamiaceae), obtained by hydrodistillation was analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS), and evaluated for in vitro antimicrobial activity. The antioxidant activity was determined using three in vitro assays: scavenging effect on DPPH, the ABTS test and the phosphomolybdenum method. Thirty-seven compounds were identified in the oil, with germacrene D as the major component (45.7%). This oil was characterized by an important hydrocarbon fraction (78.1%) and by the predominance of sesquiterpenes (67.4%). M. deserti essential oil had no activity on the tested microorganisms (Staphylococcus aureus ATCC 25923, Echerichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Candida albicans and Aspergillus flavus). However the oil presented an antioxidant activity.

No abstract

Marrubium vulgare, plant species belonging to Marrubium genus, is widespread in the Mediterranean areas, introduced elsewhere and also cultivated in many countries. Its oil is recognized to possess a considerable biological activities with varied chemical composition. This paper aims to overview the chemical composition and biological activities of M. vulgare essential oil's considered as a medicinal plant, widely used in folk medicine overall the world. In essential oils of M. vulgare, germacrene D, β-caryophyllene, β-bisabolene, bicyclogermacrene and carvacrol are generally considered as either mains or minor constituents and each species presents its own composition. Sesquiterpenoids were the dominant fraction while monoterpenoids were present in appreciable or in trace amount. Oxygenated fractions dominated in monoterpenes however, hydrocarbon fraction overpowered in sesquiterpenes. These oils are biologically active, they exhibit an antioxidant and antimicrobial activities and other activities. Due to the variability of composition of essential oil, further studies are necessary, particularly regarding their chemical's which may cause an important change in the biological activities of oils and probably defined different chemotype.

No abstract

Exopolysaccharides synthesized by lactic acid bacteria play a major role in the manufacturing of fermented dairy products as thickening agents. Exploration of the biodiversity of wild lactic acid bacteria from natural environments is currently the most suitable approach to search for the desired exopolysaccharide-phenotype. A total of 82 thermophilic lactic acid bacteria strains were isolated from Algerian raw camel milk. The isolation of strains was carried on modified Chalmers agar medium, under semi anaerobic conditions at 42°C. Bacterial isolates were phenotypically characterized and grouped into four genera: Lactobacillus (31.7%), Enterococcus (30.5%), Streptococcus (24.4%) and Pediococcus (13.4%). Based on the mucous type of the colonies, thirty EPS-positive strains were selected to be screened for their ability to produce exopolysaccharides. The production of polymers was carried out on Man, Rogosa and Sharpe (MRS) broth, supplemented with lactose and glucose as carbon sources. Yields quantification of soluble exopolysaccharides using a colorimetric method, showed that the selected strains produce yields ranging between 160 and 740 mg/l for Lactobacillus strains, between 126 and 319 mg/l for Streptococcus strains, between 70 and 242 mg/l for Enterococcus strains and between 132 and 134 mg/l for Pediococcus strains. This suggests that some strains have potential to be used as new culture starters for this and possibility other dairy products.

No abstract

Le cheptel ovin algérien reste méconnu, malgré son intérêt économique et les qualités très précieuses des races locales qui montrent des adaptations exceptionnelles dans des conditions environnementales extrêmes. La variabilité phénotypique de la Rembi, race algérienne menacée, a été étudiée au moyen d’une analyse discriminante multivariée. L’échantillonnage a pris en considération la diversité des environnements de production présents dans le pays selon les recommandations de la FAO. Au total 722 femelles et 60 mâles ont été phénotypés sur une grande zone incluant le berceau de la race, en utilisant 21 variables quantitatives et 12 variables qualitatives. Les résultats montrent une forte homogénéité phénotypique qui suggère une homogénéité intraraciale au niveau génétique, à confirmer par des analyses moléculaires. En effet, aucune structuration phénotypique n’a été mise en évidence, que ce soit en considérant le statut de la ferme (privée/étatique), la zone climatique (aride/semi-aride/subhumide), la mobilité du troupeau (sédentaire/semi-sédentaire/transhumant) ou encore la variété. Seule la considération du facteur région a permis la mise en évidence de sous-groupes au sein de la race. Les échanges commerciaux, organisés autour de marchés principaux, favorisent les flux d’individus à l’intérieur des différentes régions et semblent responsables d’un modèle phénotypique unique. Ces résultats permettent pour la première fois de caractériser finement la Rembi. Les indices morphologiques la situent notamment parmi les races à viande. Cette étude est la première étape vers la mise en place de programmes de conservation de cette race très menacée par des croisements avec la Ouled-Djellal, la race algérienne dominante.

No abstract