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Kadri Z.,French National Center for Scientific Research | Kadri Z.,Laboratoire Of Biotechnologie Microbienne | Amar M.,French National Center for Scientific Research | Ouadghiri M.,French National Center for Scientific Research | And 4 more authors.
International Journal of Systematic and Evolutionary Microbiology | Year: 2014

Two catalase- and oxidase-negative Streptococcus-like strains, LMG 27682Tand LMG 27684T, were isolated from raw camel milk in Morocco. Comparative 16S rRNA gene sequencing assigned these bacteria to the genus Streptococcus with Streptococcus rupicaprae 2777-2-07T as their closest phylogenetic neighbour (95.9 % and 95.7 % similarity, respectively). 16S rRNA gene sequence similarity between the two strains was 96.7 %. Although strains LMG 27682Tand LMG 27684T shared a DNA-DNA hybridization value that corresponded to the threshold level for species delineation (68 %), the two strains could be distinguished by multiple biochemical tests, sequence analysis of the phenylalanyl-tRNA synthase (pheS), RNA polymerase (rpoA) and ATP synthase (atpA) genes and by their MALDI-TOF MS profiles. On the basis of these considerable phenotypic and genotypic differences, we propose to classify both strains as novel species of the genus Streptococcus, for which the names Streptococcus moroccensis sp. nov. (type strain, LMG 27682T = CCMM B831T) and Streptococcus rifensis sp. nov. (type strain, LMG 27684T = CCMM B833T) are proposed. © 2014 IUMS.

Hamadi F.,University Ibn Zohr | Hamadi F.,Sultan Moulay Slimane University | Asserne F.,Sultan Moulay Slimane University | Elabed S.,University Sidi Mohammed Ben Abdellah | And 5 more authors.
Food Control | Year: 2014

Staphylococcus aureus has the ability to adhere and to form biofilm on inert surface such as stainless steel commonly used in food industry. The biofilm formed on the surface of milk processing equipments could be a source of dairy products contamination. This contamination causes a food poisoning. In this paper the S.aureus adhesion on stainless steel treated by three types of milk (ultrahigh-temperature (UHT)-treated milk; UHT skimmed milk, UHT semi-skimmed milk) was investigated.Stainless steel was exposed to three types of milk with a different amount of fat component. Contact angles measurements were used to determine the surface physicochemical properties of substratum treated with the three milk products. The hydrophobicity and electron acceptor properties of stainless steel seem to be decreasing with the amount of fat component present in milk but its electron donor property increase with this component. The ability of S. aureus to adhere to stainless steel treated and untreated with milk was also examined. Treatment with the three types of milk reduces bacterial attachment. On treated substratum, the adhesion extent was affected by the type of milk and consequently by the amount of fat component. The lower and the higher adhesion were obtained when the steel was treated by the UHT semi-skimmed milk and UHT skimmed milk respectively. The correlation between physicochemical properties and S.aureus adhesion show that this latter was controlled by hydrophobicity and electron donor properties.The findings of this work can contribute to develop strategies for prevent S.aureus adhesion on stainless steel and biofilm formation. Also they could be taken into account in cleaning and disinfection procedures. © 2013 Elsevier Ltd.

Kadri Z.,French National Center for Scientific Research | Kadri Z.,Laboratoire Of Biotechnologie Microbienne | Vandamme P.,Ghent University | Ouadghiri M.,French National Center for Scientific Research | And 6 more authors.
Antonie van Leeuwenhoek, International Journal of General and Molecular Microbiology | Year: 2015

Biochemical and molecular genetic studies were performed on two unidentified Gram-stain positive, catalase and oxidase negative, non-hemolytic Streptococcus-like organisms recovered from raw camel milk in Morocco. Phenotypic characterization and comparative 16S rRNA gene sequencing demonstrated that the two strains were highly different from each other and that they did not correspond to any recognized species of the genus Streptococcus. Phylogenetic analysis based on 16S rRNA gene sequences showed the unidentified organisms each formed a hitherto unknown sub-line within the genus Streptococcus, displaying a close affinity with Streptococcus moroccensis, Streptococcus minor and Streptococcus ovis. DNA G+C content determination, MALDI-TOF mass spectrometry and biochemical tests demonstrated the bacterial isolates represent two novel species. Based on the phenotypic distinctiveness of the new bacteria and molecular genetic evidence, it is proposed to classify the two strains as Streptococcus tangierensis sp. nov., with CCMM B832T (=LMG 27683T) as the type strain, and Streptococcus cameli sp. nov., with CCMM B834T (=LMG 27685T) as the type strain. © 2014, Springer International Publishing Switzerland.

Bourkhiss M.,Moulay Ismai University | Hnach M.,Moulay Ismai University | Lakhlifi T.,Moulay Ismai University | Bouachrine M.,University Sidi Mohammed Ben Abdellah | And 5 more authors.
Phytotherapie | Year: 2012

With a view to contributing to the evaluation of Moroccan flora through the identification of new potentially interesting substances at a biological and therapeutic level, we have undertaken a study of the essential oils in the sawdust of the Tetraclinis articulata (Vahl) Masters originating from the Khemisset region (Morocco). The study of the sawdust's essential oil, completed by CPG and CPG/SM, identified 22 components, the main five being: α-acorenol (20.9%), cedrol (17.9%), totarol (8.8%), α-cedrene (8.7%) and β-acorenol (7.4%). This essential oil was fractionated on an open silica column using an eluent of increasing polarity. Five fractions were collected in this way. The fraction (FH) eluted with the pentane comprised sesquiterpene hydrocarbons whereas the four oxygenated fractions (FO 1 to FO 4) eluted with a diethyl oxide/pentane mix of increasing polarity were dominated by a diterpenoid phenol and two sesquiterpene alcohols respectively: totarol in the FO 1 fraction (42.4%), α-acorenol in the FO 2 (34.9%) and FO 3 (54.0%) fractions, and cedrol in the FO 4 fraction (58.2%). The sawdust's oil and its chromato-graphic fractions were tested in vitro against four bacterium: Escherichia coli, Bacillus subtilis, Staphylococcus aureus and Micrococcus luteus, and three funghi: Penicillium parasiticus, Aspergillus niger and Trametes pini. The unfractionated essential oil and oxygenated fractions, particularly FO 1, comprising mainly of totarol, were the most active. Therefore, the FO 1 fraction would be recommended for optimising the anti microbial activity of the Tetraclinis articulata's essential oils. © Springer-Verlag France 2012.

Soumya E.A.,Laboratoire Of Biotechnologie Microbienne | Saad I.K.,Laboratoire Of Biotechnologie Microbienne | Saad I.K.,University Sidi Mohammed Ben Abdellah | Hassan L.,Laboratoire Of Valorisation Et Of Securite Des Produits Agroalimentaires | And 3 more authors.
African Journal of Microbiology Research | Year: 2011

Pseudomonas aeruginosa has a high propensity to develop biofilms that are resistant to exogenous deleterious agents. The aim of this study was to investigate whether carvacrol and thymol can interfere with adherence phenomena as well as acting on biofilm formation. Tests of P. aeruginosa strains showed that carvacrol and thymol interferes with the starting phases of adherence as well as with P. aeruginosa biofilms. Carvacrol and thymol (2MIC) inhibition was 97±8.5 and 89±6.3% for P. aeruginosa (ATCC 27853) and 72±4.6 and 69±6.8% for P. aeruginosa (CIP A22) adherence respectively. Carvacrol (2MIC) inhibition exceeds 90% for P. aeruginosa (ATCC 27853) and P. aeruginosa (IL5) biofilm. Thymol (2MIC) inhibition is 86±2.1, 54±5.9 and 70±4.3% for P. aeruginosa (ATCC 27853) P. aeruginosa (CIP A22), P. aeruginosa (IL5), respectively. © 2011 Academic Journals.

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