In this study, three samples of olive oil wastes: Olive Rinse Water (OR), Olive Mill Wastewater (OM) and Olive Pomace (OP), which were collected from an olive oil mill located at Fez-Morocco, were analyzed for their microbiota. A total of 81 isolates were obtained and constituted a microbial bank formed of 35 bacteria, 41 yeasts and 5 fungi. The microbial communities have been compared in term of metabolic potential by testing hydrolytic enzymes activities of lipase, protease, amylase, cellulase, pectinase and tannase on agar plate media. The results reveal that among the examined microorganisms, 68 isolates were able to produce at least one of the screened enzymes. The pectinase activity was the predominant one (39.51%), followed by cellulase activity (34.57%) and by lipase activity (27.16%). However, the amylase activity was observed only for 11.11% of the studied isolates, followed by protease activity (9.88%) and by tannase activity 6.17%. Thereby, considering the isolates ability to produce enzymes, they can be considered as potential candidates for industrial and biotechnological applications. Lipases

Many medicinal plants were studied for their phytochemical contents. Moringa oleifera is one of these plants. It is widely distributed in tropical and subtropical areas. It has an important medical uses with high nutritional value. This study, primarily aimed to carry out a preliminary phytochemical screening to detect the major classes of bioactive compounds presented in Moringa oleifera dry leaves. Many solvents (Methanol, ethanol, ethanol acetate and water) used to determine the best solvent can be used for extraction and to perform thin layer chromatography (TLC) profiling of all sequential extracts. TLC was carried out in silica gel plates using many mobile phase protocols, chloroform: methanol: ethanol (1:1:1), (2:2:0.5) and Chloroform: Glacial acetic acid: methanol (4:5:1) and use four mentioned solvents. Phytochemical screening of four extracts showed the presence of alkaloids, flavonoids, tannins, and phenols in all solvent extracts. However, the concentration of these compounds is more with ethanol and ethanol acetate extracts (+++). As well as thin layer chromatographic studies of the Moringa olifera leave extract (methanol, ethanol, ethanol acetate and water) constituted different colored phytochemical compounds with different Rf values. Methanol and ethyl acetate extracts were the best which show 4 bands with Rf less than 1 while with ethanol extract 5 bands with Rf less than 1 and with water extract no band appeared by using chloroform: methanol: ethanol (1:1:1). Furthermore with the other mobile phases detect fewer bands with different solvent extracts. The results obtained in the present study revealed that the concentration of the bioactive compounds of Moringa oleifera leaves extracts by using ethanol and ethyl acetate as a solvent is more than the other solvents. On the other hand, TLC showed 4 bands with better Rf by using methanol and ethyl acetate extract. Conclusion, the methanol and ethyl acetate extracts for Moringa oleifer leaves contain a higher content of bioactive compounds, which can be used for further researches on this plant.

A newly isolated strain, Proteus vulgaris OR34, from olive mill waste was found to secrete an alkaline extracellular lipase at 11 U• ml -1 when cultivated on an optimized liquid medium. This lipase was purified 94.64fold with a total yield of 9.11% and its maximal specific activity was shown to be 3232.58 and 1777.92 U•mg -1 when evaluated using the pH-stat technique at 55℃ and pH 9 and Tributyrin TC4 or olive oil as the substrate. The molecular mass of the pure OR34 lipase was estimated to be around 31 kDa, as revealed by SDS-PAGE and its substrate specificity was investigated using a variety of triglycerides. This assay revealed that OR34 lipase preferred short and medium chain fatty acids. In addition, this lipase was stable in the presence of high concentrations of bile salt (NaDC) and calcium ions appear not to be necessary for its activity. This lipase was inhibited by THL (Orlistat) which confirmed its identity as a serine enzyme. In addition, the immobilization of OR34 lipase by adsorption onto calcium carbonate increased its stability at higher temperatures and within a larger pH range. The immobilized lipase exhibited a high tolerance to organic solvents and retained 60% of its activity after 10 months of storage at 4℃. Finally, the OR34 lipase was applied in biodiesel synthesis via oleic acid mediated esterification of methanol when using hexane as solvent. The best conversion yield (67%) was obtained at 12 h and 40℃ using the immobilized enzyme and this enzyme could be reused for six cycles with the same efficiency.

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The increasing demand for baked products has given a boost to research on isolation and selection of novel yeast strains with improved leavening activity. Twelve sourdough samples were collected from several localities of the Fez region in Morocco. The pH and total titratable acidity (TTA) values of these samples varied from 3.03-4.63 and 14-17.5 ml of 0.1 N NaOH/10 g of sourdough, respectively, while yeast counts ranged from 5.3 6.77 Log CFU/g. Thirty-two yeast isolates were obtained and evaluated for their leavening ability. Out of all isolates, four yeasts molecularly identified as Saccharomyces cerevisiae (three strains) and Kluyveromyces marxianus (one strain) showed highest specific volumes of 4. 69, 4.55, 4.35 and 4.1 cm 3 /g, respectively. These strains were further assessed for their tolerance to high concentrations of salt, sugar, elevated temperatures, and low pH conditions. K. marxianus showed higher resistance than the S. cerevisiae. Thus, Moroccan sourdoughs harbor technologically relevant yeasts that could be used as potential starters for bread preparation.