الملخص
Analysis of essential oil (EO) obtained from H. maroccana revealed that germanicol (17.8 %), β- pinene (14.6 %), α- guaiene (5.83 %), germacrene D (5.55 %), α- pinene (5.3 %) and δ- cadinene (5 %) were found to be the major components of this essential oil. Antimicrobial potential of H. maroccana oil in liquid and vapor phase against different bacterial strains (Staphylococcus aureus ATCC 6538, Bacillus subtilis ATCC 6633, Escherichia coli ATCC 8739, Salmonella abony NCTC 6017) and fungal strains (Alternaria sp., Pencillium expansum, Rhizopus stolonifer, Fusarium oxysporum f. sp. albedinisand Aspergillus brasiliensis ATCC 16404) was determined by the disc volatilization method and agar dilution method. The EO is considered moderately active against gram-negative strains (E. coli, S. abony), and those of gram-positive (S. aureus, B. subtilis). S. abony was the most sensitive bacteria, providing the lowest growth with an MIC equal to 0.156 mg mL-1. However, the mycelium growth was totally inhibited in the presence of the vapor generated by 0.5 μl mL-1 air for Alternaria sp.
الملخص
The diversity of thermophilic bacteria was investigated in four hot springs, three salt marshes and 12 desert sites in Morocco. Two hundred and forty (240) thermophilic bacteria were recovered, identified and characterized. All isolates were Gram positive, rod-shaped, spore forming and halotolerant. Based on BOXA1R-PCR and 16S rRNA gene sequencing, the recovered isolates were dominated by the genus Bacillus (97.5%) represented by B. licheniformis (119), B. aerius (44), B. sonorensis (33), B. subtilis (subsp. spizizenii (2) and subsp. inaquosurum (6)), B. amyloliquefaciens (subsp. amyloliquefaciens (4) and subsp. plantarum (4)), B. tequilensis (3), B. pumilus (3) and Bacillus sp. (19). Only six isolates (2.5%) belonged to the genus Aeribacillus represented by A. pallidus (4) and Aeribacillus sp. (2). In this study, B. aerius and B. tequilensis are described for the first time as thermophilic bacteria. Moreover, 71.25%, 50.41% and 5.41% of total strains exhibited high amylolytic, proteolytic or cellulolytic activity respectively.
الموضوعات
Bacillaceae/classification , Bacillaceae/isolation & purification , Gram-Positive Rods/classification , Gram-Positive Rods/isolation & purification , Hot Springs/microbiology , Soil Microbiology , Water Microbiology , Biodiversity , Bacillaceae/genetics , Bacillaceae/radiation effects , Cluster Analysis , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Gram-Positive Rods/genetics , Gram-Positive Rods/radiation effects , Molecular Sequence Data , Morocco , Phylogeny , /genetics , Sequence Analysis, DNA , Spores, Bacterial/cytologyالملخص
Aims: Through the National Botanical Research Institute's phosphate growth medium (NBRIP) and 16S rDNA sequence analysis were used to isolate and identify the bacterial groups that actively solubilized phosphates in vitro from rhizosphere soil for three cultvited leguminous in agricultural soils from Meknes region. Study Design: Rhizosphere soil samples for three cultivated legumes in different sites from Meknes region were collected for the study. Place and Duration of Study: Department of biology (Soil & Environment Microbiology Unit) Faculty of Sciences, Moulay Ismail University, Meknes, Morocco; between January and July 2014. Methodology: Out of several hundred colonies that grew on NBRIP medium eight best isolates were selected based on the solubilization of insoluble phosphates in solid medium with solubilizing index (SI) and Phosphate concentration solubilized in liquid medium; The bacterial isolates were identified based on their phenotypic and 16S rDNA genes sequencing. Results: P solubilization index of these isolates ranged from 2.51 to 6. Drop in pH of the medium ranged from 6.8 to 3.2 with the continuous growth of these isolates for seven days. P-solubilized ranged from 50.95 to 113.11 mg L-1. They were clustered under the genera Enterobacter, Pantoea, Rhizobium, Klebsiella, Rahnella, Bacillus and Burkholderia. Conclusion: This research extends the knowledge on Phosphate solubilizing bacteria in the rhizosphere of some cultivated legumes from Meknes region and development of environmentally friendly bio-Phosphate fertilizers.
الملخص
Aims: The objectives were to isolate and characterize phenotypically and genotypically the rhizobial strains from the soils belonging to the Meknes-Tafilalet region in order to select strains that are able to nodulate Bituminaria bituminosa. Study Design: An experimental study. Place and Duration of Study: Department of biology (Soil & Environment Microbiology Unit) Faculty of Sciences, Moulay Ismail University and Technical Support Unit for Scientific Research, CNRST in Rabat; between January and August 2010. Methodology: Samples from 23 different sites belonging to the Meknes-Tafilalet region were collected in order to select rhizobial strains that are able to nodulate Bituminaria bituminosa. The morphological, cultural and phenotypic parameters of isolated strains were studied. The phenotypic characteristics include colony morphology, growth speed, tolerances to temperature, salt and pH. To assess the genotypic diversity among the isolates, molecular characteristics based on 16S rDNA gene sequencing were performed. Results: The majority of the isolated strains showed fast-growing capacity (75%). Most strains tolerate neutral to alkaline pH, however some strains (18%) showed weak growth capacity at pH 4. All isolates were tolerant to high salt stress ([NaCl] = 3%). The genotypic characterization based on16S rDNA gene sequencing of the twelve strains showed a high diversity between the isolates. Conclusion: Taken together, our results highlight the important biodiversity of the isolated rhizobial strains and open opportunities for the development of new bio-fertilizer.