ABSTRACT: In the first part of this study, we were proceeded tothe evaluation of the antibacteria... more ABSTRACT: In the first part of this study, we were proceeded tothe evaluation of the antibacterial effect of the organicextracts from the leaves of three plant species of Menthaagainst six pathogenic bacterial strains including Gram (-)bacteria and Gram (+) bacteria. The methods of diffusionin solid and micro-dilution method in liquid medium wereused for antibacterial testing. The results showed that nonpolarextracts are much more active then polar extracts. TheGram (+) bacteria showed more sensitive than the Gram (-)bacteria. S. aureus was shown to be the most sensitive of allbacteria testing in this study, it was sensitive against allextracts include that aqueous. All aqueous extracts haveno antibacterial activity with the highest concentration used(12 mg/ml) against the five other strains. In the second part, non-polar extracts were tested for their anti-biofilm effect against biofilms formed by S. aureus and E. coli in 48 hours. All extracts showed a spectacular antibiofilm effect with elimination of all the biofilms formed after 30 min of treatment.
The present study aims to assess the effect of phosphate solubilizing bacteria (PSB) in interacti... more The present study aims to assess the effect of phosphate solubilizing bacteria (PSB) in interaction with native arbuscular mycorrhizal fungi (AMF) and rhizobia on peanut growth cultivated in the Northwest of Morocco. To perform this aim, seeds were inoculated with 5 PSB strains: PP22, GP70, GR1, PR29, and GR70, and then grown in unsterilized soil collected from peanut fields. Plant harvesting was made after 8 weeks of growth under chamber conditions. The results demonstrated that PSB treatments showed positive effect on mycorrhizal colonization, nodulation and plant growth parameters. The best results were found with Pseudomonas strains, GP70, PP22 and GR1. This study indicates the great potential of some PSB to improve yield and nutrient uptake of peanut plants in the presence of native rhizobia and AMF. They could serve as biofertilizers, minimizing chemical fertilization that is currently used to obtain high yields for peanut agriculture. Keywords: AMF, growth, peanut, PSB, rhizobia
This work exposes the analysis and the modeling of the kinetics of desiccation of strawberries du... more This work exposes the analysis and the modeling of the kinetics of desiccation of strawberries during the freeze-drying process. A lyophilisator Virtis 35L Gardiner was used. Freeze-drying was carried out at various temperatures. The impact study of the various parameters of freeze-drying process of Moroccan strawberries showed that the temperature has an important incidence on the reduction process duration, thus minimizing the cost of the process while preserving the quality of the dry fruit and opening the field with the application of this technology to the treatment of new food products.
The development of a biological alternative to chemical fertilizers is of great importance for th... more The development of a biological alternative to chemical fertilizers is of great importance for the improvement of agriculture as well as protection of the environment. Achieving this goal, 305 bacteria were isolated from thé rhizosphere of rice fields in Northwestern Morocco, of which 136 rhizobacteria were tricalcique phosphate solubilizers. Based on diameter of solubilization halos, the 17 best phosphate solubilizers, Gram-negative, were selected. Six isolates were able to produce the indole acetic acid, while 3 bacteria were positive for hydrogel cyanide synthesis. Nine bacteria were chosen for more activities. Except the isolate P66, all bacteria were siderophores producers. No bacteria fixed nitrogen, while ACC deaminase was detected in three bacteria, E34, E68 and E85.The solubilization of other inorganic forms of insoluble phosphate was quantitatively evaluated and all isolates couldn t dissolve both forms FePO4 and AlPO4, while 7 bacteria were found to be Ca5HO13P3 and CaHPO...
Ce travail présente l'étude de la solubilisation de phosphate tricalcique par des Rhizobium i... more Ce travail présente l'étude de la solubilisation de phosphate tricalcique par des Rhizobium isolés des nodules de trois légumineuses (Hydesarum coronarium, Vicia sativa, et Lupinus angustifolius), et tester leur effet sur la germination des semences du triticale, variété Momtaz. Dans un premier temps, les 53 isolats obtenus ont été testés sur milieu PVK solide renfermant 0,5% de phosphate tricalcique (PTC), afin de garder ceux ayant l'activité solubilisatrice de PTC. Ainsi, six isolats (H2-7, H2-10, H3-5, L1, L2 et L5) ont donné des halos de solubilisation de diamètre oscillant entre 0,3 cm et 0,6 cm. Par la suite, ces isolats ont été soumis au test quantitatif dans le milieu PVK liquide en mesurant le P solubilisé et le pH. Les résultats obtenus sont compris entre 9,62 mg/L et 158,64 mg/L de P respectivement par H3-5 et L1. Cette dissolution biologique de phosphore inorganique est accompagnée par une diminution de pH du milieu, et l'intensité de cette acidification diff...
Current Plant Science and Biotechnology in Agriculture, 2008
ABSTRACT Over the last 3 decades, soil in the north of Morocco has been heavily degraded as a res... more ABSTRACT Over the last 3 decades, soil in the north of Morocco has been heavily degraded as a result of human activities. In the north of Morocco, particularly the Rif occidental, there is strong anthropozoogenic pressure, through the practice of clearing the land to profit from the extension of Cannabis culture and an increase in the frequency of forest fires. These factors threaten the survival of the shrubby legume in its ecological niche.
Journal of infection in developing countries, 2010
Flies and cockroaches are two insects in close contact with human beings. They are carriers of hu... more Flies and cockroaches are two insects in close contact with human beings. They are carriers of human pathogenic bacteria on the external areas of their bodies or in their digestive tracts. This study examines Periplaneta americana and Musca domestica collected from the residential areas of six districts in Tangier, Morocco. In total, 251 bacteria were isolated from external areas of the participants' bodies and the antimicrobial susceptibility was calculated. The predominant bacterial species included Escherichia coli (17.9%), Klebsiella spp. (14.7%), Providencia spp. (9.6%), Staphylococcus spp. (15.1%) and Enterococcus spp. (11.6%). The study showed no difference between the species of bacterial strains from American cockroaches and houseflies. Carbapenems and aminoglycosides were active against 100% of the Gram-negative bacilli isolated in this study. Staphylococcus spp. strains were susceptible to linezolid, vancomycin, daptomycin, levofloxacin and cotrimoxazole, and no antib...
Journal of infection in developing countries, 2009
This study aimed to investigate Salmonella Enteritidis strains isolated from human and food sourc... more This study aimed to investigate Salmonella Enteritidis strains isolated from human and food sources in the north of Morocco by means of phenotypic and genotypic methods. Fifteen isolates from humans and food were submitted to phage typing, XbaI-macrorestriction (pulsed field gel electrophoresis [PFGE]), enterobacterial repetitive intergenic consensus (ERIC-PCR), antimicrobial susceptibility testing, and PCR assay targeting the spvR and invA genes. Six fingerprinting profiles were obtained with the ERIC-PCR method, four with PFGE profiling, five with antimicrobial resistance, three with phage typing, and only one with plasmid profiling. spvR gene was detected in six strains, which did not harbour plasmids of 90 kb. The conclusions of this study are drawn from a limited number of isolates. It would be desirable to investigate a greater and more diverse population of Salmonella isolates. S. Enteritidis was genotyped and showed four different patterns by PFGE and six by ERIC-PCR. Accord...
World Journal of Microbiology and Biotechnology, 2008
Page 1. ORIGINAL PAPER Characterization of a bacteriocin-producing strain of Enterococcus faecali... more Page 1. ORIGINAL PAPER Characterization of a bacteriocin-producing strain of Enterococcus faecalis from cow's milk used in the production of Moroccan traditional dairy foods Ghada Choho Æ Hikmate Abriouel Æ Nabil Ben ...
The uncontrolled disposal of bottom ash generated by the incineration units of hazardous and infe... more The uncontrolled disposal of bottom ash generated by the incineration units of hazardous and infected wastes in developed countries are the main cause of significant damage, such as contamination of the soil, as well as surface and underground waters, which may put both the environment and public health at risk. In Morocco, little information is available on the chemical properties of the resulting ashes. In this study, 16 hospital waste ash samples were collected from the incinerators of the two main hospitals in Rabat: Ibn Sina and Cheikh Zayd. A series of tests was conducted, including particle size distribution, mineralogical and chemical composition, and heavy metal leaching behaviour. The results showed that the samples were composed mainly of P2O5 (18%), SiO2 (17%), Na2O (16%), CaO (14%) and SO3 (10%). Moreover, chemical analysis clearly demonstrated that medical waste (MW) contains large amounts of waste generated by domestic activities in the hospital, with a lack of sorting system in the monitoring of MW. Furthermore, the ashes contained high concentrations of heavy metals such as zinc, lead, chromium and nickel with a vast range of 0.5-25071 mg/kg. Leaching tests showed that the extracted amounts of all the heavy metals were lower, with concentrations < 2.85 mg/kg. Comparison of the corresponding heavy metal concentrations with the limit values set by the Council Decision 2003/33/EC allowed us to conclude that bottom ashes meet the waste acceptance criteria regarding these heavy metals.
Lipolysis, primary proteolysis and secondary proteolysis during ripening of a goats' milk che... more Lipolysis, primary proteolysis and secondary proteolysis during ripening of a goats' milk cheese manufactured with commercial starter (A), commercial rennet and starter culture (B) and starter culture (C) were studied. The concentration of acetic acid and total C4:0–C18:2 FFA in cheeses A, B and C, increased throughout ripening. The total FFA contents in cheese A and B was significantly higher (P < 0.05) from those in cheese C throughout ripening. The short chain FFAs represented approximately 13, 14 and 14% of the TFFA content in cheeses A, B and C respectively, at 5 d. The percentage of medium chain FFAs (C10:0–C14:0) representing approximately 28, 29 and 38% of total FFAs in cheeses A, B and C respectively, at 5 d. The percentages of long chain FFAs (C16:0–C18:2) represented approximately 59, 58 and 48% in cheeses A, B and C respectively, at 5 d. In Moroccan goat's cheese, intense proteolytic activity took place during ripening. In the cheeses produced with commercial ...
ABSTRACT: In the first part of this study, we were proceeded tothe evaluation of the antibacteria... more ABSTRACT: In the first part of this study, we were proceeded tothe evaluation of the antibacterial effect of the organicextracts from the leaves of three plant species of Menthaagainst six pathogenic bacterial strains including Gram (-)bacteria and Gram (+) bacteria. The methods of diffusionin solid and micro-dilution method in liquid medium wereused for antibacterial testing. The results showed that nonpolarextracts are much more active then polar extracts. TheGram (+) bacteria showed more sensitive than the Gram (-)bacteria. S. aureus was shown to be the most sensitive of allbacteria testing in this study, it was sensitive against allextracts include that aqueous. All aqueous extracts haveno antibacterial activity with the highest concentration used(12 mg/ml) against the five other strains. In the second part, non-polar extracts were tested for their anti-biofilm effect against biofilms formed by S. aureus and E. coli in 48 hours. All extracts showed a spectacular antibiofilm effect with elimination of all the biofilms formed after 30 min of treatment.
The present study aims to assess the effect of phosphate solubilizing bacteria (PSB) in interacti... more The present study aims to assess the effect of phosphate solubilizing bacteria (PSB) in interaction with native arbuscular mycorrhizal fungi (AMF) and rhizobia on peanut growth cultivated in the Northwest of Morocco. To perform this aim, seeds were inoculated with 5 PSB strains: PP22, GP70, GR1, PR29, and GR70, and then grown in unsterilized soil collected from peanut fields. Plant harvesting was made after 8 weeks of growth under chamber conditions. The results demonstrated that PSB treatments showed positive effect on mycorrhizal colonization, nodulation and plant growth parameters. The best results were found with Pseudomonas strains, GP70, PP22 and GR1. This study indicates the great potential of some PSB to improve yield and nutrient uptake of peanut plants in the presence of native rhizobia and AMF. They could serve as biofertilizers, minimizing chemical fertilization that is currently used to obtain high yields for peanut agriculture. Keywords: AMF, growth, peanut, PSB, rhizobia
This work exposes the analysis and the modeling of the kinetics of desiccation of strawberries du... more This work exposes the analysis and the modeling of the kinetics of desiccation of strawberries during the freeze-drying process. A lyophilisator Virtis 35L Gardiner was used. Freeze-drying was carried out at various temperatures. The impact study of the various parameters of freeze-drying process of Moroccan strawberries showed that the temperature has an important incidence on the reduction process duration, thus minimizing the cost of the process while preserving the quality of the dry fruit and opening the field with the application of this technology to the treatment of new food products.
The development of a biological alternative to chemical fertilizers is of great importance for th... more The development of a biological alternative to chemical fertilizers is of great importance for the improvement of agriculture as well as protection of the environment. Achieving this goal, 305 bacteria were isolated from thé rhizosphere of rice fields in Northwestern Morocco, of which 136 rhizobacteria were tricalcique phosphate solubilizers. Based on diameter of solubilization halos, the 17 best phosphate solubilizers, Gram-negative, were selected. Six isolates were able to produce the indole acetic acid, while 3 bacteria were positive for hydrogel cyanide synthesis. Nine bacteria were chosen for more activities. Except the isolate P66, all bacteria were siderophores producers. No bacteria fixed nitrogen, while ACC deaminase was detected in three bacteria, E34, E68 and E85.The solubilization of other inorganic forms of insoluble phosphate was quantitatively evaluated and all isolates couldn t dissolve both forms FePO4 and AlPO4, while 7 bacteria were found to be Ca5HO13P3 and CaHPO...
Ce travail présente l'étude de la solubilisation de phosphate tricalcique par des Rhizobium i... more Ce travail présente l'étude de la solubilisation de phosphate tricalcique par des Rhizobium isolés des nodules de trois légumineuses (Hydesarum coronarium, Vicia sativa, et Lupinus angustifolius), et tester leur effet sur la germination des semences du triticale, variété Momtaz. Dans un premier temps, les 53 isolats obtenus ont été testés sur milieu PVK solide renfermant 0,5% de phosphate tricalcique (PTC), afin de garder ceux ayant l'activité solubilisatrice de PTC. Ainsi, six isolats (H2-7, H2-10, H3-5, L1, L2 et L5) ont donné des halos de solubilisation de diamètre oscillant entre 0,3 cm et 0,6 cm. Par la suite, ces isolats ont été soumis au test quantitatif dans le milieu PVK liquide en mesurant le P solubilisé et le pH. Les résultats obtenus sont compris entre 9,62 mg/L et 158,64 mg/L de P respectivement par H3-5 et L1. Cette dissolution biologique de phosphore inorganique est accompagnée par une diminution de pH du milieu, et l'intensité de cette acidification diff...
Current Plant Science and Biotechnology in Agriculture, 2008
ABSTRACT Over the last 3 decades, soil in the north of Morocco has been heavily degraded as a res... more ABSTRACT Over the last 3 decades, soil in the north of Morocco has been heavily degraded as a result of human activities. In the north of Morocco, particularly the Rif occidental, there is strong anthropozoogenic pressure, through the practice of clearing the land to profit from the extension of Cannabis culture and an increase in the frequency of forest fires. These factors threaten the survival of the shrubby legume in its ecological niche.
Journal of infection in developing countries, 2010
Flies and cockroaches are two insects in close contact with human beings. They are carriers of hu... more Flies and cockroaches are two insects in close contact with human beings. They are carriers of human pathogenic bacteria on the external areas of their bodies or in their digestive tracts. This study examines Periplaneta americana and Musca domestica collected from the residential areas of six districts in Tangier, Morocco. In total, 251 bacteria were isolated from external areas of the participants' bodies and the antimicrobial susceptibility was calculated. The predominant bacterial species included Escherichia coli (17.9%), Klebsiella spp. (14.7%), Providencia spp. (9.6%), Staphylococcus spp. (15.1%) and Enterococcus spp. (11.6%). The study showed no difference between the species of bacterial strains from American cockroaches and houseflies. Carbapenems and aminoglycosides were active against 100% of the Gram-negative bacilli isolated in this study. Staphylococcus spp. strains were susceptible to linezolid, vancomycin, daptomycin, levofloxacin and cotrimoxazole, and no antib...
Journal of infection in developing countries, 2009
This study aimed to investigate Salmonella Enteritidis strains isolated from human and food sourc... more This study aimed to investigate Salmonella Enteritidis strains isolated from human and food sources in the north of Morocco by means of phenotypic and genotypic methods. Fifteen isolates from humans and food were submitted to phage typing, XbaI-macrorestriction (pulsed field gel electrophoresis [PFGE]), enterobacterial repetitive intergenic consensus (ERIC-PCR), antimicrobial susceptibility testing, and PCR assay targeting the spvR and invA genes. Six fingerprinting profiles were obtained with the ERIC-PCR method, four with PFGE profiling, five with antimicrobial resistance, three with phage typing, and only one with plasmid profiling. spvR gene was detected in six strains, which did not harbour plasmids of 90 kb. The conclusions of this study are drawn from a limited number of isolates. It would be desirable to investigate a greater and more diverse population of Salmonella isolates. S. Enteritidis was genotyped and showed four different patterns by PFGE and six by ERIC-PCR. Accord...
World Journal of Microbiology and Biotechnology, 2008
Page 1. ORIGINAL PAPER Characterization of a bacteriocin-producing strain of Enterococcus faecali... more Page 1. ORIGINAL PAPER Characterization of a bacteriocin-producing strain of Enterococcus faecalis from cow's milk used in the production of Moroccan traditional dairy foods Ghada Choho Æ Hikmate Abriouel Æ Nabil Ben ...
The uncontrolled disposal of bottom ash generated by the incineration units of hazardous and infe... more The uncontrolled disposal of bottom ash generated by the incineration units of hazardous and infected wastes in developed countries are the main cause of significant damage, such as contamination of the soil, as well as surface and underground waters, which may put both the environment and public health at risk. In Morocco, little information is available on the chemical properties of the resulting ashes. In this study, 16 hospital waste ash samples were collected from the incinerators of the two main hospitals in Rabat: Ibn Sina and Cheikh Zayd. A series of tests was conducted, including particle size distribution, mineralogical and chemical composition, and heavy metal leaching behaviour. The results showed that the samples were composed mainly of P2O5 (18%), SiO2 (17%), Na2O (16%), CaO (14%) and SO3 (10%). Moreover, chemical analysis clearly demonstrated that medical waste (MW) contains large amounts of waste generated by domestic activities in the hospital, with a lack of sorting system in the monitoring of MW. Furthermore, the ashes contained high concentrations of heavy metals such as zinc, lead, chromium and nickel with a vast range of 0.5-25071 mg/kg. Leaching tests showed that the extracted amounts of all the heavy metals were lower, with concentrations &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 2.85 mg/kg. Comparison of the corresponding heavy metal concentrations with the limit values set by the Council Decision 2003/33/EC allowed us to conclude that bottom ashes meet the waste acceptance criteria regarding these heavy metals.
Lipolysis, primary proteolysis and secondary proteolysis during ripening of a goats' milk che... more Lipolysis, primary proteolysis and secondary proteolysis during ripening of a goats' milk cheese manufactured with commercial starter (A), commercial rennet and starter culture (B) and starter culture (C) were studied. The concentration of acetic acid and total C4:0–C18:2 FFA in cheeses A, B and C, increased throughout ripening. The total FFA contents in cheese A and B was significantly higher (P < 0.05) from those in cheese C throughout ripening. The short chain FFAs represented approximately 13, 14 and 14% of the TFFA content in cheeses A, B and C respectively, at 5 d. The percentage of medium chain FFAs (C10:0–C14:0) representing approximately 28, 29 and 38% of total FFAs in cheeses A, B and C respectively, at 5 d. The percentages of long chain FFAs (C16:0–C18:2) represented approximately 59, 58 and 48% in cheeses A, B and C respectively, at 5 d. In Moroccan goat's cheese, intense proteolytic activity took place during ripening. In the cheeses produced with commercial ...
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