To determine the occurrence of Enterobacter sakazakii and other Enerobateriaceae in commercial powdered infant formula (PIF), 185 packages of PIF from different manufacturers, supermarkets and drug-stores in Abidjan w...To determine the occurrence of Enterobacter sakazakii and other Enerobateriaceae in commercial powdered infant formula (PIF), 185 packages of PIF from different manufacturers, supermarkets and drug-stores in Abidjan were analyzed. Ten g of sample was homogenized in 90 ml of buffered peptone water (PBW, Biorad, Paris) for further studies. Enterobacteriaceae (coliforms) were enumerated according to French Association of Standardization methods. E. sakazakii was detected according to Kandhai’s method. Bacteria were identified using API20 system. Thirty-eight samples (20.5%) were positive for Enterobacteriaceae. Twenty-four samples (13%) yielded Enterobacter sakazakii. Other Enterobacteriaceae isolated included Pantoea spp. 21 (11.5%), Klebsiella pneumoniae subsp. Pneumonia 8 (4.3%), Citrobacter diversus 1 (0.5%), Citrobacter freundii 1 (0.5%), Enterobacter cloacae 1 (0.5%), Salmonella reading 1 (0.5%), Serratia ficara 1 (0.5%) Serratia odorifera 1 (0.5%). This study is the first report to describe the contamination of PIF from Abidjan with E. sakazakii and several other Enterobacteriaceae that could be opportunistic pathogens. Therefore, well-controlled studies need to be conducted to assess the extent of risk associated with contaminated PIF for infants in Abidjan.展开更多
A widespread use of acrylamide, probably a neurotoxicant and carcinogen, in various industrial processes has led to environmental contamination. Fortunately, some microorganisms are able to derive energy from acrylami...A widespread use of acrylamide, probably a neurotoxicant and carcinogen, in various industrial processes has led to environmental contamination. Fortunately, some microorganisms are able to derive energy from acrylamide. In the present work, we reported the isolation and characterization of a novel acrylamide-degrading bacterium from domestic wastewater in Chonburi, Thailand. The strain grew well in the presence of acrylamide as 0.5% （W/V）, at pH 6.0 to 9,0 and 25℃. Identification based on biochemical characteristics and 16S rRNA gene sequence identified the strain as Enterobacter aerogenes. Degradation of acrylamide to acrylic acid started in the late logarithmic growth phase as a biomass-dependent pattern. Specificity of cell-free supernatant towards amides completely degraded butyramide and urea and 86% of lactamide. Moderate degradation took place in other amides with that by formanaide 〉 benzamide 〉 acetamide 〉 cyanoacetamide 〉 propionamide. No degradation was detected in the reactions of N,N-methylene bisacrylamide, sodium azide, thioacetamide, and iodoacetamide. These results highlighted the potential of this bacterium in the cleanup of acrylamide/amide in the environment.展开更多
文摘To determine the occurrence of Enterobacter sakazakii and other Enerobateriaceae in commercial powdered infant formula (PIF), 185 packages of PIF from different manufacturers, supermarkets and drug-stores in Abidjan were analyzed. Ten g of sample was homogenized in 90 ml of buffered peptone water (PBW, Biorad, Paris) for further studies. Enterobacteriaceae (coliforms) were enumerated according to French Association of Standardization methods. E. sakazakii was detected according to Kandhai’s method. Bacteria were identified using API20 system. Thirty-eight samples (20.5%) were positive for Enterobacteriaceae. Twenty-four samples (13%) yielded Enterobacter sakazakii. Other Enterobacteriaceae isolated included Pantoea spp. 21 (11.5%), Klebsiella pneumoniae subsp. Pneumonia 8 (4.3%), Citrobacter diversus 1 (0.5%), Citrobacter freundii 1 (0.5%), Enterobacter cloacae 1 (0.5%), Salmonella reading 1 (0.5%), Serratia ficara 1 (0.5%) Serratia odorifera 1 (0.5%). This study is the first report to describe the contamination of PIF from Abidjan with E. sakazakii and several other Enterobacteriaceae that could be opportunistic pathogens. Therefore, well-controlled studies need to be conducted to assess the extent of risk associated with contaminated PIF for infants in Abidjan.
基金Financial support was mainly provided to JittimaCharoenpanich from Center of Excellence on Environmental Health,Toxicology and Management of Chemicals(ETM-PERDO)partly from Faculty of Science,Burapha Universitya scholarship support to Kanokhathai Buranasilp from Center of Excellence for Innovation in Chemistry (PERCH-CIC),Commission on Higher Education,Ministry of Education
文摘A widespread use of acrylamide, probably a neurotoxicant and carcinogen, in various industrial processes has led to environmental contamination. Fortunately, some microorganisms are able to derive energy from acrylamide. In the present work, we reported the isolation and characterization of a novel acrylamide-degrading bacterium from domestic wastewater in Chonburi, Thailand. The strain grew well in the presence of acrylamide as 0.5% （W/V）, at pH 6.0 to 9,0 and 25℃. Identification based on biochemical characteristics and 16S rRNA gene sequence identified the strain as Enterobacter aerogenes. Degradation of acrylamide to acrylic acid started in the late logarithmic growth phase as a biomass-dependent pattern. Specificity of cell-free supernatant towards amides completely degraded butyramide and urea and 86% of lactamide. Moderate degradation took place in other amides with that by formanaide 〉 benzamide 〉 acetamide 〉 cyanoacetamide 〉 propionamide. No degradation was detected in the reactions of N,N-methylene bisacrylamide, sodium azide, thioacetamide, and iodoacetamide. These results highlighted the potential of this bacterium in the cleanup of acrylamide/amide in the environment.
