Objective Gas chromatography （GC） was used to investigate the cellular fatty acid （CFA） composition of 141 Acinetobacter boumannii and 32 A. calcoaceticus isolates from different locations in China and to find che...Objective Gas chromatography （GC） was used to investigate the cellular fatty acid （CFA） composition of 141 Acinetobacter boumannii and 32 A. calcoaceticus isolates from different locations in China and to find chemical markers to differentiate these two closely related bacteria. Methods Whole cell fatty acid methyl esters （FAMEs） were obtained by saponification, methylation, and extraction for GC analysis, followed by a standardized Microbial Identification System （MIS） analysis. Results All A. baumannii and A. calcoaceticus strains contained some major fatty acids, namely, 18：1 co9c, 16：0, Sum In Feature 3, 12：0, 17：1co8c, 3-OH-12：0, 17：0, Sum In Feature 2, 2-OH-12：0, and 18：0 compounds. Although most of the total CFAs are similar between A. baumannii and A. calcoaceticus strains, the ratios of two pairs of CFAs, i.e., Sum In Feature 3/18：1 co9c versus 16：0/18：1 co9c and Sum In Feature 3/18：1 co9c versus unknown 12.484/18：1 co9c fatty acids, could differentiate these two closely related bacteria. A. baumannii could be easily classified into two subgroups by plotting some ratios such as Sum In Feature 3/16：0 versus 17：0 and Sum In Feature 3/2-OH-12：0 versus17：0 fatty acids. Conclusion The ratios of some CFAs could be used as chemical markers to distinguish A. baumannii from A. colcoaceticus.展开更多
Pharmaceutical residues have become tightly controlled environmental contaminants in recent years, due to their increasing concentration in environmental components. This is mainly caused by their high level of produc...Pharmaceutical residues have become tightly controlled environmental contaminants in recent years, due to their increasing concentration in environmental components. This is mainly caused by their high level of production and everyday consumption. Therefore there is a need to apply new and sufficiently sensitive analytical methods, which can detect the presence of these contaminants even in very low concentrations. This study is focused on the application of a reliable analytical method for the analysis of 10 selected drug residues, mainly from the group of non-steroidal anti-inflammatory drugs （salicylic acid, acetylsalicylic acid, ctofibric acid, ibuprofen, acetaminophen, caffeine, naproxen, mefenamic acid, ketoprofen, and dicofenac）, in wastewaters and surface waters. This analytical method is based on solid phase extraction, derivatization by N-methyl-N-（trimethylsilyl）trifluoroacetamide （MSTFA） and finally analysis by comprehensive two-dimensional gas chromatography with Time-of-Flight mass spectrometric detection （GC×GC- TOF MS）. Detection limits ranged from 0.18 to 5 ng/L depending on the compound and selected matrix. The method was successfully applied for detection of the presence of selected pharmaceuticals in the Svratka River and in wastewater from the wastewater treatment plant in Brno-Modrice, Czech Republic. The concentration of pharmaceuticals varied from one to several hundreds of ng/L in surface water and from one to several tens of μg/L in wastewater.展开更多
基金supported by the Innovation Foundation of Shanxi Medical University for undergraduate students (No. 2009056)the National Key Program for Infectious Diseases of China (No. 2008ZX10004-009)
文摘Objective Gas chromatography （GC） was used to investigate the cellular fatty acid （CFA） composition of 141 Acinetobacter boumannii and 32 A. calcoaceticus isolates from different locations in China and to find chemical markers to differentiate these two closely related bacteria. Methods Whole cell fatty acid methyl esters （FAMEs） were obtained by saponification, methylation, and extraction for GC analysis, followed by a standardized Microbial Identification System （MIS） analysis. Results All A. baumannii and A. calcoaceticus strains contained some major fatty acids, namely, 18：1 co9c, 16：0, Sum In Feature 3, 12：0, 17：1co8c, 3-OH-12：0, 17：0, Sum In Feature 2, 2-OH-12：0, and 18：0 compounds. Although most of the total CFAs are similar between A. baumannii and A. calcoaceticus strains, the ratios of two pairs of CFAs, i.e., Sum In Feature 3/18：1 co9c versus 16：0/18：1 co9c and Sum In Feature 3/18：1 co9c versus unknown 12.484/18：1 co9c fatty acids, could differentiate these two closely related bacteria. A. baumannii could be easily classified into two subgroups by plotting some ratios such as Sum In Feature 3/16：0 versus 17：0 and Sum In Feature 3/2-OH-12：0 versus17：0 fatty acids. Conclusion The ratios of some CFAs could be used as chemical markers to distinguish A. baumannii from A. colcoaceticus.
基金supported by the Institute Research Plan(No. FCH-S-12-4) from the Ministry of Education,Youth and Sports of the Czech Republic
文摘Pharmaceutical residues have become tightly controlled environmental contaminants in recent years, due to their increasing concentration in environmental components. This is mainly caused by their high level of production and everyday consumption. Therefore there is a need to apply new and sufficiently sensitive analytical methods, which can detect the presence of these contaminants even in very low concentrations. This study is focused on the application of a reliable analytical method for the analysis of 10 selected drug residues, mainly from the group of non-steroidal anti-inflammatory drugs （salicylic acid, acetylsalicylic acid, ctofibric acid, ibuprofen, acetaminophen, caffeine, naproxen, mefenamic acid, ketoprofen, and dicofenac）, in wastewaters and surface waters. This analytical method is based on solid phase extraction, derivatization by N-methyl-N-（trimethylsilyl）trifluoroacetamide （MSTFA） and finally analysis by comprehensive two-dimensional gas chromatography with Time-of-Flight mass spectrometric detection （GC×GC- TOF MS）. Detection limits ranged from 0.18 to 5 ng/L depending on the compound and selected matrix. The method was successfully applied for detection of the presence of selected pharmaceuticals in the Svratka River and in wastewater from the wastewater treatment plant in Brno-Modrice, Czech Republic. The concentration of pharmaceuticals varied from one to several hundreds of ng/L in surface water and from one to several tens of μg/L in wastewater.
