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Gerd Hamscher - One of the best experts on this subject based on the ideXlab platform.
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biotransformation of the antibiotic danofloxacin by xylaria longipes leads to an efficient reduction of its antibacterial activity
Journal of Agricultural and Food Chemistry, 2015Co-Authors: Marina Rusch, Annika Kauschat, Astrid Spielmeyer, Andreas Rompp, Heike Hausmann, Holger Zorn, Gerd HamscherAbstract:Fluoroquinolones are considered as critically important antibiotics. However, they are used in appreciable quantities in veterinary medicine. Liquid Manure and feces can contain substantial amounts of unmetabolized antibiotics and, thus, antibiotics can enter the environment if Manure is used for soil fertilization. In this study, the microbial biotransformation of the synthetic veterinary fluoroquinolone danofloxacin by the ascomycete Xylaria longipes was investigated. Fungal submerged cultures led to a regioselective and almost quantitative formation of a single metabolite within 3 days. The metabolite was unequivocally identified as danofloxacin N-oxide by high-resolution mass spectrometry and one- and two-dimensional nuclear magnetic resonance spectroscopic techniques. An oxidation of the terminal nitrogen of the substituted piperazine moiety of the substance led to a remarkable reduction of 80% of the initial antibacterial activity. Thus, fungal enzymes involved in the biotransformation process might...
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different behavior of tetracyclines and sulfonamides in sandy soils after repeated fertilization with Liquid Manure
Environmental Toxicology and Chemistry, 2005Co-Authors: Gerd Hamscher, Heinrich Hoper, Heike Theresia Pawelzick, Heinz NauAbstract:Recently we showed that tetracyclines tend to persist and may accumulate in sandy soils after repeated fertilizations with Liquid Manure. We continued these field investigations from 2001 to 2003 and observed no further accumulation of tetracyclines in soil, but found that the average tetracycline concentration remained higher than 150 μg/kg soil. From 2000 to 2002, approximately 330 g tetracycline, 7 g chlortetracycline, 28 g sulfamethazine, and 57 g sulfadiazine per hectare were transferred via Liquid Manure to the topsoil (0–30 cm). Nevertheless, no leaching of tetracyclines into deeper soil segments or groundwater was observed. Furthermore, we developed new analytical methods for the detection of various sulfonamides in Liquid Manure, soil, and groundwater. Investigation of the same fields used in the tetracycline study showed that sulfamethazine occurred in concentrations approximately two orders of magnitude lower than that of tetracycline in the plow layer. Although there apparently were very low concentrations of sulfamethazine in soil, we detected it in groundwater sampled by suction probes at 1.4 m below soil surface in the spring of 2002. Further investigations confirmed these findings. To our knowledge, this is the first direct evidence of continuous leaching of a veterinary drug from soil into groundwater under field conditions. We conclude that tetracyclines and sulfonamides show distinctly different environmental behaviors. One explanation may be their different sorption coefficients in soil, indicating (in part) their different mobilities in this ecosystem.
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determination of persistent tetracycline residues in soil fertilized with Liquid Manure by high performance Liquid chromatography with electrospray ionization tandem mass spectrometry
Analytical Chemistry, 2002Co-Authors: Gerd Hamscher, Silke Sczesny, Heinrich HoperAbstract:Little is known about the occurrence and the fate of veterinary drugs in the environment. Therefore, a Liquid chromatography/tandem mass spectrometry method was developed and employed to investigate in detail the distribution and persistence of the frequently used tetracyclines and tylosin in a field fertilized with Liquid Manure on April 2000 and April 2001; soil sampling was performed in May 2000, November 2000, and May 2001. We detected 4.0 mg/kg tetracycline and 0.1 mg/kg chlortetracycline in the Liquid Manure of April 2000, as well as comparable amounts in the Liquid Manure of April 2001. In the soil samples of May 2001, the highest average concentrations of 86.2 (0−10 cm), 198.7 (10−20 cm), and 171.7 μg/kg (20−30 cm) tetracycline and 4.6−7.3 μg/kg chlortetracycline (all three sublayers) were found. At soil depths between 30 and 90 cm, as well as in soil or groundwater, tetracyclines could not be detected. In addition, oxytetracycline and tylosin could not be detected in any sample investigated. We c...
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determination of persistent tetracycline residues in soil fertilized with Liquid Manure by high performance Liquid chromatography with electrospray ionization tandem mass spectrometry
Analytical Chemistry, 2002Co-Authors: Gerd Hamscher, Silke Sczesny, Heinrich Hoper, Heinz NauAbstract:Little is known about the occurrence and the fate of veterinary drugs in the environment. Therefore, a Liquid chromatography/tandem mass spectrometry method was developed and employed to investigate in detail the distribution and persistence of the frequently used tetracyclines and tylosin in a field fertilized with Liquid Manure on April 2000 and April 2001; soil sampling was performed in May 2000, November 2000, and May 2001. We detected 4.0 mg/kg tetracycline and 0.1 mg/kg chlortetracycline in the Liquid Manure of April 2000, as well as comparable amounts in the Liquid Manure of April 2001. In the soil samples of May 2001, the highest average concentrations of 86.2 (0-10 cm), 198.7 (10-20 cm), and 171.7 microg/kg (20-30 cm) tetracycline and 4.6-7.3 micro/kg chlortetracycline (all three sublayers) were found. At soil depths between 30 and 90 cm, as well as in soil or groundwater, tetracyclines could not be detected. In addition, oxytetracycline and tylosin could not be detected in any sample investigated. We conclude that tetracyclines enter the environment in significant concentrations via repeated fertilizations with Liquid Manure, build up persistent residues, and accumulate in soil. Therefore, tetracyclines may have a potential risk and investigations on the environmental effects of these antibiotics are necessary.
Heinrich Hoper - One of the best experts on this subject based on the ideXlab platform.
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different behavior of tetracyclines and sulfonamides in sandy soils after repeated fertilization with Liquid Manure
Environmental Toxicology and Chemistry, 2005Co-Authors: Gerd Hamscher, Heinrich Hoper, Heike Theresia Pawelzick, Heinz NauAbstract:Recently we showed that tetracyclines tend to persist and may accumulate in sandy soils after repeated fertilizations with Liquid Manure. We continued these field investigations from 2001 to 2003 and observed no further accumulation of tetracyclines in soil, but found that the average tetracycline concentration remained higher than 150 μg/kg soil. From 2000 to 2002, approximately 330 g tetracycline, 7 g chlortetracycline, 28 g sulfamethazine, and 57 g sulfadiazine per hectare were transferred via Liquid Manure to the topsoil (0–30 cm). Nevertheless, no leaching of tetracyclines into deeper soil segments or groundwater was observed. Furthermore, we developed new analytical methods for the detection of various sulfonamides in Liquid Manure, soil, and groundwater. Investigation of the same fields used in the tetracycline study showed that sulfamethazine occurred in concentrations approximately two orders of magnitude lower than that of tetracycline in the plow layer. Although there apparently were very low concentrations of sulfamethazine in soil, we detected it in groundwater sampled by suction probes at 1.4 m below soil surface in the spring of 2002. Further investigations confirmed these findings. To our knowledge, this is the first direct evidence of continuous leaching of a veterinary drug from soil into groundwater under field conditions. We conclude that tetracyclines and sulfonamides show distinctly different environmental behaviors. One explanation may be their different sorption coefficients in soil, indicating (in part) their different mobilities in this ecosystem.
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determination of persistent tetracycline residues in soil fertilized with Liquid Manure by high performance Liquid chromatography with electrospray ionization tandem mass spectrometry
Analytical Chemistry, 2002Co-Authors: Gerd Hamscher, Silke Sczesny, Heinrich HoperAbstract:Little is known about the occurrence and the fate of veterinary drugs in the environment. Therefore, a Liquid chromatography/tandem mass spectrometry method was developed and employed to investigate in detail the distribution and persistence of the frequently used tetracyclines and tylosin in a field fertilized with Liquid Manure on April 2000 and April 2001; soil sampling was performed in May 2000, November 2000, and May 2001. We detected 4.0 mg/kg tetracycline and 0.1 mg/kg chlortetracycline in the Liquid Manure of April 2000, as well as comparable amounts in the Liquid Manure of April 2001. In the soil samples of May 2001, the highest average concentrations of 86.2 (0−10 cm), 198.7 (10−20 cm), and 171.7 μg/kg (20−30 cm) tetracycline and 4.6−7.3 μg/kg chlortetracycline (all three sublayers) were found. At soil depths between 30 and 90 cm, as well as in soil or groundwater, tetracyclines could not be detected. In addition, oxytetracycline and tylosin could not be detected in any sample investigated. We c...
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determination of persistent tetracycline residues in soil fertilized with Liquid Manure by high performance Liquid chromatography with electrospray ionization tandem mass spectrometry
Analytical Chemistry, 2002Co-Authors: Gerd Hamscher, Silke Sczesny, Heinrich Hoper, Heinz NauAbstract:Little is known about the occurrence and the fate of veterinary drugs in the environment. Therefore, a Liquid chromatography/tandem mass spectrometry method was developed and employed to investigate in detail the distribution and persistence of the frequently used tetracyclines and tylosin in a field fertilized with Liquid Manure on April 2000 and April 2001; soil sampling was performed in May 2000, November 2000, and May 2001. We detected 4.0 mg/kg tetracycline and 0.1 mg/kg chlortetracycline in the Liquid Manure of April 2000, as well as comparable amounts in the Liquid Manure of April 2001. In the soil samples of May 2001, the highest average concentrations of 86.2 (0-10 cm), 198.7 (10-20 cm), and 171.7 microg/kg (20-30 cm) tetracycline and 4.6-7.3 micro/kg chlortetracycline (all three sublayers) were found. At soil depths between 30 and 90 cm, as well as in soil or groundwater, tetracyclines could not be detected. In addition, oxytetracycline and tylosin could not be detected in any sample investigated. We conclude that tetracyclines enter the environment in significant concentrations via repeated fertilizations with Liquid Manure, build up persistent residues, and accumulate in soil. Therefore, tetracyclines may have a potential risk and investigations on the environmental effects of these antibiotics are necessary.
Heinz Nau - One of the best experts on this subject based on the ideXlab platform.
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different behavior of tetracyclines and sulfonamides in sandy soils after repeated fertilization with Liquid Manure
Environmental Toxicology and Chemistry, 2005Co-Authors: Gerd Hamscher, Heinrich Hoper, Heike Theresia Pawelzick, Heinz NauAbstract:Recently we showed that tetracyclines tend to persist and may accumulate in sandy soils after repeated fertilizations with Liquid Manure. We continued these field investigations from 2001 to 2003 and observed no further accumulation of tetracyclines in soil, but found that the average tetracycline concentration remained higher than 150 μg/kg soil. From 2000 to 2002, approximately 330 g tetracycline, 7 g chlortetracycline, 28 g sulfamethazine, and 57 g sulfadiazine per hectare were transferred via Liquid Manure to the topsoil (0–30 cm). Nevertheless, no leaching of tetracyclines into deeper soil segments or groundwater was observed. Furthermore, we developed new analytical methods for the detection of various sulfonamides in Liquid Manure, soil, and groundwater. Investigation of the same fields used in the tetracycline study showed that sulfamethazine occurred in concentrations approximately two orders of magnitude lower than that of tetracycline in the plow layer. Although there apparently were very low concentrations of sulfamethazine in soil, we detected it in groundwater sampled by suction probes at 1.4 m below soil surface in the spring of 2002. Further investigations confirmed these findings. To our knowledge, this is the first direct evidence of continuous leaching of a veterinary drug from soil into groundwater under field conditions. We conclude that tetracyclines and sulfonamides show distinctly different environmental behaviors. One explanation may be their different sorption coefficients in soil, indicating (in part) their different mobilities in this ecosystem.
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determination of persistent tetracycline residues in soil fertilized with Liquid Manure by high performance Liquid chromatography with electrospray ionization tandem mass spectrometry
Analytical Chemistry, 2002Co-Authors: Gerd Hamscher, Silke Sczesny, Heinrich Hoper, Heinz NauAbstract:Little is known about the occurrence and the fate of veterinary drugs in the environment. Therefore, a Liquid chromatography/tandem mass spectrometry method was developed and employed to investigate in detail the distribution and persistence of the frequently used tetracyclines and tylosin in a field fertilized with Liquid Manure on April 2000 and April 2001; soil sampling was performed in May 2000, November 2000, and May 2001. We detected 4.0 mg/kg tetracycline and 0.1 mg/kg chlortetracycline in the Liquid Manure of April 2000, as well as comparable amounts in the Liquid Manure of April 2001. In the soil samples of May 2001, the highest average concentrations of 86.2 (0-10 cm), 198.7 (10-20 cm), and 171.7 microg/kg (20-30 cm) tetracycline and 4.6-7.3 micro/kg chlortetracycline (all three sublayers) were found. At soil depths between 30 and 90 cm, as well as in soil or groundwater, tetracyclines could not be detected. In addition, oxytetracycline and tylosin could not be detected in any sample investigated. We conclude that tetracyclines enter the environment in significant concentrations via repeated fertilizations with Liquid Manure, build up persistent residues, and accumulate in soil. Therefore, tetracyclines may have a potential risk and investigations on the environmental effects of these antibiotics are necessary.
Michael Spiteller - One of the best experts on this subject based on the ideXlab platform.
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determination of antibiotics such as macrolides ionophores and tiamulin in Liquid Manure by hplc ms ms
Analytical and Bioanalytical Chemistry, 2003Co-Authors: Michael P Schlusener, Kai Bester, Michael SpitellerAbstract:A method for the analysis of several macrolide and ionophore antibiotics as well as tiamulin in Liquid Manure was developed. Reversed-phase Liquid chromatography and atmospheric pressure chemical ionisation (APCI) tandem mass spectrometry was used for detection.
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determination of selected sulfonamide antibiotics and trimethoprim in Manure by electrospray and atmospheric pressure chemical ionization tandem mass spectrometry
Rapid Communications in Mass Spectrometry, 2002Co-Authors: Thomas Pfeifer, Kai Bester, Jochen Tuerk, Michael SpitellerAbstract:A method for the determination of sulfonamides and trimethoprim in the complex matrix Liquid Manure has been developed using reversed-phase Liquid chromatography and atmospheric pressure chemical ionization (APCI) tandem mass spectrometry. A comparison was made between electrospray and atmospheric pressure chemical ionization. APCI proved to be more robust and less sensitive to matrix effects. High-performance Liquid chromatographic (HPLC) separation of the analytes was achieved in less than 7 min. The compounds were extracted with ethyl acetate and the extracts were cleaned up by solid-phase extraction on an aminopropyl column. Recoveries were not dependent on the concentration level. The mean recoveries were as follows: trimethoprim 79.0%, sulfadiazine 80.5%, N4-acetylsulfadiazine 91.0%, sulfamerazine 78.6%, sulfadimidine 77.2% and sulfamethoxazole 82.8%. Linearity was established over a concentration range of 5 to 5000 µg/kg with correlation coefficients greater than 0.99. The method had a limit of quantitation (LOQ) of 5 µg/kg Manure. Copyright © 2002 John Wiley & Sons, Ltd.
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Binding of Fluoroquinolone Carboxylic Acid Derivatives to Clay Minerals
Journal of Agricultural and Food Chemistry, 1997Co-Authors: Adrian Nowara, Jürgen Burhenne, Michael SpitellerAbstract:Large quantities of fluoroquinolone carboxylic acid (FQCA) derivatives are applied as antibacterial agents in large-scale animal husbandry. Important quantities are transported to agricultural areas by means of Liquid Manure. The binding of FQCA derivatives to clay minerals and their sorption by five soils from different geographic areas were investigated. Sorption was studied in batch experiments using radioactive labeled enrofloxacin (Baytril), decarboxylated enrofloxacin, ciprofloxacin (Cyprobay), levofloxacin (Oxaldin), and a fluorochloroquinolone carboxylic acid derivative. More than 90% (KD = 260−5612) of the applied enrofloxacin adsorbed on the different soils. The other chemicals showed a similar adsorption (KD = 285−496) on a German soil except the decarboxylated enrofloxacin (KD = 7.7). At clay minerals enrofloxacin was adsorbed >98%. X-ray diffraction analysis showed that the adsorption at the clay mineral montmorillonite occurred between the layers, resulting in an expansion of the spacing. Mi...
Silke Sczesny - One of the best experts on this subject based on the ideXlab platform.
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determination of persistent tetracycline residues in soil fertilized with Liquid Manure by high performance Liquid chromatography with electrospray ionization tandem mass spectrometry
Analytical Chemistry, 2002Co-Authors: Gerd Hamscher, Silke Sczesny, Heinrich HoperAbstract:Little is known about the occurrence and the fate of veterinary drugs in the environment. Therefore, a Liquid chromatography/tandem mass spectrometry method was developed and employed to investigate in detail the distribution and persistence of the frequently used tetracyclines and tylosin in a field fertilized with Liquid Manure on April 2000 and April 2001; soil sampling was performed in May 2000, November 2000, and May 2001. We detected 4.0 mg/kg tetracycline and 0.1 mg/kg chlortetracycline in the Liquid Manure of April 2000, as well as comparable amounts in the Liquid Manure of April 2001. In the soil samples of May 2001, the highest average concentrations of 86.2 (0−10 cm), 198.7 (10−20 cm), and 171.7 μg/kg (20−30 cm) tetracycline and 4.6−7.3 μg/kg chlortetracycline (all three sublayers) were found. At soil depths between 30 and 90 cm, as well as in soil or groundwater, tetracyclines could not be detected. In addition, oxytetracycline and tylosin could not be detected in any sample investigated. We c...
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determination of persistent tetracycline residues in soil fertilized with Liquid Manure by high performance Liquid chromatography with electrospray ionization tandem mass spectrometry
Analytical Chemistry, 2002Co-Authors: Gerd Hamscher, Silke Sczesny, Heinrich Hoper, Heinz NauAbstract:Little is known about the occurrence and the fate of veterinary drugs in the environment. Therefore, a Liquid chromatography/tandem mass spectrometry method was developed and employed to investigate in detail the distribution and persistence of the frequently used tetracyclines and tylosin in a field fertilized with Liquid Manure on April 2000 and April 2001; soil sampling was performed in May 2000, November 2000, and May 2001. We detected 4.0 mg/kg tetracycline and 0.1 mg/kg chlortetracycline in the Liquid Manure of April 2000, as well as comparable amounts in the Liquid Manure of April 2001. In the soil samples of May 2001, the highest average concentrations of 86.2 (0-10 cm), 198.7 (10-20 cm), and 171.7 microg/kg (20-30 cm) tetracycline and 4.6-7.3 micro/kg chlortetracycline (all three sublayers) were found. At soil depths between 30 and 90 cm, as well as in soil or groundwater, tetracyclines could not be detected. In addition, oxytetracycline and tylosin could not be detected in any sample investigated. We conclude that tetracyclines enter the environment in significant concentrations via repeated fertilizations with Liquid Manure, build up persistent residues, and accumulate in soil. Therefore, tetracyclines may have a potential risk and investigations on the environmental effects of these antibiotics are necessary.