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Use of a new LC-MS method for the determination of pyrrolizidine alkaloids in feeds
2018
Kowalczyk, Ewelina | Kwiatek, Krzysztof
Pyrrolizidine alkaloids (PAs) are secondary metabolites produced by many plant species. Due to their toxicity PAs can pose a risk to human and animal health. To detect the toxic compounds in feed materials a sensitive method based on liquid chromatography coupled with mass spectrometry has been developed. PAs were extracted with sulphuric acid and purified with cation exchange cartridges. A newly developed solvent mixture consisting of ethyl acetate, methanol, acetonitrile, ammonia, and triethylamine was used to wash alkaloids from the cartridges. After evaporation the residues were reconstituted in water and methanol mixture and subjected to LC-MS analysis. The developed method was validated according to SANTE/11945/2015 guidelines. The recovery was from 84.1% to 112.9%, the repeatability ranged from 3.0% to 13.6%, and the reproducibility was from 4.8% to 18.9%. A sensitive and selective method for determination of PAs in feed materials has been developed and validated. All evaluated validation parameters were in accordance with EU Reference Laboratories document no. SANTE/11945/2015. Almost 41% of the analysed feed samples were positive for the presence of at least one PA.
显示更多 [+] 显示较少 [-]Pyrrolizidine alkaloids in honey: determination with liquid chromatography-mass spectrometry method
2018
Kowalczyk, Ewelina | Kwiatek, Krzysztof
Pyrrolizidine alkaloids (PAs) are probably the most widespread toxins of natural origin. More than 6,000 plant species produce these toxic compounds. Bees can forage on flowers of plants producing PAs, which leads to contamination of honey with the toxic compounds. To determine the contamination of honey with PAs, a sensitive method based on liquid chromatography coupled with mass spectrometry has been developed. PAs were extracted with 0.05 M sulphuric acid and purified with MCX cartridges. A solvent mixture consisting of ethyl acetate, methanol, acetonitrile, ammonia, and triethylamine (8:1:1:0.1:0.1, v/v) was used to wash alkaloids from the cartridges. After evaporation the residues were reconstituted in water and methanol mixture and subjected to LC–MS analysis. The developed method was validated according to SANTE/11945/2015 requirements. The recovery was from 80.6% to 114.5%. The repeatability ranged from 2.3% to 14.6%, and the reproducibility was from 4.9% to 17.7%. A new method for the determination of PAs in honey has been developed and validated. All evaluated parameters were in accordance with the SANTE/11945/2015 guidance document. Out of 50 analysed honey samples, 16 (32%) were positive for the content of at least one PA.
显示更多 [+] 显示较少 [-]Influence of applying effective microorganism (EM) in controlling ammonia and hydrogen sulphide from poultry manure
2018
Nurzillah M. | Norfadzrin F. | Haryani H.
Poultry layer houses are mostly open house system that generally faced with flies and odour and has become nuisance factors to society and the environment. This study was aimed to determine the effectiveness of applying EM in controlling pollutant gas emission at poultry layer house. A commercial poultry layer farmwas selected. Two treatments were carried out, the control without any application of microorganisms and the treated group with commercial microorganism application. Atmospheric ammonia and hydrogen sulphide were measured using a special instrument called ‘multi-gas detector’. The levels of ammonia and hydrogensulphide were measured twice a week. Odour production cannot be completely prevented on a farm. Therefore, most odour control methods are designed to keep or dissipate odours within the farm boundary, thus minimising odour complaints from surrounding neighbours. This paper reports that applying of effective microorganisms into the manure showed some positive influence in controlling atmospheric ammonia levels.
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