排序方式: 共有71条查询结果,搜索用时 31 毫秒
61.
建立橙汁中4种链格孢霉毒素含量测定的凝胶渗透–超高效液相色谱–串联质谱检测方法。样品用乙腈提取后,用填料为Bio-Beads-S–X3的凝胶渗透色谱柱净化,净化时流动相采用乙酸乙酯–环己烷(体积比为1∶1),流速为5 mL/min,测定时用超高效液相反相C18色谱柱分离,甲醇–水系统梯度洗脱,采用电喷雾负离子源和多反应监测(MRM)模式定性和定量。4种链格孢霉毒素的最低定量限在0.0004~0.002 mg/kg范围内,加标回收率为78.9%~111.5%,测定结果的相对标准偏差均低于9.0%(n=10)。 相似文献
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《Journal of separation science》2018,41(3):756-764
An analytical method for the simultaneous determination of 13 mycotoxins in feed by magnetic dispersive solid‐phase extraction combined with ultra‐high performance liquid chromatography and tandem mass spectrometry was developed. The samples were extracted with acetonitrile/water (80:20, v/v, containing 3% acetic acid), and separated by centrifugation after salting‐out, and then treated with magnetic adsorbents to remove interferences. The separation of target mycotoxins was performed on an ACQUITY UPLC HSS T3 column using a mobile phase consisting of 1 mmol/L ammonium acetate with 0.1% formic acid and methanol by gradient elution. Good linearities for the 13 mycotoxins were achieved with correlation coefficients over 0.99, and the recoveries of mycotoxins were in the range of 89.3–112.6% at spiking at levels of 5, 20, and 100 μg/kg, with relative standard deviations of 0.9–10.4%. Based on the functional magnetic materials (MDN@Fe3O4, PSA@Fe3O4, ZrO2@Fe3O4) applied in dispersive solid‐phase extraction, the pretreatment process is more convenient and it is beneficial to reduce the experimental cost by reusing the recycled magnetic materials. It is a simple, rapid, and environmentally friendly analytical method for the determination of mycotoxins in feed. 相似文献
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Cover Picture: Biosynthesis of the Halogenated Mycotoxin Aspirochlorine in Koji Mold Involves a Cryptic Amino Acid Conversion (Angew. Chem. Int. Ed. 49/2014) 下载免费PDF全文
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Analytical methods for determination of mycotoxins: A review 总被引:10,自引:0,他引:10
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R. D. Voyksner W. M. Hagler K. Tyczkowska C. A. Haney 《Journal of separation science》1985,8(3):119-125
Thermospray high performance liquid chromatography/mass spectrometry (TSP HPLC/MS) was used to analyze five Fusarium mycotoxins in porcine plasma and urine. Four cytotoxic trichothecene mycotoxins, T-2 toxin, HT-2 toxin, diacetoxyscirpenol (DAS), deoxynivalenol (DON), T2 tetraol, and the fungal estrogen zearalenone (F-2 toxin) were analyzed. The thermospray mass spectrum contained molecular weight information with few, if any, fragment signals. Detection limits ranging from 1 to 10 ng of mycotoxin injected onto the HPLC column were obtained using selected ion monitoring (SIM) HPLC/MS. Neither the plasma nor the urine matrix interfered with TSP HPLC/MS analysis of these mycotoxins and no sample derivatization was necessary for the analysis. The TSP HPLC/MS technique appears to be ideal for very sensitive analysis of mycotoxins in biological samples. 相似文献
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Zougagh M Téllez H Sánchez A Chicharro M Ríos A 《Analytical and bioanalytical chemistry》2008,391(2):709-714
A procedure for the analytical validation of a rapid supercritical fluid extraction amperometric screening method for controlling
macrocyclic lactone mycotoxins in maize flour samples has been developed. The limit established by European legislation (0.2 mg
kg−1), in reference to zearalenone (ZON) mycotoxin, was taken as the reference threshold to validate the proposed method. Natural
ZON metabolites were also included in this study to characterize the final screening method. The objective was the reliable
classification of samples as positive or negative samples. The cut-off level was fixed at a global concentration of mycotoxins
of 0.17 mg kg−1. An expanded unreliability zone between 0.16 and 0.23 mg kg−1 characterized the screening method for classifying the samples. A set of 30 samples was used for the final demonstration
of the reliability and usefulness of the method. 相似文献
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被真菌毒素污染的食品可引发严重的健康问题,如癌症和畸形等,已成为全球公共卫生关注的焦点。因此,精准检测食品中痕量真菌毒素对保障人类健康具有重要意义。真菌毒素在食品中的浓度水平较低且易与复杂的食品基质成分结合,基质干扰严重影响检测的灵敏度,需采用有效的样品前处理技术进行富集和净化。固相萃取作为一种高效的样品前处理技术,其关键取决于萃取材料。该文总结了过去5年固相萃取材料在食品中真菌毒素样品前处理方面的研究进展,并对未来发展方向进行了展望,以期为食品中真菌毒素快速高效分析方法的开发提供参考。 相似文献
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Biosynthesis of the Halogenated Mycotoxin Aspirochlorine in Koji Mold Involves a Cryptic Amino Acid Conversion 下载免费PDF全文
Pranatchareeya Chankhamjon Dr. Daniela Boettger‐Schmidt Dr. Kirstin Scherlach Barbara Urbansky Dr. Gerald Lackner Daniel Kalb Hans‐Martin Dahse Prof. Dr. Dirk Hoffmeister Prof. Dr. Christian Hertweck 《Angewandte Chemie (International ed. in English)》2014,53(49):13409-13413
Aspirochlorine ( 1 ) is an epidithiodiketopiperazine (ETP) toxin produced from koji mold (Aspergillus oryzae), which has been used in the oriental cuisine for over two millennia. Considering its potential risk for food safety, we have elucidated the molecular basis of aspirochlorine biosynthesis. By a combination of genetic and chemical analyses we found the acl gene locus and identified the key role of AclH as a chlorinase. Stable isotope labeling, biotransformation, and mutational experiments, analysis of intermediates and an in vitro adenylation domain assay gave totally unexpected insights into the acl pathway: Instead of one Phe and one Gly, two Phe units are assembled by an iterative non‐ribosomal peptide synthetase (NRPS, AclP), followed by halogenation and an unprecedented Phe to Gly amino acid conversion. Biological assays showed that both amino acid transformations are required to confer cytotoxicity and antifungal activity to the mycotoxin. 相似文献