高效液相法同时检测谷物中玉米赤霉烯酮和赭曲霉毒素A

该研究开发一种快速、灵敏同时检测玉米、小麦和稻米中玉米赤霉烯酮(zearalenone,ZEN)和赭曲霉毒素A(ochratoxin A,OTA)的高效液相色谱检测方法。将样品采用乙腈/水(80/20,体积比),200 r/min,30℃振荡提取30 min后,经Oasis PRiME HLB固相萃取柱净化后,上样检测。该方法ZEN和OTA检测限(limit of detection,LOD)为3.7μg/kg和0.11μg/kg,定量限(quantification Limit,LOQ)为12.25μg/kg和0.38μg/kg,线性范围分别为10μg/kg^2000μg/kg和0.2μg/kg^200μg/kg,加标样品中不同浓度的ZEN和OTA回收率为83.0%~101.3%,日内精密度和日间精密度分别为3.12%~7.03%和3.57%~9.3%。该方法适用于玉米、小麦和稻米中ZEN和OTA的同时检测。     

Determination method of tricresyl phosphate in polyvinyl chloride

A simple and rapid method using HPLC was developed for the determination of tricresyl phosphate (TCP) in polyvinyl chloride (PVC) articles. A test sample was extracted with acetonitrile at 37 degrees C overnight. The extract solution diluted with an equivalent amount of water was applied to a Sep-Pak C18 cartridge, and TCP was eluted with acetonitrile-water (2:1) mixture. The eluate was analyzed by HPLC with an Inertsil Ph-3 column, using 65% acetonitrile/water as the mobile phase, with UV detection (264 nm). The calibration curve was rectilinear from 0.5 to 100 micrograms/mL. The recoveries of TCP added to various kinds of PVC articles at the level of 1,000 micrograms/g were 84.7-98.6%. The determination limit of TCP was 50 micrograms/g in samples. This method was applied to products including 3.1, 6.6 and 8.8% TCP and the recoveries of TCP were 87.3-91.4%. This method is very simple, and it seems suitable for a regulatory test.     

青稞真菌毒素检测分析

采集甘肃、西藏、青海、四川四省共299份青稞样品,采用高效液相色谱串联质谱方法对其13种真菌毒素进行检测分析.结果表明:4个省份青稞样品中13种真菌毒素均未超标,仅检出T-2毒素(T-2 Toxin)、玉米赤霉烯酮(Zearalenone,ZEN).青海部分地区T-2检出率为49.26％;四川部分地区T-2、ZEN,检...     

高效液相色谱法测定鸡组织中尼卡巴嗪标识残留物

应用高效液相色谱法测定鸡组织中尼卡巴嗪标识残留物-- 4,4＇- 二硝基均二苯脲。试样经乙腈-0.5g/mL氢氧化钾溶液提取,正己烷脱脂净化,用高效液相色谱仪(C18 柱)分析,流动相为乙腈- 体积分数1% 乙酸溶液(53:47,V/V),流速1.0mL/min,紫外检测波长为350nm。对鸡肉、鸡肝和鸡蛋样品进行0.05～0.50mg/kg 的药物添加回收实验,4,4＇- 二硝基均二苯脲的平均回收率为93.6%～102.0%(n=10),相对标准偏差为2.8%～10.4%,方法的定量限为0.05mg/kg。该法简便、准确,适用于鸡组织中尼卡巴嗪标识残留物4,4＇- 二硝基均二苯脲的检测。     

小豆内生真菌的筛选鉴定及其产玉米赤霉烯酮的可能性探究

玉米赤霉烯酮(zearalenone,ZEN)是目前全球范围污染谷物最广泛的霉菌毒素之一,对人体和动物健康都会产生极大威胁,目前从市售小豆检测到ZEN。【目的】筛选暴露ZEN的小豆内生真菌,结合经典方法和分子生物学方法鉴定所筛选内生真菌,并探索菌株潜在的ZEN产生风险。【方法】以暴露ZEN的小豆为样本,将分离纯化后的内生真菌进行经典形态观察;同时扩增真菌核糖体保守序列ITS1、ITS4,镰刀菌特异基因序列FU1、FU2确定小豆中镰刀菌种属,同时通过ZEN玉米赤霉烯酮产毒控制基因pks13进行PCR扩增,分析菌株ZEN合成的潜在风险。【结果】鉴别出3株镰刀菌,其中2株初步鉴定为砖红镰刀菌(Fusarium lateritium)、1株为花腐镰刀菌(Fusarium napiforme),未检测出ZEN合成关键基因;1株玛利节菱孢霉(Arthrinium marii),分子检测具有产ZEN玉米赤霉烯酮毒素的可能性。将以上4株菌分别回接至ZEN的产毒培养基,LC-MS/MS法未检测出ZEN毒素。【结论】暴露ZEN的小豆具有内生镰刀菌,存在可能产ZEN的内生节菱孢霉;回接培养基未检测到ZEN,但不排除小豆产生ZEN的风险。     

高效液相色谱法对玉米中玉米赤霉烯酮的测定

研究了高效液相色谱法测定玉米中玉米赤霉烯酮的方法.样品借鉴了GB/T 19540-2004中提取玉米赤霉烯酮的方法,通过Oasis HLB净化柱对提取液净化,以agilent extent C18色谱柱为分离柱,乙腈-水(V水:V乙腈=55:45)为流动相进行荧光检测(λex=235 nm,λem=460 nm).玉米赤霉烯酮的质量浓度在12～2 400μ/kg范围内呈良好线性,相关系数为0.9994,对添加高、中、低3个浓度玉米赤霉烯酮的玉米样品进行加标回收试验,平均回收率分别为96.736%、93.839%、86.240%,变异系数在1%～10%之间,最低检测限为10μ/kg.此方法对玉米中玉米赤霉烯酮的检测是可行的,且可给谷物中玉米赤霉烯酮检测方法优化提供参考.     

西藏酵母对玉米赤霉烯酮的清除效果及作用机理研究（网络首发、推荐阅读）

为研究清除粮食真菌毒素的绿色方法并克服生物法稳定性差的难题,以西藏酵母菌种为试验对象,筛选对玉米赤霉烯酮（Zearalenone,ZEN）具有较好清除效果的菌种,并研究其作用机理。结果表明：西藏胶红酵母对ZEN具有较好的降解效果,且随菌液浓度的升高其降解效果逐步提高;对酵母不同处理液的毒素清除效果评价,发现该酵母对ZEN的清除机理主要为吸附作用,同时伴有一定的胞内生物降解作用;采用液质联用对ZEN的降解产物进行测定,发现其降解产物可能为玉米赤霉烯醇和玉米赤霉酮,降解产物的安全性需进一步验证;经西藏胶红酵母的胁迫耐受试验,表明具有一定的低温和氧化胁迫耐受能力。     

高效液相色谱法同时检测粮食中常见8 种真菌毒素的含量

建立免疫亲和柱净化-高效液相色谱法同时测定粮食中黄曲霉毒素B1（aflatoxins,AFB1）、黄曲霉毒素B2（AFB2）、黄曲霉毒素G1（AFG1）、黄曲霉毒素G2（AFG2）、赭曲霉毒素A（ochratoxin A,OTA）、玉米赤霉烯酮（zearalenone,ZEN）、呕吐毒素（deoxynivalenol,DON）和T-2毒素的检测方法。样品经乙腈-水提取后,用免疫亲和柱净化,Agilent Elipse Plus C18（100 mm×4 mm,3.5 μm）色谱柱分离,以甲醇-乙腈-水-乙酸为流动相,流速1 mL/min,柱温35 ℃,进样量20 μL,检测系统为可变波长检测器串联光化学衍生器串联荧光检测器。根据信噪比为3的峰响应值,确定各真菌毒素的检出限为：AFB1 0.446 ng/mL、AFB2 0.152 ng/mL、AFG1 0.523 ng/mL、AFG2 0.334 ng/mL、ZEN 7 ng/mL、OTA 0.7 ng/mL、DON 200 ng/mL、T-2毒素100 ng/mL。样品中各真菌毒素的平均加标回收率,玉米为80.0%～104.5%,小麦为83.2%～102.8%,方法精密度为2.6%～10.2%。从样品前处理到分析整个过程耗时约2 h。本方法简便、快速、灵敏度高,适用于粮食中多种真菌毒素的快速测定。     

LC-MS/MS multi-method for mycotoxins after single extraction, with validation data for peanut, pistachio, wheat, maize, cornflakes, raisins and figs

Mycotoxin analysis is usually carried out by high performance liquid chromatography after immunoaffinity column cleanup or in enzyme-linked immunosorbent assay tests. These methods normally involve determination of single compounds only. EU legislation already exists for the aflatoxins, ochratoxin A and patulin in food, and legislation will come into force for deoxynivalenol, zearalenone and the fumonisins in 2007. To enforce the various legal limits, it would be preferable to determine all mycotoxins by routine analysis in different types of matrices in one single extract. This would also be advantageous for HACCP control purposes. For this reason, a multi-method was developed with which 33 mycotoxins in various products could be analysed simultaneously. The mycotoxins were extracted with an acetonitrile/water mixture, diluted with water and then directly injected into a LC-MS/MS system. The mycotoxins were separated by reversed-phase HPLC and detected using an electrospray ionisation interface (ESI) and tandem MS, using MRM in the positive ion mode, to increase specificity for quality control. The following mycotoxins could be analysed in a single 30-min run: Aflatoxins B1, B2, G1 and G2, ochratoxin A, deoxynivalenol, zearalenone, T-2 toxin, HT-2 toxin, alpha-zearalenol, alpha-zearalanol, beta-zearalanol, sterigmatocystin, cyclopiazonic acid, penicillic acid, fumonisins B1, B2 and B3, diacetoxyscirpenol, 3- and 15-acetyl-deoxynivalenol, zearalanone, ergotamin, ergocornin, ergocristin, alpha-ergocryptin, citrinin, roquefortin C, fusarenone X, nivalenol, mycophenolic acid, alternariol and alternariol monomethyl ether. The limit of quantification for the aflatoxins and ochratoxin A was 1.0 microg kg(-1) and for deoxynivalenol 50 microg kg(-1). The quantification limits for the other mycotoxins were in the range 10-200 microg kg(-1). The matrix effect and validation data are presented for between 13 and 24 mycotoxins in peanuts, pistachios, wheat, maize, cornflakes, raisins and figs. The method has been compared with the official EU method for the determination of aflatoxins in food and relevant FAPAS rounds. The multi-mycotoxin method has been proven by the detection of more than one mycotoxin in maize, buckwheat, figs and nuts. The LC-MS/MS technique has also been applied to baby food, which is subject to lower limits for aflatoxin B1 and ochratoxin A, ergot alkaloids in naturally contaminated rye and freeze-dried silage samples.     

Stability of zearalenone during extrusion of corn grits

The effects of extrusion cooking on the stability of zearalenone (ZEN) in spiked (4.4 microg/g) food-grade corn grits were investigated using a twin screw extruder. A ground rice culture material containing a high level of ZEN was used to spike the corn grits. The extrusion variables were screw type (mixing and nonmixing), temperature (120, 140, and 160 degrees C), and moisture content (18, 22, and 26%). Both unextruded and extruded samples were analyzed for ZEN by high-performance liquid chromatography. Extrusion cooking of the corn grits resulted in significant reductions of ZEN in grits extruded with either mixing screws or nonmixing screws, but use of mixing screws was somewhat more effective (66 to 83%) overall than nonmixing screws (65 to 77%). Greater reduction of ZEN was observed at either 120 or 140 degrees C than at 160 degrees C. The moisture content of corn grits was not a significant factor affecting reduction of ZEN during extrusion with either mixing or nonmixing screws.     

河北地区面制品中脱氧雪腐镰刀菌烯醇及其衍生物和玉米赤霉烯酮污染水平调查与分析

目的了解河北地区面制品中脱氧雪腐镰刀菌烯醇(deoxynivalenol,DON)及其衍生物3-ADON、15-ADON和玉米赤霉烯酮(zearalenone,ZEN)污染状况。方法对河北地区79份烘烤食品(饼干、面包)、87份生面制品和89份馒头样品进行调查分析。样品经乙腈:水(84:16, V:V)溶液超声离心提取后,通过多功能固相萃取柱进行净化处理,采用高效液相色谱-串联质谱法进行检测。结果 255份样品中,3A-DON、15A-DON和ZEN检出率均不高;DON检出率较高,共检出阳性样品252份,检出率为98.8%,超标样品10份,超标率为3.9%。4种真菌毒素污染较为严重的样品为饼干样品,其检出率和超标率明显高于其他面制品。结论在面制品中,主要的污染物为DON,污染最严重的样品类别为饼干样品,其污染状况应引起关注。     

LC-MS/MS multi-method for mycotoxins after single extraction, with validation data for peanut, pistachio, wheat, maize, cornflakes, raisins and figs.

Mycotoxin analysis is usually carried out by high performance liquid chromatography after immunoaffinity column cleanup or in enzyme-linked immunosorbent assay tests. These methods normally involve determination of single compounds only. EU legislation already exists for the aflatoxins, ochratoxin A and patulin in food, and legislation will come into force for deoxynivalenol, zearalenone and the fumonisins in 2007. To enforce the various legal limits, it would be preferable to determine all mycotoxins by routine analysis in different types of matrices in one single extract. This would also be advantageous for HACCP control purposes. For this reason, a multi-method was developed with which 33 mycotoxins in various products could be analysed simultaneously. The mycotoxins were extracted with an acetonitrile/water mixture, diluted with water and then directly injected into a LC-MS/MS system. The mycotoxins were separated by reversed-phase HPLC and detected using an electrospray ionisation interface (ESI) and tandem MS, using MRM in the positive ion mode, to increase specificity for quality control. The following mycotoxins could be analysed in a single 30-min run: Aflatoxins B1, B2, G1 and G2, ochratoxin A, deoxynivalenol, zearalenone, T-2 toxin, HT-2 toxin, alpha-zearalenol, alpha-zearalanol, beta-zearalanol, sterigmatocystin, cyclopiazonic acid, penicillic acid, fumonisins B1, B2 and B3, diacetoxyscirpenol, 3- and 15-acetyl-deoxynivalenol, zearalanone, ergotamin, ergocornin, ergocristin, alpha-ergocryptin, citrinin, roquefortin C, fusarenone X, nivalenol, mycophenolic acid, alternariol and alternariol monomethyl ether. The limit of quantification for the aflatoxins and ochratoxin A was 1.0 microg kg(-1) and for deoxynivalenol 50 microg kg(-1). The quantification limits for the other mycotoxins were in the range 10-200 microg kg(-1). The matrix effect and validation data are presented for between 13 and 24 mycotoxins in peanuts, pistachios, wheat, maize, cornflakes, raisins and figs. The method has been compared with the official EU method for the determination of aflatoxins in food and relevant FAPAS rounds. The multi-mycotoxin method has been proven by the detection of more than one mycotoxin in maize, buckwheat, figs and nuts. The LC-MS/MS technique has also been applied to baby food, which is subject to lower limits for aflatoxin B1 and ochratoxin A, ergot alkaloids in naturally contaminated rye and freeze-dried silage samples.     

ANTIOXIDANT ACTIVITY OF GREEN TEA CATECHINS IN A β-CAROTENE-LINOLEATE MODEL SYSTEM

A crude mixture of catechins was isolated from Chinese green tea leaves using a hot water extraction. Individual catechins were then separated by chromatographic means using Sephadex LH-20 followed by semi-preparative HPLC. The antioxidant activity of crude and individual catechins was then determined in a β-carotene-linoleate model system. Results indicated that (−)-epicatechin-3-gallate (ECG) possessed the strongest antioxidative activity and (−)-epigallocatechin (EGC) showed the weakest effect. The antioxidative efficacy of (−)-epicatechin (EC) and (−)-epigallocatechin-3-gallate (EGCG) was similar and in between those of ECG and EGC. Furthermore, the antioxidant activity of a reconstituted catechin mixture in the proportions present in the crude extract was lower than that of the crude mixture itself, thus indicating that noncatechin components in the mixture possessed their own antioxidant activity or acted synergistically with the catechins.     

Rapid purification method for fumonisin B1 using centrifugal partition chromatography

Fumonisin B1 (FB1) is a highly toxic mycotoxin produced by fungal strains belonging to the Fusarium genus, which can be found mainly in maize products, and is gaining interest in food safety. To produce large amounts of pure FB1, a novel purifying method was developed by using centrifugal partition chromatography, which is a prominent member of the liquid–liquid chromatographic techniques. Rice cultured with Fusarium verticillioides was extracted with a mixture of methanol/water and found to contain 0.87?mg of FB1 per gram. The crude extracts were purified on a strong anion-exchange column and then separated by using a biphasic solvent system consisting of methyl-tert-butyl-ether–acetonitrile–0.1% formic acid in water. The collected fractions were analysed by flow injection–mass spectrometry and high-performance liquid chromatography coupled with Corona-charged aerosol detector and identified by congruent retention time on high-performance liquid chromatography and mass spectrometric data. This method produced approximately 120?mg of FB1 with a purity of more than 98% from 200?g of the rice culture. The whole purification process is able to produce a large amount of pure FB1 for analytical applications or for toxicological studies.     

黑米花色苷的提取及纯化

目的：得到黑米花色苷最佳提取工艺,建立应用大孔吸附树脂纯化花色苷的方法。方法：以矢车菊素-3- 葡萄糖苷为跟踪指标,通过单因素试验和正交试验,对影响黑米花色苷提取的各因素进行研究,比较9 种大孔吸附树脂对花色苷的静态吸附和解吸性能。结果：黑米花色苷最佳提取条件,提取液乙醇- 水- 盐酸体积比为50:50:0.5,温度50℃,固液比为1:10(g/mL),提取时间为1h,提取次数为3 次。通过对9 种大孔吸附树脂的比较,确定AB-8 为纯化黑米的理想吸附树脂,80% 乙醇为洗脱剂,上样流速为1.0BV/h,解吸流速为2.0BV/h。结论：测定经树脂纯化后提取物中花色苷的含量达到22.59%(粗提物中花色苷含量为3.448%),树脂富集倍数为 6.02,此工艺条件纯化效果显著。     

利用噬菌体肽库淘选玉米赤霉烯酮的模拟表位

目的:利用噬菌体肽库淘选玉米赤霉烯酮(zearalenone,ZEN)模拟表位。方法:以抗ZEN单克隆抗体为配体,利用噬菌体七肽库淘选ZEN的模拟表位,采用了逐轮减少抗体包被浓度,交换使用封阻液中蛋白质种类的方法,经三轮淘选后,随机挑取20个克隆测序并以ELISA方法及竞争ELISA实验,以确定阳性克隆。结果:获得10种序列,ELISA显示其中两种序列为阳性克隆,抑制率达90%以上,其氨基酸序列分别为DAVILLM,HHCHWWH。结论:噬菌体展示技术可淘选到ZEN的模拟表位,淘选到的噬菌体粒子可作为毒素的替代品建立免疫学检测方法。     

橘霉素免疫牛蛙肌肉蛋白柱的制备及其吸附橘霉素作用分析

用橘霉素人工抗原-佐剂免疫牛蛙,研究牛蛙肌肉蛋白质对橘霉素结合能力的大小。将能与橘霉素结合的蛋白质用海藻酸钠制粒。取6.4?mg橘霉素人工抗原免疫牛蛙肌肉蛋白质,使用海藻酸钠质量浓度4?g/100?mL、氯化钙质量浓度5?g/100?mL、戊二醛交联体积分数0.2%、交联时间2?h,制备海藻酸钙包埋蛋白质凝胶微球。取海藻酸钙凝胶微球2?g装填成固相小柱,以2?mL红曲米橘霉素提取液过柱,以20?mL超纯水洗脱杂质,与市售免疫亲和柱色谱图比较,均没有杂质干扰峰。以橘霉素标准液作为上样液,以70%乙腈-三氟乙酸作为橘霉素洗脱液,洗脱剂量为5?mL,回收率为86.7%,柱容量为0.101?μg/g。采用自制的牛蛙免疫蛋白柱和市售免疫亲和柱测得红曲米中橘霉素含量分别为0.037?μg/g和0.043?μg/g。     

Simple and high-throughput method for the multimycotoxin analysis in cereals and related foods by ultra-high performance liquid chromatography/tandem mass spectrometry

A rapid, reliable and sensitive method was developed to determine 12 mycotoxins (deoxynivalenol, aflatoxins B1, B2, G1, G2 and M1, fumonisins B1 and B2, ochratoxin A, HT-2 and T-2 toxin and zearalenone) simultaneously in maize, walnuts, biscuits and breakfast cereals. The method is based on a single extraction step using acetonitrile/water mixture (80/20 v/v) followed by ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC–MS/MS). The selectivity of the MS/MS detection allowed the elimination of further clean up steps. Extraction, chromatographic and detection conditions were optimised in order to increase sample throughput and sensitivity. Matrix-matched calibration was used for quantification and recoveries of the extraction process ranged from 70.0% and 108.4%, with relative standard deviations lower than 25% in all the cases, when samples were fortified at 5 and 50 μg/kg. Limits of detection ranged from 0.01 to 2.1 μg/kg and limits of quantification ranged from 0.03 to 6.30 μg/kg, which were always below the tolerance levels of mycotoxins set by European Union in the matrices evaluated. Several samples were analysed and aflatoxins B1, B2, G1, G2 and T-2 toxin were detected in one maize sample, with concentrations lower than 6.0 μg/kg and deoxynivalenol was detected in a breakfast cereal at 42.1 μg/kg.     

LC–MS/MS multi-method for mycotoxins after single extraction,with validation data for peanut,pistachio, wheat,maize, cornflakes,raisins and figs

Mycotoxin analysis is usually carried out by high performance liquid chromatography after immunoaffinity column cleanup or in enzyme-linked immunosorbent assay tests. These methods normally involve determination of single compounds only. EU legislation already exists for the aflatoxins, ochratoxin A and patulin in food, and legislation will come into force for deoxynivalenol, zearalenone and the fumonisins in 2007. To enforce the various legal limits, it would be preferable to determine all mycotoxins by routine analysis in different types of matrices in one single extract. This would also be advantageous for HACCP control purposes. For this reason, a multi-method was developed with which 33 mycotoxins in various products could be analysed simultaneously. The mycotoxins were extracted with an acetonitrile/water mixture, diluted with water and then directly injected into a LC–MS/MS system. The mycotoxins were separated by reversed-phase HPLC and detected using an electrospray ionisation interface (ESI) and tandem MS, using MRM in the positive ion mode, to increase specificity for quality control. The following mycotoxins could be analysed in a single 30-min run: Aflatoxins B₁, B₂, G₁ and G₂, ochratoxin A, deoxynivalenol, zearalenone, T-2 toxin, HT-2 toxin, α-zearalenol, α-zearalanol, β-zearalanol, sterigmatocystin, cyclopiazonic acid, penicillic acid, fumonisins B₁, B₂ and B₃, diacetoxyscirpenol, 3- and 15-acetyl-deoxynivalenol, zearalanone, ergotamin, ergocornin, ergocristin, α-ergocryptin, citrinin, roquefortin C, fusarenone X, nivalenol, mycophenolic acid, alternariol and alternariol monomethyl ether. The limit of quantification for the aflatoxins and ochratoxin A was 1.0 µg kg^?1 and for deoxynivalenol 50 µg kg^?1. The quantification limits for the other mycotoxins were in the range 10–200 µg kg^?1. The matrix effect and validation data are presented for between 13 and 24 mycotoxins in peanuts, pistachios, wheat, maize, cornflakes, raisins and figs. The method has been compared with the official EU method for the determination of aflatoxins in food and relevant FAPAS rounds. The multi-mycotoxin method has been proven by the detection of more than one mycotoxin in maize, buckwheat, figs and nuts. The LC–MS/MS technique has also been applied to baby food, which is subject to lower limits for aflatoxin B₁ and ochratoxin A, ergot alkaloids in naturally contaminated rye and freeze-dried silage samples.     

Zearalenone contamination in corn for human consumption in the state of Tlaxcala,Mexico

Corn from various regions of the state of Tlaxcala, Mexico was sampled to determine whether or not corn which is consumed by humans is contaminated with the estrogenic mycotoxin zearalenone (ZEA). In order to quantify this mycotoxin, a method with adequate sensitivity using solid–liquid extraction and high-performance liquid chromatography (HPLC) with UV diode array detection was optimized. ZEA and zearalanol, used as an internal standard, were extracted from 5 g of a finely ground corn sample with an 85:15 v/v methanol:water solution, cleaned by way of a Florisil column, defatted with n-hexane, and subsequently re-extracted with chloroform. The separation was performed on a reverse phase analytical column. Detection was confirmed by on-line simultaneous UV spectral scanning during the chromatographic run. The method’s limit of detection was 0.7 ng/g and the recovery average was 90%. Analysis of 24 samples indicates that approximately 70% of the monitored samples were contaminated with zearalenone, with levels ranging from 3 to 83 μg/kg of corn kernels.