HPLC法测定谷类食品中的赭曲霉毒素A

目的:建立谷类食品中赭曲霉毒素A的HPLC检测方法。方法:样品经提取、过免疫亲和柱净化后,用高效液相色谱-荧光检测器进行分析。结果:赭曲霉毒素A在1~20 ng/m l范围内线性关系良好,r0.999。回收率在80%~110%之间,定量限为1μg/kg,检测限为0.3μg/kg。结论:该方法快速、简便、准确,可作为谷类食品中赭曲霉毒素A定量测定的有效手段。     

植物油中赭曲霉毒素和伏马毒素的污染调查分析

目的了解植物油中赭曲霉毒素(OTs)和伏马毒素(FBs)的污染状况。方法从超市采集植物油样品,利用液相色谱-串联质谱法,检测样品中的赭曲霉毒素和伏马毒素含量,并进行分析。结果 39份植物油样品中OTA污染最为严重(污染率为48.7%),OTB次之(33.3%),FB_1(15.4%)和FB_2(10.3%)检出较少,FB_3无检出。各毒素检出含量均低于国内安全限量,OTA最高检出水平(花生油样品)为0.36μg/kg,OTB最高检出水平(花生油样品)为0.28μg/kg。讨论目前植物油中赭曲霉毒素污染较其他毒素普遍,花生油污染水平相对高些,但总体上各毒素污染水平较低,不存在超标现象。     

用免疫学方法调查分析腊肉制品赭曲霉毒素A及其风险评估

目的:建立腊肉制品中赭曲霉毒素A免疫学检测的前处理方法,在对深圳市民膳食结构调查的基础上,对腊肉制品中的赭曲霉毒素污染进行了风险评估.方法:用免疫学方法检测40份市场腊肉制品.结果:从40份腊肉制品中检测9份含有OTA,平均污染程度为0.2768μg/kg.25份腊猪肉中有8份检出赭曲霉毒素A,污染程度在0～1.07 μg/kg;10份鸭肉中有1份检出赭曲霉毒素A,浓度为0.94 μg/kg;5份鸡肉均未检出赭曲霉毒素A.结论:本次检测的腊肉制品中,赭曲霉毒素A(OTA)含量最高的为1.07 oee'ks,表明市场上腊肉制品中OTA毒素污染水平不高,显示该产品风险较低.     

赭曲霉毒素A免疫学检测方法的研究

目的 建立敏感、特异和快速针对赭曲霉毒素A的酶联免疫吸附试验检测方法，研制具有我国自主知识产权的快速检测试剂盒。方法 利用B细胞杂交瘤技术，建立能够分泌抗赭曲霉毒素A单克隆抗体的杂交瘤细胞株，并获得抗赭曲霉毒素A单克隆抗体。结果 建立赭曲霉毒素A的间接竞争抑制性酶联免疫吸附试验测定方法(ELISA)。该方法的最低检出浓度为0.5ng/ml，线性范围2～500ng/ml，线性方程Y=0.272X 1.07(r=0.9978)。方法的加标回收率为79.0％～119.7％。利用该方法对北京市售的大米、小麦样品进行检测。结果表明．小麦样品的污染率为60.71％，最大值为8.26μg/kg；大米样品的污染率为17.86％，最大值为3.44μg/kg。结论 该方法简单、快速、灵敏。完全可以满足实际工作的需要。     

高效液相色谱法检测小麦、大米中赭曲霉毒素A

目的　建立赭曲霉毒素A的高效液相色谱检测方法 ;了解沈阳地区小麦、大米中赭曲霉毒素A的污染状况。方法　利用液 -液分离的前处理技术 ,选用C18反相柱 (2 5 0× 4 6mm) ,以乙腈∶0 0 0 8mol/L磷酸 =5 6∶44为流动相 ,流速 1ml/min荧光检测器 (激发波长 3 3 8nm ,发射波长 45 5nm) ,柱温 3 0℃。结果　实验所得回收率和精密度以及确证试验的结果均令人满意。结论　建立了用高效液相色谱法检测赭曲霉毒素A的方法 ,用本方法检测的 62份小麦、大米样品中 ,有 1份小麦样品为阳性 ,提示沈阳地区小麦和大米的赭曲霉毒素A污染率较低     

枸杞果酒中赭曲霉毒素A液相质谱串联法测定

目的 建立测定枸杞果酒中赭曲霉毒素A(OTA)的高效液相色谱-串联质谱法.方法 样品用免疫亲和柱净化,以Agilent Zorbax SB-C18色谱柱(2.1 mm×50 mm,3.5μm)分离;梯度洗脱流动相:水(含0.1％甲酸)和乙腈(含0.1％甲酸);流速:0.4 mL/min;进样量:10μL;电喷雾正离子多反应监测扫描模式(MRM)检测.结果 该方法的定量限为0.02 ng/mL,在0.02～ 20 ng/mL内线性关系良好,加样水平分别为0.2、2、20 ng/mL时,其回收率分别为71.0％、83.7％、86.0％,相对标准偏差(RSD)分别为8.0％、9.0％、6.1％;在随机购买的12份市售枸杞果酒中测得OTA的含量为0.03 ～0.18 ng/mL,检出率为50.0％.结论 赭曲霉毒素A在样品中的测定结果均低于欧盟限量;该方法简便、灵敏、准确,可应用于枸杞果酒中赭曲霉毒素A的测定.     

谷物和酒类中赭曲霉毒素A的测定

〔目的〕由于进出口食品、农产品可能污染赭曲霉毒素A,检验检疫机构为做好把关服务工作,需要筛选出快速、准确的定性定量的检测方法。〔方法〕对谷物和酒类中的赭曲霉毒素A,采用免疫亲和柱层析净化手段,进行荧光光度法和高效液相色谱法的测定。〔结果〕本方法在1～50μg/kg范围内的添加回收率为60.3%～118.9%,符合SN/T0005-1996的规定。〔结论〕方法快捷,能快速筛选、快速确证,符合准确检测的需要。     

赭曲霉群菌种产生赭曲霉毒素的调查研究

对赭曲霉群的各模式株和一些分离自我国的赭曲霉群菌株进行了赭曲霉毒素Ａ产生能力的检测，结果表明：产毒种不多，亦未检出强力产毒株。     

固相萃取-高效液相色谱检测啤酒中赭曲霉毒素A

目的建立一种啤酒中赭曲霉毒素A的分析检测方法.方法使用SPE-C18固相萃取,C18反相柱(250×4.6 mm)分离,乙腈-水-乙酸(99992)为流动相,荧光检测器(激发波长333 nm,发射波长460 nm)检测.结果啤酒不同水平的加标回收率为72.8%～87.0%,RSD均小于8.6%.并用该法测定了市售三种啤酒,均在检出限以下.赭曲霉毒素A标准溶液浓度0～200 ng/ml与峰面积呈良好线性关系,线性相关系数为0.9996.根据三倍噪声法.该法检出限为0.023 ng/ml.结论使用SPE-C18柱极大地简化了样品预处理手续,可建立一种简便、快速、准确、实用的啤酒中赭曲霉毒素A的分析方法.     

河北省食管癌、胃癌高发区居民食用小麦赭曲霉素A污染情况分析

目的探讨河北省食管癌、胃癌高发区居民食用小麦赭曲霉素A污染情况,了解居民的可能暴露量。方法深入高发区现场随机选取当地居民正在食用的小麦样品,利用反相-液相色谱法测定其赭曲霉素A含量。结果河北省胃癌高发区赞皇县居民食用小麦样品中赭曲霉素A的检出率为45.16%,平均含量2.41μg/kg,最高达14.25μg/kg。河北省磁县食管癌高发区居民食用小麦中赭曲霉素A的检出率为33.33%,平均含量0.59μg/kg,最高为1.63μg/kg。结论河北省胃癌食管癌高发区居民食用小麦赭曲霉素A的检出率明显高于国内其它地区的有关文献报道,应引起肿瘤防治工作者的重视。     

Determination of ochratoxin a in spices

The method of determination of ochratoxin A in some spices: coriander, cloves, ginger, paprika, black pepper was described. Depending on kind of matrix, extraction with metanol/water (80/20) or with solution of 1% NaHCO3 and several variants of clean-up on IAC columns were investigated. The most useful extraction solvent appeared water solution of 1% NaHCO3. In case of cloves only, none of the methods of extraction and clean-up variants was appropriate. The mean recovery of the method, dependent on kind of sample, was 61-82% and RSD% 1.4 and 7.8. The estimated LOD and LOQ were 0.02 and 0.06 microg/kg, respectively. In samples of spice used for method preparation, ochratoxin A was detected on the level 3.4-4.6 microg/kg.     

赭曲霉毒素A的酶联免疫吸附法检测

用酶联免疫吸附法检测食品等的真菌毒素的方法学研究进展很快。本文主要针对检测赭曲霉毒素Ａ的方法,包括抗原、抗体的制备方法及酶联免疫吸附法的进展做一综述性介绍。     

Determination of ochratoxin A by ELISA I. Study on the preparation of ochratoxin a antigen]

Ochratoxin A (OTA) antigen was prepared by activated ester method. Factors influencing OTA antigen were discussed and the optimum conditions was found by L9(3(4)) orthogonal design. The results showed that when the mole ratio was OTA:BSA = 20:1, OTA:NHS(N-hydroxy-succinamide):DCC(dicyclohexylcarbodiimide) = 1:2:4, the activate time was 120 min and the conjugation time was 90 min, the utilization of OTA could reach 48.2% and the best conjugation ratio of OTA and BSA was 9.64.     

赭曲霉毒素A的酶联免疫检测——Ⅰ.抗原的制备

采用活性酯法制备赭曲霉毒素A(OTA)的全抗原 ,并以正交试验L9(34 )来选择活性酯法的最佳条件。通过对实验结果的统计分析得出 ,当OTA与牛血清白蛋白 (BSA)的摩尔比为 2 0∶1,OTA∶N 羟基琥珀酰胺∶N’ ,N 二环乙基碳化亚胺的摩尔比为 1∶2∶4,OTA的活化时间为 6 0min ,偶联时间在 90min的情况下 ,OTA与BSA的连接比可达 9 6 4,OTA的利用率可达 48 2 %。     

Secretion of ochratoxin A in rabbit milk

The excretion of ochratoxin A in rabbit female was examined after a single intravenous administration of toxin. For the highest dose (4 mg par kg), the level in milk reached 1 ppm. The mammary excretion was also studied while plasma concentration of ochratoxin A was constant; the percentages of protein bound toxin in plasma and milk were determined. The likeness of theoretical and experimental ratio between mycotoxin levels in milk and plasma ultrafiltrates allowed to conclude in favour of the passage through the blood-milk barrier by nonionic passive diffusion of the free toxin. In conclusion, authors discussed about the sanitary problem concerning the presence of ochratoxin A in domestical animal milks.     

The effects of ochratoxin A on liver metabolism

This review summarizes the main toxic effect of ochratoxin A (OTA) on liver metabolism. This contaminant is a mycotoxin that can be found in raw materials (cereals, coffee, cocoa, spices or grapewine), in processed foods (bread and other bakery products) and, if animals are fed with contaminated feedstuffs, in pork meat. Kidney is a well-known target of OTA, although several findings suggest that liver metabolism can be affected too. OTA intake reduces, in a dose-dependent manner, the synthesis of albumin, while the concomitant increase in transaminases (ALT, ASP) and alkaline phosphatase is in agreement with the hypothesis of liver damage induced by OTA. Feeding animals with OTA-contaminated feeds has significant pro-oxidative effects that cause a reduction in anti-oxidative defences and an increase in malondialdehyde formation. Experiments on human liver cells support the hypothesis of an inflammatory effect of OTA mediated by TNF-??. An up-regulation of apoptosis has also been detected in hepatic cells after OTA treatment, which leads to a higher rate of cell death and to a reduction of liver activity. All these findings suggest that OTA can have a toxic effect on the liver too and for this reason we should pay attention to liver toxicity of OTA in the risk assessment for this mycotoxin.     

Biochemical changes in pig serum after ochratoxin A exposure

The objective of this study was to investigate the effect of ochratoxin A (OTA) on serum biochemical parameters of pigs during subchronic treatment with 300 μg OTA/kg of feed for 30 days. OTA treatment resulted in significantly higher (p < 0.05) serum levels of creatinine, urea, potassium and alkaline phosphatase, and significantly lower levels of glucose and total protein. These changes in serum biochemical parameters in treated pigs were indicative of impaired liver and kidney function caused by OTA exposure.