超高效液相色谱-串联质谱法检测小米及面粉中4种镰刀菌毒素

目的建立小米及面粉中脱氧雪腐镰刀菌烯醇(deoxynivalenol,DON)、3-乙酰脱氧雪腐镰刀菌烯醇(3-acetyl deoxidized snow-scylienol,3-AC-DON)、15-乙酰脱氧雪腐镰刀菌烯醇(15-acetyl deoxidized snow-scyloxanol,15-AC-DON)和玉米赤霉烯酮(zearalenone,ZEN)的超高效液相色谱-串联三重四极杆质谱测定方法。方法经乙腈-水(84:16,V:V)提取样品,通过多功能净化柱净化,以BEH C_(18)柱(2.1 mm×100 mm,1.7μm)分离,流动相为0.2%氨水:乙腈梯度洗脱,电喷雾离子(multiple reaction monitoring,MRM)模式检测。结果玉米赤霉烯酮检出限为0.1μg/kg,定量限为0.3μg/kg,线性范围为2.0～30.0μg/L;脱氧雪腐镰刀菌烯醇及其衍生物的检出限为0.2μg/kg,定量限为0.6μg/kg,线性范围为10.0～150.0μg/L。加标回收率88.9%～106.0%。结论本方法快速、准确、灵敏度高,能满足4种镰刀菌毒素的同时检测。     

固相萃取柱净化-液相色谱-串联质谱法测定糕点中脱氧雪腐镰刀菌烯醇及其衍生物和玉米赤霉烯酮

建立使用超高效液相色谱-串联质谱仪测定糕点中玉米赤霉烯酮(ZEN)、脱氧雪腐镰刀菌烯醇(DON)及其衍生物3-乙酰基-脱氧雪腐镰刀菌烯醇(3-Ac DON)、15-乙酰基-脱氧雪腐镰刀菌烯醇(15-Ac DON)4种真菌毒素的方法。该方法在4 min内完成4种真菌毒素的分析,线性范围5~1000μg/kg,标准曲线的相关系数均在0.997以上,DON、ZEN的最低检出限为1.0μg/kg,3-Ac DON、15-Ac DON的最低检出限为1.5μg/kg。通过对134份市售预包装糕点样品进行分析发现,4种真菌毒素均有一定检出,其中ZEN、DON、3-Ac DON和15-Ac DON的检出率分别为2.2%、78.4%、3.0%和5.2%,所有样品中4种真菌毒素含量水平均未超过食品安全国家标准限量要求。     

免疫亲和柱净化—高效液相色谱法同时检测小麦中脱氧雪腐镰刀菌烯醇及其衍生物

建立脱氧雪腐镰刀菌烯醇(DON)及其衍生物3-乙酰基—脱氧雪腐镰刀菌烯醇(3-ADON)和15-乙酰基—脱氧雪腐镰刀菌烯醇(15-A-DON)的免疫亲和柱净化—高效液相色谱同时检测方法。小麦样品经超纯水提取、免疫亲和柱净化、吹干、定容后,用配有紫外检测器的高效液相色谱仪进行DON、3-A-DON和15-A-DON三种毒素的同时检测,并与液相色谱质谱法比对。结果表明:该方法检出限,DON、3-A-DON和15-A-DON均为100μg/kg,样品加标回收率范围86.6%~96.5%,变异系数小于10%,具有较好的准确性和精密度。该方法简单、快速、灵敏度高、选择性好,适用于小麦中DON、3-A-DON和15-A-DON的同时检测。     

谷物及其制品中脱氧雪腐镰刀菌烯醇及其衍生物的检测及污染规律分析

采用高效液相色谱-质谱联用技术建立测定小麦粉、挂面、玉米糁、大米等谷物及其制品中脱氧雪腐镰刀菌烯醇(deoxynivalenol,DON)、脱氧雪腐镰刀菌烯醇-3-葡萄糖苷(deoxynivalenol-3-glucoside,D3G)、3-乙酰基脱氧雪腐镰刀菌烯醇(3-acetyldeoxynivalenol,3ADON)及15-乙酰基脱氧雪腐镰刀菌烯醇(15-acetyldeoxynivalenol,15ADON)的检测方法,并对各种粮食中的污染情况进行调查。样品采用乙腈提取,正己烷除脂和固相萃取柱净化后,采用高效液相色谱-串联质谱检测,外标法定量。方法均经过优化和验证,满足谷物及其制品的检测要求。分析96份谷物及其制品中4种真菌毒素的污染规律,结果表明,15ADON无检出,只有1个样品检出3ADON,DON和D3G均有不同程度的检出,DON检出率大于D3G,其中在挂面中的含量最高。D3G与DON的含量呈正相关,D3G/DON在30%左右,且不同谷物种类主要污染的毒素种类均以DON为主,其中挂面的污染最为严重。     

脱氧雪腐镰刀烯醇（呕吐毒素）酶标抗原的合成及免疫抗体的制备

利用琥珀酸酐法合成了脱氧雪腐镰刀烯醇-琥珀酸酐衍生物(3-HS-DON),并用DCC法将该衍生物与牛血清白蛋白(BSA)偶联得到的结合物(DON-HS-BSA)作为免疫抗原免疫新西兰大白兔,获得效价为1∶10000的特异性抗脱氧雪腐镰刀烯醇(DON)的抗体。同时,用EDC法将3-HS-DON与辣根过氧化物酶(HRP)偶联得到酶标抗原(DON-HS-HRP)。通过圆二色光谱(CD)看到偶联后蛋白二级结构发生了改变,酶活稍有下降;用分光光度法测得酶标抗原酶活损失<5%,偶联物中DON与HRP的结合比为5.29。说明:该酶偶联物及制备的抗体可作为酶联免疫吸附法(ELISA)或免疫传感器法测试脱氧雪腐镰刀烯醇时所需的酶标抗原及抗体。     

脱氧雪腐镰刀菌烯醇胶体金检测试纸的研制及应用

采用合成脱氧雪腐镰刀菌烯醇(Dexynivalenol,DON)人工抗原,制备抗脱氧雪腐镰刀菌烯醇单克隆抗体(mAb),并以此为基础建立胶体金免疫层析检测试纸,于胶体金读数仪配合使用,用于进行玉米和小麦样品中DON的快速定量检测。通过检测玉米和小麦样品,脱氧雪腐镰刀菌烯醇胶体金试纸方法检测限为87μg/kg,定量限为290μg/kg,线性范围400~5 000μg/kg,相关系数r=0.998。以国家标准(GB/T23503—2009)免疫亲和柱-高效液相色谱法检测样品的结果为认定值,胶体金检测法的准确度在80.7%~143.6%,变异系数范围4.7%~16.4%。采用配对t-检验分析,胶体金检测法与国标液相方法无显著性差异。     

免疫亲和柱净化结合高效液相色谱法测定小麦粉中的脱氧雪腐镰刀菌烯醇

使用小麦粉中脱氧雪腐镰刀菌烯醇(Deoxynivalenol,DON)免疫亲和柱结合高效液相色谱法(HPLC)测定方法。使用该方法简便、快速、灵敏度高,能准确检测出小麦粉中雪腐镰刀菌烯醇含量。经水提取后,采用免疫亲和柱净化,通过高效液相色谱-紫外检测器测定,检测小麦粉中脱氧雪腐镰刀菌烯醇的含量,根据峰面积定量。实践研究显示:小麦粉中的脱氧雪腐镰刀菌烯醇经水提取,免疫亲和柱净化后检测线性较好,相关系数大于等于0.999,定量限为16μg/kg,脱氧雪腐镰刀菌烯醇加标回收率为90.6%,RSD为2.1%。     

小麦籽粒中原型及修饰型脱氧雪腐镰刀菌烯醇的产生规律研究

目的研究原型脱氧雪腐镰刀菌烯醇(deoxynivalenol, DON)及其修饰型的产生规律。方法以小麦籽粒为培养材料,辐照灭菌后接种禾谷镰刀菌,并分别在不同温度(10、20、30℃)和水活度(0.95、0.98 a_w)下培养不同时间(7、14、21、28、35d)后,运用超高效液相色谱-串联质谱检测DON,3-乙酰化脱氧雪腐镰刀菌烯醇(3-acetyl-deoxynivalenol,3-ADON),15-乙酰化脱氧雪腐镰刀菌烯醇(15-acetyl-deoxynivalenol,15-ADON)和脱氧雪腐镰刀菌烯醇-3-葡萄糖苷(deoxynivalenol-3-glucoside,D3G)的产量。结果在所有培养条件下,原型DON的产量均随时间延长而增加;并于0.98 a_w, 20℃下的第35 d达到最高值100490.0μg/kg;不同培养条件下,修饰型DON的生成情况各不相同,3-ADON、15-ADON和D3G分别于0.98a_w,20℃下的第14、28和35 d达到各自产量最高值(3-ADON:7583.5μg/kg; 15-ADON:592.0μg/kg; D3G:6806.4μg/kg)。此外, 10℃下,D3G/DON比值随时间延长先增高后降低,而20、30℃下D3G/DON比值随时间延长呈指数下降(r~20.90)。结论小麦籽粒中原型和修饰型DON的最适产生条件均为0.98 a_w, 20℃。本研究可为DON及其修饰型的生物合成、日常监管、污染防控等提供理论基础和科学依据。     

超高液相色谱串联质谱法测定小麦粉中真菌毒素

建立小麦粉中雪腐镰刀菌烯醇(NIV)、隐蔽型脱氧雪腐镰刀烯醇(Deepoxy-DON)、脱氧雪腐镰刀菌烯醇(DON)及衍生物(3A-DON、15A-DON)、玉米赤霉烯酮(ZEN)常见6种真菌毒素的同时测定方法。试样用多功能净化柱净化,液相色谱-串联质谱基质内标法定量测定。结果表明6种真菌毒素的检出限在0.50μg/kg~1.00μg/kg之间,线性相关系数R~20.994,3个水平加标回收率为82.1%~108.9%,RSD为4.6%~14.5%。采用本方法参加面粉中脱氧雪腐镰刀烯醇能力验证样品质控考核,统计结果 Z为-1.93,结果评价为满意。该方法准确、灵敏、高效,可适用于小麦粉中6种常见真菌毒素的定量分析。     

粮食真菌DNA快速高通量提取方法的建立与应用

目的 建立一种高效、快速、高通量的粮食中真菌DNA提取和分析方法,并应用于小麦产脱氧雪腐镰刀菌烯醇(deoxynivalenol, DON)镰刀菌污染状况研究。方法 基于磁珠纯化技术,开发了一种粮食基质中真菌DNA的快速提取方法—月桂酰肌氨酸钠(sodium lauroyl sarcosine, SLS)磁珠法,结合前期采用实时荧光定量PCR法(quantitative real-time PCR, qPCR)和微滴式数字PCR法(droplet digital PCR, ddPCR)建立的小麦中3-乙酰基脱氧雪腐镰刀菌烯醇(3-acetyldeoxynivalenol, 3-ADON)和15-乙酰基脱氧雪腐镰刀菌烯醇(15-acetyldeoxynivalenol, 15-ADON)两种产DON毒素化学型镰刀菌及禾谷镰刀菌复合群分析方法,对其提取效果进行了验证并分析了我国2021年新收获小麦产DON镰刀菌的污染水平。结果 与十六烷基三甲基溴化铵(cetyl trimethyl ammonium bromide,CTAB)法、柱式法试剂盒和磁珠法试剂盒相比较,本研究建立的SLS磁珠法裂解过程无需水浴,配合自动化提取设备工作,整个提取时间小于1 h,对禾谷镰刀菌复合群的提取率最优,而对3-ADON和15-ADON化学型镰刀菌的提取率与经典CTAB法、磁珠法试剂盒没有显著性差异,并且显著性优于柱式法试剂盒。在对2021年收获的120个小麦样品监测结果显示,产DON镰刀菌的生物量与DON毒素水平之间具有极显著的相关性(P<0.01)。结论 SLS磁珠法适用于从基质复杂的粮食样品中提取真菌DNA,操作简便快速、提取率高,更易实现大样本量的分子生物学准确定量检测需求。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

Influence des ions sur le pouvoir hydratant de l'ure e: e tude sur peau de porc ex vivo

This study deals with the influence of ions (NaCl and MgSO4) in a W/O emulsion containing 10% urea. Moisturization kinetics are assessed by corneometry on pig skin ex vivo. The formula's influence on urea penetration is measured by infrared spectrometry with an ATR device and the stripping method. Corneometry and spectroscopy were chosen to record simultaneously the hydratation levels and urea localization into superficial cell layers. Urea crystallization after evaporation of emulsions and aqueous solutions is described. Results show that urea does not hydrate nor penetrate when applied to the skin through an aqueous gel. In a W/O emulsion, sodium chloride increases the ability of urea to moisturize without improving penetration. In vitro urea crystallization is disturbed by sodium chloride or magnesium sulphate for solutions and emulsions. This stabilization by ions is correlated with good moisturization values. The stabilization of urea in the solute state provided by ions increases its water epidermal binding capacity without enhancing penetration.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.