胶体金免疫层析法快速检测动物源性食品中土霉素残留

为建立用于快速检测食品中土霉素残留的胶体金免疫层析试纸条。本试验用柠檬酸三钠还原法制备胶体金,胶体金粒径选用20 nm,经鉴定将制备成功的胶体金溶液与土霉素多克隆抗体结合得到金标抗体。优化金标抗体的制备条件,经鉴定金标抗体制备成功。将检测抗原（1.0 mg/mL）和羊抗鼠二抗（0.75 mg/mL）分别作为检测线和质控线包被在硝酸纤维素膜（NC膜）上,金标抗体按一定浓度包被在玻璃纤维垫上,对样品垫和吸收垫进行裁剪处理,通过上述预处理将每部分依次叠加粘贴至底板,制成胶体金试纸条。结果表明,土霉素胶体金试纸条的检出限为25 μg/L;土霉素胶体金免疫层析试纸条与其他常见兽药（非本族兽药）无交叉反应。该试纸条具有较强特异性、检测时间短、操作方便等优点,可作为土霉素残留现场检查的有效手段。     

胶体金免疫层析捕获法检测人血清中肺炎支原体IgM抗体

采用胶体金标记鼠抗人IgMμ链抗体,肺炎支原体P1抗原作包被蛋白,检测肺炎支原体特异性抗体IgM.经对免疫金制备条件进行优化,制备了胶体金免疫层析检测试纸条.将该试纸条与市售试剂盒作对比检测,总符合率为99.17%,表明本方法灵敏度较高、特异性较强,价格低,操作简便快捷,更适合MP感染患者早期临床筛查.     

呋喃它酮代谢物5-甲基吗啉-3-氨基-2-恶唑烷酮单克隆抗体的制备、鉴定与胶体金免疫层析试纸条的研制

目的:制备5-甲基吗啉-3-氨基-2-恶唑烷酮(AMOZ)单克隆抗体,并建立AMOZ胶体金试纸条检测方法.方法:AMOZ与对醛基苯甲酸反应生成半抗原CP-AMOZ,将CP-AMOZ与BSA、OVA偶联制备完全抗原.免疫小鼠后制备腹水型抗体,ELISA检测抗体效价与其对CP-AMOZ半抑制浓度(IC50)和最低检测限(LOD),并检测抗体的特异性.胶体金与单抗偶联,同时在NC膜上包被完全抗原、兔抗鼠多抗分别作为检测线和质控线,制备免疫层析试纸条,测定试纸条的灵敏度与特异性.结果:成功制备CP-AMOZ-BSA、CP-AMOZ-OVA完全抗原及抗CP-AMOZ的单抗,抗体效价为1∶1.6×105,对CP-AMOZ IC50为0.86μg/L,LOD 0.07 μg/L,与其他硝基呋喃类药物代谢物及其衍生物均无交叉反应.制备的胶体金试纸条灵敏度5 μg/L.结论:成功合成了CP-AMOZ的完全抗原,免疫小鼠后制备了特异性强的单抗,并以此为基础研制出敏感、特异的胶体金快速检测试纸条.     

基于单克隆抗体的胶体金免疫层析法快速检测丁香酚

目的 采用免疫层析技术对丁香酚残留的胶体金免疫层析快速检测试纸条的制备开展研究。方法 用柠檬酸三钠还原法制备胶体金纳米颗粒, 标记丁香酚单克隆抗体得到胶体金-丁香酚单克隆抗体复合物。以硝化纤维素膜为固相载体, 包被丁香酚-BSA偶联物为检测带(T带), 羊抗鼠IgG为质控带(C带), 建立了丁香酚的胶体金免疫层析快速检测试纸条。结果 胶体金免疫层析试纸条具有较高的灵敏度和特异性, 检出限为2.0 mg/L。结论 本研究所开发的胶体金免疫层析试纸条可作为快速测定丁香酚的可靠、低成本的方法。     

单增李斯特菌胶体金免疫层析试纸条的研制

以单增李斯特菌(LM)内化素A蛋白(InlA)单克隆抗体为基础,研制其胶体金免疫层析检测试纸条。方法 采用DNAStar软件对LM inlA全长基因编码蛋白进行抗原表位分析,截取部分inlA基因片段构建原核表达质粒,诱导表达和纯化获得重组蛋白。以该蛋白免疫BALB/c小鼠,筛选高效分泌抗InlA单克隆抗体的杂交瘤细胞株,制备单克隆抗体;以双抗体夹心的原理研制胶体金免疫层析检测试纸条,并对其特异性、敏感性、稳定性进行评价。结果 筛选到2株高效分泌抗InlA单克隆抗体的杂交瘤细胞株,抗体属于IgG1亚类,小鼠腹水抗体效价为1∶64000;研制的试纸条可与LM发生阳性反应,而与非LM李斯特菌、链球菌、鼠伤寒沙门菌、大肠杆菌O157∶H7等食源性致病菌均不发生阳性反应;LM纯培养物敏感性为2.4×10^5cfu/ml,模拟猪肉样品敏感性为4.0×10⁶ cfu/ml;4℃保存期可达16周以上。结论 研制的胶体金免疫层析试纸条具有快速、特异、敏感等优点,可以用于样品中LM的快速检测。     

胶体金免疫层析法测定牛羊肉中掺杂鸡肉

目的建立胶体金免疫层析法快速检测牛羊肉中掺杂鸡肉的方法。方法采用柠檬酸三钠制备胶体金溶液,以真空干燥的方式制备有金标抗体的微孔试剂,将鸡IgY包被于硝酸纤维素膜(NC膜)的检测线(T线),兔抗羊抗体包被于硝酸纤维素膜(NC膜)的质控线(C线),向硝酸纤维素膜依次贴上吸水纸和样品垫,切条组装成试纸条。样品经磷酸盐处理,加入至金标抗体的微孔中,用试纸条检测,胶体金分析仪检测T/C线的颜色信号。结果该方法对牛羊肉中掺入鸡肉的检出限为3%,重复性和特异性较好,其他动物组织对其无干扰,检测时间仅需要15 min。结论该方法操作简便,具有较高的灵敏度和特异性,适用于牛羊肉中掺杂鸡肉的现场快速筛查和检测。     

胶体金免疫层析法快速检测动物组织中残留的喹乙醇

研制胶体金免疫层析法试纸条,用于动物源食品中喹乙醇药物残留的快速检测。将已制备纯化过的喹乙醇多克隆抗体与胶体金结合产生的金标抗体喷涂在玻璃纤维垫上,并将包被抗原OLA-OVA和羊抗鼠二抗分别结合在硝酸纤维素膜上,组装成免疫层析快速检测试纸条,并检测试纸条的灵敏度、特异性、准确性和稳定性。将制备的试纸条用于检测猪肉和猪肝样品,结果表明本研究制备的试纸条可以在10min内完成检测,肉眼观察的最低检测限为0.05μg/m L,与其结构类似物卡巴氧、乙酰甲喹、3-甲基-喹噁啉-2-羟酸的反应交叉性小,该试纸条假阳性率小于5%,假阴性率为0,在干燥常温条件下保存6个月仍然有效。本实验研究的检测方法可应用于动物组织中喹乙醇的快速检测和现场筛查。     

乳品中多种抗生素残留胶体金检测方法研究

研究用于牛奶和奶粉中多种抗生素残留同时检测的胶体金免疫层析试纸条。基于胶体金免疫层析技术,搭建抗原包被体系和胶体金标记抗体体系,优化检测方法,考察胶体金快速检测试纸条的检测灵敏度、特异性、准确度和实际样本适应性。试纸条可同时检测卡那霉素、红霉素、林可霉素3种药物在牛奶、奶粉中的残留,检测限分别为50.0,20.0和75.0μg/L,假阳性率和假阴性率均为0,样本无需前处理,检测操作简单,10 min内实现3种药物同时检测。采用胶体金试纸条和液相色谱串联质谱法对20份牛奶和奶粉盲样进行比对试验,阳性样品全部检出,2种方法测定结果一致。建立的胶体金免疫层析技术及试纸条检测准确可靠,适用于现场大批量样本的快速检测和筛选。     

胶体金免疫层析法检测食用肉中的氨基脲

制备特异性胶体金免疫层析试纸条,检测肉类食品中氨基脲的残留。用活性酯法将氨基脲(SEM)衍生物CPSEM交联到牛血清白蛋白(BSA)上制备完全抗原CPSEM-BSA,将硫酸铵沉淀法纯化的抗CPSEM单克隆抗体标记到柠檬酸三钠还原法制备的胶体金,通过优化C/T线及金标抗体工作浓度,制备检测氨基脲的胶体金免疫层析试纸条,并对试纸条的灵敏度、特异性、准确性和稳定性进行测定。制备的试纸条检测5min后即可用肉眼观察到结果;对SEM的最低检测限达0.72ng/ml;除与呋喃西林有弱交叉反应外,与其他同类物均无交叉反应;该试纸条对猪肉中添加的SEM检测结果与酶联免疫吸附测定法(ELISA)检测结果呈现了很好的相关性;试纸条在室温下保存7周后不会失效。通过制备针对SEM的试纸条所建立的胶体金免疫层析法(ICA),快速简便、灵敏度高、特异性强、准确性和稳定性好,基本能达到商用检测要求。     

胶体金免疫层析法快速检测氯霉素残留

为建立用于快速检测样品中氯霉素残留含量的胶体金免疫层析试纸条，采用免疫竞争法，将抗氯霉素单克隆抗体一胶体金复合物包被在胶体金结合垫上，并将人工合成的氯霉素抗原包被在硝酸纤维素薄膜表面作为检测线（T线），其与待测样品中氯霉素竞争结合胶体金标记的氯霉素单克隆抗体，并能以颜色直观显示检测的定性结果。检测虾肉等组织试样时，灵敏度最低值可达到1ng／ml，只需5—10min，与类似物无交叉反应。试纸条具有较高的灵敏度及特异性，操作便捷．稳定可靠，可作为氯霉素残留现场监控的有效筛检手段。     

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.     

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.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.     

低温带皮菜籽粕微粉的不同粒级部分的功能特性

为研究低温带皮菜籽粕微粉的不同粒级部分的功能特性,以经低温脱脂的带皮菜籽粕为原料,经微粉碎后筛分成212~425μm、150~212μm和106~150μm的3个不同粒级的微粉样品,检测这些样品的吸水性、吸油性、乳化性和乳化稳定性、蛋白质体外消化率。结果表明:1 3个不同粒级的微粉样品之间的粗纤维含量存在显著差异,表明三者的结构组成成分有一定差异。23个微粉样品的乳化活性和乳化稳定性随粒度级别的减小而显著增加(P0.01)。33个微粉样品的蛋白质体外消化率随粒度级别的减小而显著增加(P0.01)。4不同粒级带皮菜籽粕微粉样品的吸水性与吸油性受其结构组成物质不同和粒度的双重影响,与粒度的相关性不明显。     

Microbiology of food taints

Fresh and processed foods are often spoilt by the presence of undesirable flavours and odours caused by microbial action. The aim of this paper is to review the current knowledge of microbiologically induced taints that occur in a wide range of foodstuffs, including meats, poultry, fish, crustaceans, milk, dairy products, fruits, vegetables, cereals and cereal products. Examples have been chosen where the compounds responsible for the taint have been identified and sufficient data obtained to demonstrate the involvement of microorganisms. However, in some cases the full identity of the causative organism may not have been elucidated. The types of microorganisms covered by this review include bacteria, fungi, yeasts, actinomycetes and cyanobacteria. Although cyanobacteria do not in general infect foods, their presence in aqueous systems and water supplies can lead to off-flavours in aquatic organisms and processed foodstuffs. Several examples of each of these processes are discussed. Wherever possible, the likely biosynthetic pathway used by the microorganism to produce the offending compound in a foodstuff is indicated.     

Analysis for organic residues from aids to polymerization used to make plastics intended for food contact

Polymers intended for food contact use have been analysed for organic residues which could be attributed to a range of substances employed as polymerization aids (e.g. initiators and catalysts). A wide range of polymers was extracted with solvents and the extracts analysed by gas chromatography-mass spectrometry (GC-MS). The overwhelming majority of substances identified were not derived from aids to polymerization but were oligomers, additives and adventitious contaminants. However, a small number of substances were identified as initiator residues. These included tetramethylsuccinonitrile (TMSN) which was observed in two polymers and it derived from recombination of two azobisisobutyronitrile (AIBN) initiator radicals. Methyl benzoate, benzoic acid, biphenyl and phenyl benzoate were detected in one poly(methyl methacrylate) sample and in two polyvinylchlorides and they are thought to be derived from benzoyl peroxide initiator. TMSN was subsequently targeted for analysis of poly-(methyl methacrylate) plastics using proton nuclear magnetic resonance spectrometry (¹     

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

Experiments were performed to characterize the kinetics of the permeation of different medium molecular weight model permeants: bisphenol A, warfarin and anthracene, from liquid paraffin, through a surrogate potential functional barrier (25 microns-thick orientated polypropylene--OPP) into the food simulants olive oil and 3% (w/v) acetic acid. The characterization of permeation kinetics generally observed the permeation models previously reported to explain the experimental permeation results obtained for a low molecular weight group of model permeants. In general, the model permeants exhibited behaviour consistent with their relative molecular weights with respect to (a) the time taken to attain steady-state permeation into the food simulant in which they were more soluble, (b) their subsequent steady-state permeation rates, and (c) their partition between liquid paraffin and the OPP membrane.     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. I: Interlaboratory studies of methods of analysis

This paper describes the first part of a project undertaken to develop mussel reference materials for Paralytic Shellfish Poisoning (PSP) toxins. Two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin (STX) and decarbamoyl-saxitoxin (dc-STX) in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the second part of the project: the certification exercise. In the first study, 18 laboratories were asked to measure STX and dc-STX in rehydrated lyophilized mussel material and to identify as many other PSP toxins as possible with a method of their choice. In the second interlaboratory study, 15 laboratories were additionally asked to determine quantitatively STX and dc-STX in rehydrated lyophilized mussel and in a saxitoxin-enriched mussel material. The first study revealed that three out of four postcolumn derivatization methods and one pre-column derivatization method sufficed in principle to determine STX and dc-STX. Most participants (13 of 18) obtained acceptable calibration curves and recoveries. Saxitoxin was hardly detected in the rehydrated lyophilized mussels and results obtained for dc-STX yielded a CV of 58% at a mass fraction of 1.86 mg/kg. Most participants (14 out of 18) identified gonyautoxin-5 (GTX-5) in a hydrolysed extract provided. The first study led to provisional criteria for linearity, recovery and separation. The second study revealed that 6 out of 15 laboratories were able to meet these criteria. Results obtained for dc-STX yielded a CV of 19% at a mass fraction of 3.49mg/kg. Results obtained for STX in the saxitoxin-enriched material yielded a CV of 19% at a mass fraction of 0.34mg/kg. Saxitoxin could not be detected in the PSP-positive material. Hydrolysis was useful to confirm the identity of GTX5 and provided indicative information about C1 and C2 toxins in the PSP-positive material. The methods used in the second interlaboratory study showed sufficiently consistent analysis results to undertake a certification exercise to assign certified values for STX and dc-STX in lyophilized mussel.     

The Ministry of Environmental Protection Issued "Feasible Technology Guidelines for Pollution Prevention and Control in Wood Pulping Process of the Paper Industry (Trial)" and Two Other Guiding Technical Documents

On December 27t＂, 2013, the Ministry of Environmenta Protection announced that, in order to implement ＂The Environmental Protection Law of the People＇ s Republic of China＂, improve the working system in environmenta protection technologies, and promote technologica advancement in pollution prevention, the Ministry of Environmental Protection sponsored the formulation of three guiding technical documents including ＂Feasible Technology Guidelines for Pollution Prevention and Contro n Wood Pulping Process of the Paper Industry （Trial）＂     

1~(st) Intelli-Tissue~ EcoEc Tissue Machine Supplied by PMP Group Successfully Put into Operation in China

正On April 29th,2014,Intelli-Tissue EcoEc tissue machine supplied by PMP Group successfully put into operation at Hebei Xuesong Paper Co.,Ltd.,this is the first such kind of paper machine of PMP Group in China.