超高效液相色谱-串联质谱法检测鱼中孔雀石绿、结晶紫及其代谢物

采用超高效液相色谱-串联质谱法同时测定鱼中孔雀石绿（malachite green,MG）、隐性孔雀石绿（leuco malachite green,LMG）、结晶紫（crystal violet,CV）、隐性结晶紫（leuco crystal violet,LCV）4 种物质残留。样品加入内标物D5-MG、D6-LMG、D5-CV、D6-LCV,经乙腈提取、离心、过中性氧化铝柱,氮气吹至近干,50%乙腈溶液定容,上机测定。MG和LMG线性范围为1～50 ng/mL,CV和LCV线性范围为1～100 ng/mL。4 种物质的检出限均为0.05 μg/kg,定量限均为0.15 μg/kg。在50、100、200 ng/mL 3 个添加水平下,回收率在87.80%～110.82%之间,相对标准偏差均小于等于4.32%（n=6）。该方法灵敏、准确、可靠,可以同时测定鱼中MG、LMG、CV、LCV残留。     

高效液相色谱串联质谱法测定水产品中的孔雀石绿和结晶紫

目的建立高效液相色谱串联质谱法检测水产品中孔雀石绿、隐色孔雀石绿、结晶紫、隐色结晶紫残留量的方法。方法待检水产品经乙腈提取,中性氧化铝固相萃取柱净化, 0.22μm微孔滤膜过滤后用高效液相色谱串联质谱进行检测。结果 4种化合物在0～100.0ng/mL浓度范围内线性关系良好,相关系数大于0.999,检出限均可达到0.25μg/kg,回收率为85%～110%,相对标准偏差均小于10%。结论本方法使用试剂少、步骤简单,适用于大批量水产品中孔雀石绿和结晶紫残留量的检测。     

养殖水产品中孔雀石绿、结晶紫及其代谢产物的前处理方法研究

根据SN/T 1768-2006、GB/T 19857-2005、GB/T 20361-2006标准,比较适合以上标准的3种水产品前处理方法,即:固相萃取法、旋转蒸发法、氮气吹干法.采用液相色谱串联质谱(LC-MS)检测水产品中孔雀石绿(MG)、结晶紫(CV)含量.以3种前处理方法所得回收率为指标,确定固相萃取法为适合的方法.换用不同的固相萃取小柱,对固相萃取法进行优化,以获得最大回收率.结果表明固相萃取小柱LH的最佳回收率超过88％,该固相小柱的重复使用回收率损失仅3％.该方法简便、快速、灵敏,适于水产品中孔雀石绿及其代谢物隐色孔雀石绿,结晶紫及其代谢物隐色结晶紫残留量的检测.     

养殖水中孔雀石绿、隐色孔雀石绿、结晶紫、 隐色结晶紫、亚甲基蓝残留量的测定

目的建立一种高效液相色谱-串联质谱同时测定养殖水体中孔雀石绿、结晶紫及其代谢物和亚甲基蓝残留量的方法。方法将水样用盐酸羟胺-对甲苯磺酸溶液和乙腈提取,二氯甲烷萃取2次后浓缩,用1 mL乙腈-5 mmol/L乙酸铵(1:1,V:V)定容。以乙腈-5 mmol/L乙酸铵(85:15,V:V)混合溶液为流动相进行色谱分离,然后进入串联质谱仪,选用电喷雾离子源,在正离子、多反应监测扫描模式下进行定性,孔雀石绿和结晶紫通过内标法定量,亚甲基蓝通过外标法定量。结果在优化条件下,孔雀石绿、隐色孔雀石绿、结晶紫、隐色结晶紫在0.025~0.600 ng/mL浓度范围内,亚甲基蓝在0.05~1 ng/mL浓度范围内均满足线性关系,相关系数r0.99,方法检出限为0.2 ng/mL。加标浓度在0.2~2.0 ng/mL时,孔雀石绿、隐色孔雀石绿、结晶紫、隐色结晶紫和亚甲基蓝的平均回收率均在70%~110%之间,相对标准偏差均在10%以内。结论该方法简单快速、灵敏度高、前处理成本低、重现性好、回收率高,适用于同时检测养殖水体中孔雀石绿、隐色孔雀石绿、结晶紫、隐色结晶紫、亚甲基蓝残留量。     

一种高效检测水产品中孔雀石绿和结晶紫残留量的方法

提供了一种高效检测水产品中孔雀石绿和结晶紫残留量的方法。待检水产品以目标化合物相应的同位素为内标,经乙腈提取,中性氧化铝柱净化,孔径0.22μm微孔滤膜过滤后用高效液相色谱质谱联用仪检测。结果表明,对不同水产品进行结果验证,4种待测物(孔雀石绿、隐色孔雀石绿、结晶紫、隐色结晶紫)的回收率为85%~120%,检出限均可达到0.5μg/kg,标准曲线相关系数0.999以上。与现有检测方法相比,该方法使用试剂少、步骤简单,适用于水产品中孔雀石绿和结晶紫的大批量检测。     

用LC/MS/MS快速检测食品中的孔雀石绿、结晶紫、隐性孔雀石绿、隐性结晶紫

孔雀石绿（MG）和结晶紫（CV）为三苯甲烷类染料,因价格低廉、使用方便,常用于鱼类水霉病等寄生虫病的防治或作为消毒剂用于鲜活鱼类运输过程中,以延长鱼类的存活时间。实验研究表明,孔雀石绿或结晶紫进入人或动物机体后,可以通过生物转化,还原代谢成脂溶性的无色孔雀石绿（LMG,也叫隐性孔雀石绿）或无色结晶紫（LCV,也叫隐性结晶紫）。LMG、LCV具有高毒性．高残留和致癌、致突变等副作用,严重威胁着消费者的身体健康。     

HPLC-MS/MS同位素内标法测定水体中孔雀石绿、结晶紫及其代谢物

建立用氘代同位素测定水中孔雀石绿、结晶紫及其代谢物隐性孔雀石绿、隐色结晶紫的高效液相色谱-串联质谱法。水样中加入内标,经二氯甲烷提取后,MRM定量。孔雀石绿和结晶紫检出限均为为0.50ng/L,定量限均为2.00ng/L;隐色孔雀石绿和隐色结晶紫检出限均为0.25ng/L,定量限分别为1.50、1.20 ng/L。在1.0、2.5、10.0ng/L三个浓度水平加标回收率范围在85.0%~105.5%之间,RSD在1.6%~6.7%内。该方法处理经济高效、响应灵敏,准确度、精密度好,满足水样中三苯甲烷类化合物及其代谢物的准确定性、定量要求。     

介质阻挡放电电离质谱法快速筛查水产品中孔雀石绿及其代谢物

建立了采用介质阻挡放电电离质谱（DBDI-MS/MS）技术对水产品中孔雀石绿（MG）及其代谢物隐色孔雀石绿（LMG）进行快速筛查的方法。样品经提取净化后,在氦气流量为3 L/min、离子源温度为230℃的DBDI离子源条件下,正离子模式下采用多反应监测（MRM）进行质谱检测。在此条件下,MG和LMG在1~20 μg/L范围内,相关系数r值分别为0.9951、0.9939,线性关系良好,MG和LMG的检出限均为1 μg/kg,样品加标回收率为61.8%~78.4%。该方法样品前处理简便,无需液相色谱分离,耗时短,适用大批量水产品中孔雀石绿非法添加的快速筛查。     

水中孔雀石绿、结晶紫残留量的同时测定

建立固相萃取-高效液相色谱法测定水中孔雀石绿、结晶紫的残留量。以硼氢化钾溶液将孔雀石绿、结晶紫还原为隐色孔雀石绿、隐色结晶紫,乙腈/二氯甲烷提取残留物,提取液依次通过酸性氧化铝柱/PRS柱净化、洗脱。结果表明:该方法能很好的除去水中的干扰物,方法回收率在84%～93%,隐色孔雀石绿的最低检出限为0.96μg/L,隐色结晶紫的最低检出限为1.02μg/L,适合于水中孔雀石绿、结晶紫的分析测定,具有良好的实验室应用前景。     

水产品中孔雀石绿检测方法的研究进展

孔雀石绿(malachite green, MG)由于其对水产品疾病防治的高效性和低廉的成本而被广泛用作水产养殖业的杀菌剂和杀寄生虫剂, 因此常见于水产品和环境用水中。但是, MG及其主要代谢产物隐性孔雀石绿(leuco-malachite green, LMG)也是有毒的有机污染物, 对人体和其他生物的健康有害。近年来, 已经提出了用于检测MG和LMG的多种方法。用于测定各种基质中MG和LMG的分析方法包括高效液相色谱法(与紫外-可见、荧光、质谱等检测器联用)、光谱法(紫外-可见分光光度法、荧光法、表面增强拉曼光谱法等)、电化学方法、免疫学测定法(酶联免疫法、化学发光免疫法、免疫层析法等)。本文对近10年来孔雀石绿和隐性孔雀石绿的检测方法进行综述, 并讨论了孔雀石绿和隐性孔雀石绿的未来检测发展趋势和所面临的挑战, 为水产中孔雀石绿的检测方法提供一定参考。     

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.     

Focus on China's Paper Industry

In the English section of this issue, 〈China Paper Newsletters〉 will introduce ＂National Development and Reform Commission Issued Announcement for Selection of Major Preliminary Research Projects for the ＇13th Five-Year Plan＇＂, ＂2013 Annual Report of China＇s Paper Industry＂, and news of projects and other policies.     

Listen to downstream & search for innovation

正Nowadays,textile enterprises are all taking efforts in transformation and upgrading,like improving producing capacity and optimizing production structure to face market downturn.It claimed a higher request to the standard of textile equipments.In the upcoming of ITMA ASIA+CITME 2014exhibition,this magazine have interviewed several branch associations and a series of relative enterprises,to summarize industrial developing status