QuEChERS结合高效液相色谱法快速检测鸡肉中氟喹诺酮类药物残留

建立了QuEChERS-高效液相色谱法测定鸡肉中3种氟喹诺酮类药物残留的检测方法。鸡肉样品经酸化乙腈提取后,用无水Mg SO4、Na Cl干燥,用PSA与C18净化,将处理液用氮吹仪吹干,用初始流动相比例的溶剂复溶,用高效液相色谱进行检测。试验结果表明,依诺沙星、诺氟沙星、环丙沙星在1.0μg/kg～100μg/kg浓度范围内线性关系良好,相关系数R20.99,平均回收率在83.4%～112.0%之间,相对标准偏差(RSD)为3.2%～6.7%。     

HPLC法测定鳗鱼中三种喹诺酮药物残留

目的建立一种高效液相色谱方法测定鳗鱼中环丙沙星、恩诺沙星和恶喹酸3种喹诺酮类药物残留量,方法试样用含1％乙酸的乙腈提取,用正己烷脱脂、浓缩,缓冲盐＋乙腈（80＋20,体积分数）溶解,超高速离心净化,用荧光检测器测定,外标法峰面积定量。结果试样在10、0～60．0μg／kg范围内校正曲线呈良好的线性关系,3种物质的相关系数都在0．999以上。加标回收率：恶喹酸为87．4％～105．1％,环丙沙星为70．0％～85．7％,恩诺沙星为76.0％～92．8％,相对标准偏差均小于10％;检出限：恶喹酸为1.4μg／kg,环丙沙星为2．7μg／kg,恩诺沙星为1．5μg／kg。结论该方法操作简单、快捷．结果准确、可靠。     

鸡蛋中7种磺胺药物的多残留检测方法研究

本试验研究建立了高效液相色谱法测定鸡蛋中7种磺胺药物（磺胺嘧啶、磺胺二甲基嘧啶、磺胺甲氧哒嗪、磺胺间甲氧嘧啶、磺胺甲恶唑、磺胺间二甲氧嘧啶和磺胺喹恶啉）残留的提取、净化和高效液相色谱分析条件，鸡蛋经二氯甲烷提取、固相萃取、净化处理后上机检测，7种磺胺药物标准曲线的相关系数（R^2）为0．9995～0．9999，在0．05～0．2mg／kg浓度范围内，回收率为73．2％-102．6％，变异系数为1．8％～8．7％。检测限为0．01～0．02mg／kg，定量限低于0．05mg／kg。     

鸡肉中8种喹诺酮药物残留的高效液相色谱分析研究

建立了氧氟沙星(OF)、诺氟沙星(NF)、环丙沙星(HB)、达氟沙星(DF)、恩诺沙星(EN),二氟沙星(2F)、沙拉沙星(SA)、噁喹酸(OXL)8种喹诺酮类药物在鸡肉中残留的HPLC检测方法。流动相为0.1%三氟乙酸/三乙胺(pH3.0):甲醇:乙腈=82:12:6,勿需梯度洗脱,流速为1.0 mL/min使用双通道荧光检测器,检测波长为:A通道λex=280 nm,λem=480 nm,B通道λex=320 nm,λem=370 nm。方法的检出限氧氟沙星为0.0061 mg/kg、诺氟沙星为0.0036 mg/kg、环丙沙星为0.0046 mg/kg、达氟沙星为0.0012 mg/kg、恩诺沙星为0.0027 mg/kg、二氟沙星为0.0060 mg/kg、沙拉沙星为0.010 mg/kg、噁喹酸为0.012 mg/kg,各组分回收率在69.5%～110.5%,相对标准偏差为1.50%～6.73%。该方法简便、灵敏,可满足鸡肉中多种喹诺酮残留量的检测。     

QuEChERS -超高效液相色谱串联质谱法快速测定禽蛋中7种喹诺酮类兽药残留

建立一种超高效液相色谱串联质谱(ultra performance liquid chromatography-tandem mass spectrometry, UPLC-MS/MS)快速测定禽蛋中恩诺沙星、环丙沙星、氧氟沙星、培氟沙星、诺氟沙星、洛美沙星和沙拉沙星共7种喹诺酮类兽药残留的分析方法。禽蛋样品经体积分数为5%的甲酸-乙腈提取喹诺酮类兽药残留,QuEChERS净化后通过快速溶剂蒸发系统浓缩,采用C_(18)色谱柱分离,以体积分数为0.1%的甲酸和乙腈为流动相进行梯度洗脱,电喷雾离子源电离,多反应监测模式采集信号,基质外标法定量。结果表明,7种喹诺酮类兽药在2.0～100.0 ng/mL线性关系良好(R~2>0.995),方法的检出限和定量限分别为0.3和1.0μg/kg;添加2、5、10μg/kg三个浓度水平,平均回收率为77.20%～98.47%,相对标准偏差为1.5%～6.2%(n=6)。该方法简单快捷、准确度好、灵敏度高,适用于禽蛋中喹诺酮类兽药残留的快速确证。     

超临界流体萃取和高效液相色谱同时测定鸡肉中4种氟喹诺酮类药物残留

建立了一种超临界流体萃取(SFE)-高效液相色谱(HPLC)同时检测鸡肉中4种氟喹诺酮类药物(FQs)的方法。SFE萃取的适宜条件是温度80℃,系统压力为300kg/cm2,总流速为3mL/min,萃取时间为30min,夹带剂甲醇的比率为30%。萃取样品用高效液相色谱荧光检测器(激发光波长290nm,发色光波长455nm)外标法定量。氧氟沙星、诺氟沙星、环丙沙星和恩诺沙星在2.5～50μg/L浓度范围内线性良好,相关系数为0.9876～0.9996,其最低检出限为10～25μg/kg。在25～250μg/kg浓度范围内,平均加标回收率为56.6%～94.2%,相对标准偏差在1.4%～14.1%范围。     

QuEChERS-超高效液相色谱-串联质谱法同时测定畜禽肉中11 种喹诺酮类兽药残留

建立一种超高效液相色谱-串联质谱法测定畜禽肉中恩诺沙星、环丙沙星、氧氟沙星、培氟沙星、诺氟沙星、洛美沙星、沙拉沙星、双氟沙星、司帕沙星、氟罗沙星和达氟沙星共11 种喹诺酮类兽药残留的检测方法。畜禽肉样品经2%甲酸-乙腈均质提取,离心沉淀后上清液经QuEChERS净化剂净化后,经快速溶剂蒸发系统浓缩,采用Waters BEH C18色谱柱（2.1 mm×50 mm,1.7 μm）分离,以0.1%甲酸-水和0.1%甲酸-乙腈为流动相进行梯度洗脱,电喷雾离子源电离,多反应监测模式采集信号,内标法定量。结果表明：11 种喹诺酮类兽药在2～80 ng/mL质量浓度范围内线性关系良好（R2＞0.99）,方法的检出限和定量限分别为0.5～2.0 μg/kg和1.5～6.0 μg/kg;空白样品加标量为10、25、50 μg/kg 3 个水平时,11 种喹诺酮类兽药的平均加标回收率为74.52%～106.83%,相对标准偏差为1.8%～8.7%（n=6）。该方法检测过程简单快捷、准确度好、灵敏度高,适用于畜禽肉中喹诺酮类兽药残留的检测。     

高效液相色谱法同时测定水产品中6 种喹诺酮药物的残留

建立用固相萃取- 反相高效液相色谱法同时检测水产品中6 种喹诺酮药物残留量的方法。通过对提取方法和C18 固相萃取柱净化条件、色谱条件选择与优化、洗脱液浓度和用量的选择方面的研究,确定采用高效液相色谱分离、荧光检测器检测、外标法定量的分析方法。本方法对环丙沙星、恩诺沙星、氧氟沙星、诺氟沙星、噁喹酸、氟甲喹标准曲线的线性回归系数均在0.99 以上,线性范围为0.02～2.0μg/mL。以3 倍信噪比RSN 计算,环丙沙星、恩诺沙星、诺氟沙星、氧氟沙星检出限为2μg/kg,噁喹酸、氟甲喹检出限为5μg/kg;以10 倍信噪比RSN 计算,环丙沙星、恩诺沙星、氧氟沙星、诺氟沙星的定量下限为5μg/kg;噁喹酸、氟甲喹的定量下限为10μg/kg。在南美白对虾、罗非鱼、鳗鱼、斑点叉尾鮰中进行这6 种喹诺酮类药物加标回收率的验证实验,实验结果满意,回收率在78.8%～92.9% 之间;相对标准偏差为2.97%～7.10%。说明本方法简单、灵敏,结果可靠,可用于水产品中环丙沙星、恩诺沙星、氧氟沙星、诺氟沙星、噁喹酸、氟甲喹的同时检测。     

水兼容性分子烙印固相萃取-高效液相色谱法测定鸡肉中氟喹诺酮类药物残留

目的：建立分子烙印固相萃取-高效液相色谱测定鸡肉中氟喹诺酮类药物残留的新方法。方法：以甲基丙烯酸为功能单体,恩诺沙星为模板分子,在强极性溶剂甲醇-水体系中制备分子烙印聚合物,考察和评价分子烙印聚合物的特性。鸡肉样品经乙腈提取浓缩后过分子烙印固相萃取柱,乙腈-三氟乙酸(99:1,V/V)洗脱液由高效液相色谱分离和荧光法检测。结果：高亲合力的结合位点的解离常数为Kd1=7.19×10-5 mol/L,最大表观结合位点数Qmax,1=110.19μmol/g;低亲和力结合位点的解离常数为Kd2=2.44×10-3mol/L,最大表观结合位点数Qmax,2 = 965.51μmol/g。氧氟沙星、诺氟沙星、环丙沙星和恩诺沙星等氟喹诺酮类药物的校准曲线在1.0～500 μg/kg范围内呈良好的线性关系(r≥0.9991),检出限(S/N=3)为0.06～0.09μg/kg,平均回收率为75.4%～86.4%(n=3),相对标准偏差小于6%。结论：以水兼容性分子烙印固相萃取-高效液相色谱法可实现氟喹诺酮药物的有效分离和灵敏测定。     

基于QuEChERS方法的鸭蛋兽药残留快速检测方法的构建

试验建立了基于QuEChERS法测定鸭蛋中4种大环内酯类(红霉素、替米考星、吉他霉素和泰乐霉素)和4种喹诺酮类(诺氟沙星、环丙沙星、洛美沙星和恩诺沙星)抗生素的方法,用于高效快速检测鸭蛋中兽药残留情况。样品经前处理后,以0.2%甲酸-水溶液和0.2%甲酸-乙腈溶液作为流动相,采用梯度洗脱方式进行UPLC-ESIMS/MS检测。结果表明, 4种大环内酯类和4种喹诺酮类化合物在1～100μg/kg浓度范围内线性关系良好,相关系数(R~2)均大于0.99,检出限为0.010～0.174μg/kg,定量限为0.034～0.576μg/kg。采用5, 50和100μg/kg的标准液添加浓度得到的回收率均在70%以上,相对标准偏差(RSD)小于10%(个别除外)。该方法灵敏度高,重复性好,操作简便,效率极高,各项技术指标均满足国内外相关法规要求,可用于鸭蛋样品中兽药残留的分析检测。     

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.