UPLC-MS/MS法测定牛奶和豆乳中百草枯和敌草快的残留量

建立超高效液相色谱-串联质谱法（UPLC-MS/MS）测定牛奶和豆乳两种基质中百草枯和敌草快残留量的检测方法。5 g样品经甲酸酸化超声20 min,涡旋振荡5 min辅助提取,加入10 m L甲醇,涡旋振荡5 min,15 000 r/min离心10 min。上清液经正己烷脱脂,在电喷雾离子源正离子条件下检测,同时考察了牛奶和豆乳样品的基质效应。结果表明,牛奶和豆乳基质中百草枯和敌草快检出限均为0.001 5 mg/kg,定量限均为0.002 5 mg/kg。百草枯和敌草快在两种基质中的基质效应较强,需要以基质内标标准曲线进行定量校正。在百草枯和敌草快标准品添加范围为0.0025～0.025 mg/kg时,回收率在74.8%～115.6%之间,精密度试验结果相对标准偏差（RSD）为2.8%～7.7%。方法操作简单快速,适用于牛奶和豆乳样品中百草枯和敌草快的检测。     

高效液相色谱-串联质谱法快速测定食物中毒样品中的百草枯和敌草快

目的建立高效液相色谱-串联质谱法快速检测食物中毒事件中常见样品(如食品、血液及尿液等)中百草枯和敌草快的分析方法。方法分别以乙酸乙酯为溶剂提取食品和尿液样品、以乙腈为溶剂提取血液样品中的百草枯和敌草快,提取液氮吹浓缩至近干,加入流动相复溶,再经0.22μm滤膜过滤。采用WATERS ACQUITY UPLC BEH Amide色谱柱分离,以乙腈(A)-100 mmol/L甲酸铵溶液(含0.05%甲酸)(B)(60:40,V:V)为流动相等度洗脱,多反应模式监测,外标法定量。结果百草枯和敌草快在2.0~100μg/L质量浓度范围内线性关系良好,相关系数为0.9971~0.9999。百草枯和敌草快的检出限(S/N=3)分别为1.0μg/L和0.3μg/L,定量限(S/N=10)分别为3.0μg/L和1.0μg/L。加标水平为2.0、10.0、80.0μg/L时,百草枯和敌草快回收率分别为82.4%~98.4%和90.1%~103.5%,相对标准偏差分别为0.8%~5.1%和1.0%~4.2%。结论本方法建立的分析过程样品前处理简单、快速、准确,适用于食品、血液和尿液中的百草枯和敌草快的同时测定。     

GC-MS/MS法测定水果、蔬菜中敌草快的残留量

建立水果、蔬菜中敌草快残留量的气相色谱-串联质谱(GC-MS/MS)检测方法,比较硼氢化钠、硼氢化钾2种衍生化试剂用于敌草快衍生化反应的差异。果蔬样品经纯净水超声提取,中性氧化铝净化,硼氢化钠或硼氢化钾衍生,采用GC-MS/MS多反应监测模式分析,外标法定量。结果表明,采用优化后条件,敌草快在0.01～1.00 mg/kg定量范围内,线性关系良好,相关系数均在0.99以上。选取10种不同基质的果蔬样品,在空白样品中添加浓度为0.02, 0.05和0.10 mg/kg不同水平的敌草快标准溶液,敌草快的平均回收率为71.3%～95.3%,相对标准偏差小于6.4%。敌草快经2种衍生化试剂衍生后响应接近,采用硼氢化钠或硼氢化钾均可用于敌草快的衍生化反应。敌草快的检出限(S/N=3)和定量限(S/N=10)分别为2.1μg/kg和6.4μg/kg。方法操作简便、灵敏、准确、分析速度快、抗干扰能力强,适用于果蔬中敌草快残留量的定性、定量分析。     

气相色谱-正化学源-串联三重四极杆质谱法测定面包中氨基甲酸乙酯

建立了以气相色谱-正化学源-串联三重四极杆质谱(gas chromatography-positive chemical ionization-tandem triple quadruple mass spectrometry, GC-PCI-MS/MS)测定面包中氨基甲酸乙酯含量的方法。面包样品添加氨基甲酸乙酯同位素内标后,经10 g/100 mL(质量浓度)乙酸铅水溶液提取及沉淀蛋白,Cleanert EC碱性硅藻土固相萃取柱净化后,利用气相色谱-正化学源-串联质谱法检测提取溶液,利用多反应监测模式(multiple reaction monitoring,MRM)分析,内标法定量。结果表明,氨基甲酸乙酯在0.5～50.0μg/L范围内,线性良好,相关系数为0.999 5,检出限(limit of detection, LOD)为0.12μg/kg,定量限(limit of quantification,LOQ)为0.40μg/kg。在阴性样品添加的质量浓度分别为2.0、10.0、50.0μg/kg三个加标水平试验中,回收率为89.3%～95.6%,日内精密度为1.3%～4.6%,日间精密度为4.5%～9.9%。该方法高效、准确、选择性强,灵敏度和精密度均满足面包中氨基甲酸乙酯痕量检测要求。     

固相萃取-同位素稀释-UPLC-MS/MS法检测茶叶中百草枯和敌草快残留量

文章建立了茶叶中百草枯和敌草快的同位素稀释-UPLC-MS/MS检测方法。茶叶样品经提取、离心,使用PCX强阳离子交换小柱固相萃取净化,采用资生堂,Capcell PAK,ST,5μm,150 mm×2.0 mm色谱柱分离后UPLC-MS/MS检测,内标法定量。该方法对百草枯和敌草快的检测限为0.004 mg/kg和0.001 mg/kg;百草枯回收率在94.6%～103.4%之间,精密度RSD在0.7%～8.0%之间(n=6);敌草快回收率在99.5%～107.9%之间,精密度RSD在0.5%～5.7%之间(n=6);百草枯和敌草快在5～250 ng/mL浓度范围内均呈良好的线性关系,线性回归系数R20.999。该方法定性、定量准确,灵敏度高,能很好地应用于茶叶中百草枯和敌草快的检测。     

液相色谱-串联质谱法快速测定鸡蛋中金刚烷胺、氟苯尼考和氟苯尼考胺残留量

目的建立同时测定鸡蛋中金刚烷胺、氟苯尼考及氟苯尼考代谢物氟苯尼考胺残留的液相色谱-串联质谱(liquid chromatography-tandem mass spectrometry, LC-MS/MS)快速分析方法。方法鸡蛋样品用1.0%乙酸乙腈提取,提取后用PSA和C_(18)净化,氮吹后用流动相复溶,复溶液过滤膜后进行液相色谱-串联质谱测定。分析采用XBridge C_(18)色谱柱,以0.02%甲酸溶液和甲醇乙腈混合溶剂为流动相进行梯度洗脱,正负离子切换监测模式下进行监测,同位素内标法定量。结果3种化合物在一定浓度(氟苯尼考为0.10～20μg/L,金刚烷胺和氟苯尼考胺为0.5～100μg/L)范围内具有较好的线性关系,金刚烷胺、氟苯尼考和氟苯尼考胺的检出限(limit of detection, LOD)分别为0.3、0.06、0.3μg/kg,定量限(limit of quantitation, LOQ)分别为1.0、0.20、1.0μg/kg。当3种化合物在鸡蛋中的加标水平为LOQ、5LOQ和10LOQ时,平均回收率在94.9%～102%之间,相对标准偏差范围为1.2%～4.9%。结论方法简便、快速、准确,能满足鸡蛋中金刚烷胺和氟苯尼考残留量同时分析需要。     

液相色谱-串联质谱法测定茶叶中二氰蒽醌残留量

目的建立液相色谱-串联质谱法(liquidchromatographytandemmassspectrometry,LC-MS/MS)测定茶叶中二氰蒽醌残留。方法茶叶用乙腈(含0.1%甲酸)提取,经固相萃取柱(HC-C18 SPE)净化后采用多反应监测(multiplereactionmonitoring,MRM)模式进行检测,外标法定量。结果目标化合物在一定范围内(0.391～12.5μg/L)线性关系良好,相关系数(r2)大于0.995。样品中二氰蒽醌的定量限(limitofquantification,LOQ)和检出限(limitofdetection,LOD)分别为10.0、5.00μg/kg;不同加标浓度样品10.0μg/kg(LOQ)、20.0μg/kg(2×LOQ)、50.0μg/kg(5×LOQ)的平均回收率为84.1%～103%,相对标准偏差(RSDs)为3.18%～4.62%。25份市售茶叶中均未检出二氰蒽醌。结论该方法简便、快速,准确。各项性能参数均能符合技术规范的要求,已应用于市售茶叶的检测。     

超高效液相色谱-串联质谱法快速测定调味料中5种罂粟壳生物碱残留量

建立超高效液相色谱-串联质谱法(UPLC-MS/MS)测定调味料中吗啡、可待因、蒂巴因、罂粟碱、那可丁5种生物碱含量的分析方法。0.2%甲酸的乙腈提取样品,采用QuEChERS方法处理及净化,经乙酸乙酯-环己烷(2∶8,V/V)脱脂,Waters UPLC HSS T3色谱柱(1.7μm,2.1 mm×100 mm)分离,以含0.1%甲酸10 mmol/L甲酸铵溶液-乙腈为流动相梯度洗脱,电喷雾电离正离子(ESI+)、多反应监测(MRM)模式分析测定,外标法定量。结果表明,5种生物碱5 min内出峰完全,且分离度及各峰型良好。精密度试验结果相对标准偏差(RSD)为0.43%～1.85%,平均回收率为65.7%～108.2%,RSD为1.24%～8.71%。吗啡、可待因的检出限(LOD)和定量限(LOQ)分别为3.0μg/kg、10.0μg/kg;蒂巴因、罂粟碱和那可丁的LOD和LOQ分别为0.6μg/kg、2.0μg/kg。该方法简单、快捷、准确,可用于调味料等食品中罂粟壳生物碱的定性与定量分析。     

液相色谱-串联质谱法测定烟草制品中的羰基化合物

建立了测定烟草制品中8种羰基化合物的液相色谱-串联质谱(LC-MS/MS)方法。以d3-甲醛-2, 4-二硝基苯腙为内标,样品经乙腈萃取后用DNPH将其衍生化反应、过0.45μm有机相滤膜后直接进行LC-MS/MS分析。结果表明:8种羰基化合物在1～80 ng/m L范围内,线性相关系数均≥0.999 0, 3个加标水平的回收率在92.1%～96.3%之间,相对标准偏差(RSD)为2.3%～4.9%。方法的检出限(LOD)和定量限(LOQ)分别为0.14～0.3μg/g (S/N=3)和0.5～1.0μg/g (S/N=10)。该方法准确、灵敏,适合用于烟草样品中羰基化合物的测定。     

液相色谱-串联质谱法测定食品中壬基酚残留

试验旨在建立食品中壬基酚残留的液相色谱-三重四极杆串联质谱检测方法。样品经乙腈提取壬基酚同时除去蛋白质。以Hypersil GOLD C_(18)色谱柱(4.6 mm×50 mm, 1.9μm)分离,流动相为甲醇-水(10︰90, V/V),流速0.35 mL/min,液相色谱-串联质谱仪测定,内标法定量。在该优化条件下,包装饮用水的检出限为0.050μg/kg,定量限为0.100μg/kg, RSD为2.9%～5.6%;其它类食品的检出限均为1.00μg/kg,定量限均为2.00μg/kg, RSD为2.8%～9.4%。典型基质加标水平设定为10, 20和100μg/kg,方法平均回收率为86.0%～114.3%,平均相对标准偏差为2.8%～9.5%(n=6)。该方法前处理简单,灵敏度高,适用于食品中壬基酚残留的准确定性、定量分析。     

Probiotics and prebiotics--perspectives and challenges

Owing to their health benefits, probiotics and prebiotics are nowadays widely used in yogurts and fermented milks, which are leader products of functional foods worldwide. The world market for functional foods has grown rapidly in the last three decades, with an estimated size in 2003 of ca US$ 33 billion, while the European market estimation exceeded US$ 2 billion in the same year. However, the production of probiotics and prebiotics at industrial scale faces several challenges, including the search for economical and abundant raw materials for prebiotic production, the low-cost production of probiotics and the improvement of probiotic viability after storage or during the manufacturing process of the functional food. In this review, functional foods based on probiotics and prebiotics are introduced as a key biotechnological field with tremendous potential for innovation. A concise state of the art addressing the fundamentals and challenges for the development of new probiotic- and prebiotic-based foods is presented, the niches for future research being clearly identified and discussed.     

常用消毒灭菌法及其机理与应用

介绍了采用消毒灭菌方法,有加热消毒法,紫外线辐射法和化学药剂消毒法。常用化学药剂有醛类、含氯消毒剂、醇类消毒剂以及高锰酸钾、生石灰等,阐释了消毒与灭菌两个概念的区别。     

益生素、益生菌与结肠癌

介绍了益生素和益生菌及其作用机理。在动物模型中，有大量的数据证实益生素和益生菌能够预防癌症．而在人体内还没有直接实验证据。它们抑制癌症的确切机理目前尚不清楚，其抑制机理可能是：肠道菌群代谢活动的改变，肠道理化环境的改变，潜在的致癌物质的黏附和降解，肠道菌群的改变、抗癌或抗诱变物质的形成、提高宿主的免疫应答、影响宿主的生理活动以及发酵不能被消化的食物并形成有益代谢产物。     

节能节水型印染助剂和设备的现状

从节能、节水、缩短工艺流程和环保的角度出发，介绍了国内外研制开发的一系列新型节能、节水型印染助剂和染整设备。     

European citizen and consumer attitudes and preferences regarding beef and pork

This paper presents the combined mid-term findings of the consumer research components of two EU Sixth Framework Programme integrated projects concerning meat, ProSafeBeef and Q-PorkChains. The consumer pillar of ProSafeBeef carried out eight focus group discussions in May 2008, in France, Germany, Spain and the UK. Q-PorkChains conducted a large-scale, web-based, consumer survey in January 2008 in Belgium, Denmark, Germany, Greece and Poland. The first project provides a set of qualitative data from a small cohort of focus groups and the second a set of quantitative data from a larger consumer sample. This paper draws together the main findings of both projects and provides a comprehensive overview of European citizens’ and consumers’ attitudes towards and preferences regarding beef and pork. In general, consumers consider meat to be a healthy and important component of the diet. Consumers support the development of technologies that can improve the health attributes of meat products and guarantee eating quality, but they have a negative view of what they see to be excessive manipulation and lack of naturalness in the production and processing of beef products. In the Q-PorkChains study consumer and citizen segments are identified and profiled. Consumer segments were built upon the frequency and variety of pork consumption. The citizen segments were built upon their attitudes towards pig production systems. Overall, the relationship between individuals’ views as citizens and their behaviour as consumers was found to be quite weak and did not appear to greatly or systematically influence meat-buying habits. Future studies in both projects will concentrate on consumers’ acceptance of innovative meat product concepts and products, with the aim of boosting consumer trust and invigorating the European beef and pork industries.     

Heritability and correlations for body condition score and dairy form within and across lactation and age

The objectives of the current study were to investigate the relationship between body condition score (BCS) and dairy form and changes in genetic parameters for BCS and dairy form within and across lactations and age. Body condition score and dairy form were obtained from the Holstein Association USA, Inc. Records were edited to include those cows classified between 24 and 60 mo of age and between 0 and 335 d in milk (DIM). A minimum of 20 daughters per sire and 15 cows per herd-classification visit were required. The dataset consisted of 135,178 records from 119,215 cows. Repeatability, multiple trait, and random regression models were used to analyze the data. All models included fixed effects for herd-classification visit, age within lactations 1, 2, and 3 or higher, and 5th-order polynomials for DIM. Random effects included sire and permanent environment for all models. Random regression models included age at classification nested within sire or DIM and lactation number nested within sire. Genetic variance for both BCS and dairy form was lowest in early lactation and highest in midlactation. Genetic correlations within and across lactations were high. The genetic correlation between DIM 0 in lactation 1 and DIM 305 in lactation 3 was estimated to be 0.77 for BCS and 0.60 for dairy form. The genetic correlation estimate between 30 mo of age at classification and 50 mo of age at classification was 0.94 for both dairy form and BCS. The repeatability models appeared to generate accurate evaluations for BCS or dairy form at all ages and stages of lactation.     

组学技术与果蔬采后质量和安全控制

果蔬可以提供营养, 有利于人类健康, 而果蔬的后熟及其与环境的相互作用会影响果蔬采后的质量和安全。对果蔬生物学过程的了解和掌握是减少果蔬采后损失和保障果蔬采后质量和安全的关键。在过去的10多年, 基于组学技术的系统生物学在了解果蔬后熟及其与环境相互作用的分子机制方面得到了越来越多的应用。本文对此做了细致的总结, 指出了存在的不足, 并提出了未来的发展方向。     

毛霉型低盐速成豆豉工业化生产工艺与设备

本文介绍了毛霉型低盐速成豆豉的工业化生产工艺及生产线的关键设备。     

原花色素及其开发应用

对原花色素的结构、化学特性、制备、分析方法、应用前景作一综述,并重点讨论其生理功能,为在功能性食品、药物、化妆品等领域的深入研究和开发提供参考。     

酚类物质的结构与性质及其与葡萄及葡萄酒的关系

酚类物质是一类大而复杂的化合物。葡萄与葡萄酒中常见的酚类物质可分为类黄酮和非类黄酮两大类，它们是葡萄中重要的次生代谢产物，与葡萄的抗病性、采后生理、贮存、保鲜等密切相关。葡萄酒中的酚类物质来自于葡萄果实、果梗、酵母代谢以及橡木桶，参与形成葡萄酒的味道、骨架、结构和颜色等，对红葡萄酒的特征和质量尤其重要。