重组酶介导等温扩增技术快速检测牛肉及 牛肉制品中的牛源性成分

目的建立重组酶介导等温扩增技术快速检测牛肉及牛肉制品中牛源性成分的方法。方法应用重组酶聚合酶等温扩增技术(recombinase polymerase amplification,RPA),根据牛源性线粒体细胞色素b(Cytb)基因序列设计筛选了一对可用于扩增的引物,建立基于重组酶介导的等温扩增技术检测方法,并对该方法进行扩增温度、特异性和灵敏性验证。结果 40℃等温扩增条件下,所设计的引物的特异性为100%,该检测方法的灵敏性可达0.1 ng/μL。结论本研究成功建立了牛源性肉制品的等温扩增方法,该方法快速简便,具有较高的特异性和灵敏性,适用于市售生鲜肉制品及加工肉制品中牛源性成分的鉴定。     

重组聚合酶等温扩增技术快速鉴别玛卡及其制品的研究

应用重组聚合酶扩增技术(recombinase polymerase amplification,RPA),根据玛卡特异性基因defensin序列设计筛选了1对可用于扩增的引物,建立了玛卡及其加工产品特异性源性成分的RPA检测方法。该方法具有较高的灵敏性,检测灵敏度达到0.1 ng/L以上,操作方便,可以在室温条件下完成反应,检测可在0.5 h内完成,极大缩短了检测时间,适用于市场上玛卡及其制品的快速鉴别。     

重组酶恒温扩增技术在动植物源成分分析中的应用与研究进展

近年来,以肉制品和转基因农作物掺假掺杂为主的动植物源成分分析成为食品安全研究及监管领域关注的重点,对于靶向物检测水平的要求也逐渐提高。重组酶恒温扩增技术是一种具有实用性和发展前景的检测技术,包括重组酶聚合酶恒温扩增（RPA）和重组酶介导的恒温扩增（RAA）等,因其具备快速便捷、灵敏度高、特异性强等优点,广泛应用于动植物源成分检测及各类分析研究领域。本文综合近年来国内外相关研究,归纳了现有分析检测方法,从引物探针设计、外界影响因素、反应装置和检测途径4个方面对RPA/RAA技术的特点及应用进行概述,并对该领域发展趋势进行展望,为动植物源成分检测方法的完善和重组酶恒温扩增技术的应用提供参考。     

双拖尾重组聚合酶恒温扩增技术结合核酸杂交侧流条快速检测牛肉中的鸡、鸭、猪源性成分

目的 建立双拖尾重组聚合酶恒温扩增(recombinase polymerase amplification,RPA)结合核酸杂交侧流条(nucleic acid hybridization-lateral flow strip, NAH-LFS)快速检测牛肉中鸡源、鸭源、猪源性成分的可视化检测技术。方法 采用多重双拖尾RPA技术与NAH-LFS相结合,对鸡、鸭、猪线粒体D环区域设计特异性拖尾RPA引物,扩增出双拖尾的RPA产物。鸡、鸭、猪3个物种RPA产物的拖尾序列分别与红、黄、蓝3种颜色的金纳米探针和侧流条上的检测探针杂交。结果 鸡、鸭、猪3个物种RPA产物与探针杂交后形成肉眼可见的红、黄、蓝3色条带,整个RPA扩增(15 min)和侧流条检测(5 min)过程在20 min内即可完成。该方法对牛肉中鸡、鸭、猪肉的检出限达0.01%,且仅对鸡、鸭、猪肉DNA有特异性,与其他10个物种的DNA均无交叉反应。采集50份市售牛肉样品,使用该方法进行真实性检测:10份牛肉干、10份生牛肉、10份酱牛肉中未检测出其他动物源性成分, 10份牛肉馅料中检测出1份含猪源性成分, 10份牛肉片中检测...     

重组酶等温扩增技术快速检测对虾中的白斑综合征病毒

摘 要: 目的 针对对虾中白斑综合征病毒(White spot syndrome virus, WSSV),分别建立基于国外专利技术的重组酶聚合酶扩增(Recombinase polymerase amplification, RPA)方法,基于国内专利技术的重组酶介导等温扩增法(Recombinase-aided amplification, RAA) 方法,并对两种方法进行比较。方法 应用重组酶等温扩增技术在恒温(39℃)条件下完成扩增反应的优势, 调整反应体系中模板DNA和探针浓度, 优化WSSV病毒RPA和RAA两种方法的反应体系, 建立了可靠稳定的等温扩增RPA和RAA快速检测方法,比较了两种方法的特异性、灵敏度、扩增效率和稳定性。。结果 所建立的荧光RPA和RAA方法在恒温39 ℃的条件下特异性检测WSSV, 检测构建质粒DNA的灵敏度可达到1.0×106 copies/μL, 检测实际感染阳性样品的灵敏度可达到1.31×101 pg/μL; RPA方法的扩增线性曲线拟合度R2=0.9970, 扩增效率为 98.50%;RAA方法的扩增线性曲线拟合度R2=0.9910, 扩增效率为 98.50%。 结论 所建立的基于重组酶等温扩增技术的RPA和RAA方法,特异性好,对于质粒和阳性样品检测灵敏度一致,扩增效率一致,具有很好稳定性。适用于水产品养殖及生产加工和通关口岸进口虾类产品中WSSV病毒的现场快速筛查防控。     

三重LAMP法检测阿胶中驴、马和猪源性成分

为能快速检测阿胶中驴、马、猪源性成分,建立了三重环介导等温扩增(LAMP)检测方法。针对驴、马、猪线粒体基因的保守区域,设计并筛选出3套LAMP特异性引物。通过优化反应条件,建立三重LAMP方法,将检测为阳性的产物进行酶切法鉴定,判断样本中驴、马或猪源性成分。驴、马和猪的检测限分别为7.9×10^–3、1.36×10^–3 ng和8.5×10^–2 ng。结果表明该检测方法操作简便、特异性强、灵敏度高,适合于市场阿胶真伪鉴别与驴、马和猪源性成分的鉴定。     

水产品中哈维氏弧菌等温快速检测方法优化及比较

目的 基于核酸等温扩增技术,建立并优化哈维氏弧菌(Vibrio harveyi)荧光法和可视化环介导恒温扩增(Loop-mediated isothermal amplification,LAMP)、重组酶聚合酶扩增(Recombinase polymerase amplification,RPA)快速检测方法。方法 选择哈维氏弧菌toxR基因为特异靶标序列,分别设计了2组LAMP引物、3组RPA引物,对引物进行筛选,优化建立了荧光法LAMP、可视化LAMP、普通RPA三种等温扩增方法,对三种方法的特异性和灵敏度进行比较,并用模拟污染样本验证检测实际样品的灵敏度。结果 基于快速提取的哈维氏弧菌基因组DNA,本文所建立的荧光法LAMP、可视化LAMP、普通RPA三种等温扩增方法均具有良好的特异性,与同属及近属的细菌没有交叉反应。三种方法的灵敏度分别为5.27 fg/μL(1.99 fg/μL~0.93 pg/μL,95%CI),0.11 ng/μL,1.07 pg/μL;荧光LAMP和普通RPA对模拟污染样本的灵敏度分别为7 CFU/mL和97 CFU/mL。结论 本文建立优化的三种等温快检方法结果准确、操作简单,扩增效率和灵敏度优于文献报道的同类方法,提高了哈维氏弧菌现场快速检测水平。     

利用重组酶聚合酶扩增技术快速鉴定肉及肉制品中的猪源性成分

根据家猪线粒体细胞色素b的核苷酸序列设计和筛选实时荧光定量重组酶聚合酶扩增(Real time recombinase polymerase amplification,real-time RPA)反应所需的引物和探针,优化反应参数(Mg~(2+)和引物浓度),建立了一套利用real-time RPA技术进行肉及肉制品中猪源性成分的鉴定方法。应用此方法可以检测出肉及肉制品中低至0.2%的猪源性成分,且能够在恒温的条件下(40℃)15min中内完成反应,克服了传统聚合酶链式反应(Polymerase chain reaction,PCR)技术需要精密温度循环控制设备的局限性,是一种新型、简单、高效的检测方法,对实现快捷便携式的猪源性成分鉴定检测具有重要的意义。     

重组酶聚合酶等温扩增技术在食品安全检测领域的应用

重组酶聚合酶等温扩增技术(recombinase polymerase amplification,RPA)是一种新型核酸等温扩增技术。该技术相对于PCR等其他核酸体外扩增技术具有灵敏度高、特异性强、检测时间短、操作简便等特点。RPA技术在常温下即可进行等温扩增,其最适温度在37～42℃,RPA技术可在简单设备甚至恶劣环境对核酸的进行快速扩增,结合侧流层析技术荧光检测装置可对检测结果进行定性定量分析。文章综述了RPA技术的原理,操作条件及其在食源性病毒、食源性致病菌、动物源性检测及转基因食品检测等方面的应用,为该技术进行更加深入和广泛的研究提供参考。     

基于双拖尾重组聚合酶恒温扩增技术的核酸杂交试纸条快速检测驴肉中的马源性成分

目的：建立快速、操作简单、价格相对低廉的驴肉中马源性成分快速可视化检测技术。方法：采用双拖尾重组聚合酶恒温扩增技术(RPA)与核酸杂交试纸条相结合。针对马线粒体细胞色素b(cytb)基因设计RPA引物,引物包含3个功能区域,特异性绑定区域用于RPA扩增反应,spacer 9用于终止聚合酶的扩增,单链拖尾区域用于与试纸条上的探针杂交。这对特殊引物使RPA扩增子带有两个单链拖尾序列,这两个单链拖尾序列可以特异性地被金纳米探针和试纸条上的检测探针识别并捕获,形成一条肉眼可见的红色条带。整个扩增(15 min)和检测(5 min)过程在20 min即可完成,无需复杂的设备,仅需要一台数字化水浴锅。为进一步验证该方法的实际应用性能,对市面上的20份驴肉产品进行测定,并采用PCR(Polymerase Chain Reaction,PCR)结合琼脂糖凝胶电泳的方法进行验证。结果：该方法对马肉的检测限达到0.01%,且仅对马肉核酸有特异性扩增,与其他8个物种的核酸均无交叉反应,20份驴肉样品中有2份存在马源性成分。结论：该方法特异性强、灵敏度高,可实现驴肉中马源性成分的可视化快速检测。     

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.     

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.     

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.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the     

Chinese CTP Market

According to Printing and Printing Equipment Industries Association of China（PEIAC）＇s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.     

Preparatory Work of Print China 2015 is Going Smoothly

正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press