植物油DNA的高效提取方法研究

针对植物油中DNA含量极低、DNA序列片段短、破坏严重的特点,以食用植物油为原料,旨在建立一种从植物油中稳定、高效提取DNA的方法。实验采用硅膜吸附柱法提取植物油基因组DNA,PCR扩增其相应内源基因进行质量鉴定,再针对通用的外源基因CaMV35S启动子进行PCR、LAMP和实时荧光PCR检测对该方法进行评价。结果表明:该方法提取的DNA质量可靠,采用PCR、LAMP和实时荧光PCR技术成功地检测出了植物油中的CaMV35S启动子。因此,硅膜吸附柱法提取的植物油DNA可以作为PCR、LAMP、实时荧光PCR扩增模板用于转基因成分的检测,该方法经济、稳定、安全,为植物油的基因检测奠定了基础。     

改良LAMP法检测转基因作物

目的 建立简易的可视化环介导等温扩增(LAMP)检测转基因作物的方法。方法 通过一对特异的能识别一段正义链和一段反义链的内引物和一对链置换引物, 在Bst DNA聚合酶作用下, 以等温条件实现对外源转基因成分的扩增, 反应液和高浓度的显色液SYBR GREENⅠ同时置于特殊设计的反应管中, 反应后可实现闭管可视化检测。结果 对转基因作物中常见的外源基因元件胭脂碱合成酶终止子(T-NOS)和烟草花叶病毒35S启动子(P-CaMV35S)进行了LAMP检测。T-NOS LAMP对大米品系BT63, 玉米品系BT11, MON810, 大豆品系GTS40-3-2的检测结果呈阳性, P-CaMV35S LAMP对大米品系BT63, 玉米品系BT11, MON810, MON863, 大豆品系GTS40-3-2的检测结果呈阳性, 二者对非转基因大米, 玉米, 大豆的检测结果均呈阴性。上述结果表明, 本文中建立的T-NOS 和P-CaMV35S LAMP检测方法特异性高。另外, 通过对大豆品系GTS40-3-2模拟样品的检测, 证明T-NOS LAMP能检出转基因成分含量为0.5%的样品, P-CaMV35S LAMP能检出转基因成分含量为0.1%的样品, 检测灵敏度较高。结论 改良LAMP法灵敏度高, 特异性好, 能用于快速初筛转基因作物。     

实时浊度LAMP法检测豆制品中转基因成分

通过设计转基因大豆内源基因(Lectin)、外源基因NOS和2个转基因大豆品系(GTS 40-3-2,MON89788)特异性LAMP引物,建立快速检测转基因大豆以及鉴定转基因大豆品系的LAMP体系,并选取国内豆制品利用CTAB法进行DNA提取,并针对上述基因进行PCR和LAMP扩增的对比,建立起了检测大豆制品中转基因成分的定性的LAMP方法。结果表明:4个LAMP方法均有较好的特异性,除了NOS、GTS 40-3-2的检测限为0.1%外,其他LAMP方法的灵敏度为0.01%,均能满足实际检测要求;在实时浊度LAMP法检测大豆制品转基因成分的鉴定中,传统的CTAB法能成功提取大豆粗加工制品的DNA,且DNA纯度能够进行核酸扩增反应。利用转基因外引物进行的普通PCR结果与实时浊度LAMP结果是一致的,说明建立的转基因实时浊度LAMP检测方法有很好的准确性。     

花椰菜花叶病毒CaMV 35S启动子LAMP检测方法的建立

针对花椰菜花叶病毒(CaMV)35S启动子的保守序列设计特异性引物,并进行条件优化,建立CaMV35S启动子的LAMP检测方法。该方法具有良好的特异性,检测灵敏度可达0.002%。对80份各类植物及其加工品进行检测,检测结果与实时荧光PCR法完全相符。CaMV35S启动子的LAMP检测方法,在检验检疫行业和食品加工业具有广阔的应用前景,对于加强转基因产品检测监管,促进进出口贸易具有重要意义。     

环介导恒温扩增快速检测植物油中掺假地沟油方法的建立

以植物油中不应存在动物源性成分为鉴定依据,建立食用植物油中掺假地沟油的环介导恒温扩增(Loop-mediated isothermal amplification,LAMP)快速检测方法,以动物线粒体DNA为检测靶标,根据脊椎动物线粒体基因组高度保守序列设计了两条外引物(F3、B3)和两条内引物(FIP、BIP),采用LAMP实时荧光法和染色法对扩增产物进行比较分析,对甜菜碱和Bst DNA聚合酶(Bst DNA polymerase)量进行了优化,并进一步评价方法的特异性、灵敏度和稳定性。结果表明,在1.6 μmol/L内引物(FIP和BIP),0.2 μmol/L外引物(F3和B3),6 mmol/L MgSO₄,1.6 mmol/L dNTP,10×Thermo pol Buffer,8 U Bst DNA聚合酶,扩增温度为65℃,扩增时间为1 h的优化条件下,能够一次同时扩增出牛、羊、猪和鸡等脊椎动物DNA序列,检出植物油中最低含量为0.01 ng/μL的动物源性DNA,优化后的LAMP方法特异性好,仅能扩增出动物源性DNA序列、重复性好、稳定性高,可用于油脂中动物源性成分的检测,为油脂鉴伪和地沟油的鉴别提供一种稳定、高效、适应性强的现场快速检测技术。     

食用植物油中DNA提取和基因检测研究进展

为了保障食用植物油的质量安全,基于分子生物学理论建立的分析方法以其准确、快速、操作简单和灵敏度高的特点广泛应用于食用植物油的转基因成分和掺假检测。从DNA含量极少且完整度较低的食用植物油中提取到高质量DNA是影响基因检测成败的关键因素。通过对食用植物油中DNA的不同提取方法和基因检测方法进行综述,对比了各种方法的优缺点,展望了该领域的发展趋势。     

FTA滤膜与环介导等温扩增技术结合快速检测消毒乳中的蜡样芽孢杆菌

目的:建立环介导等温扩增技术(LAMP)快速检测蜡样芽孢杆菌的方法.方法:根据公布的蜡样芽孢杆菌溶血素基因的hblA基因的保守序列设计引物,将FTA滤膜提取DNA与LAMP法相结合,检测蜡样芽孢杆菌和人工污染蜡样芽孢杆菌的消毒乳.结果:LAMP方法检测灵敏度高,蜡样芽孢杆菌的检出限为4.4 cfu/mL,比PCR检测灵敏度高10倍;人工污染消毒乳中蜡样芽孢杆菌的检出限为57 cfu/mL.LAMP扩增可在20 min内完成,对消毒乳中蜡样芽孢杆菌的检测(包括DNA提取、LAMP和电泳)可在2 h内完成.结论:初步建立LAMP检测蜡样芽孢杆菌的快速检测方法.该方法灵敏度高、特异性好、耗时短.为食品中蜡样芽孢杆菌快速检测构建了一个技术平台.     

豆腐中转基因大豆成分的检测

目的探索适合豆腐样品的DNA抽提方法并采用实时荧光聚合酶链反应(PCR)技术对豆腐试样中的转基因大豆成分进行检测。方法分别采用CTAB和SDS配制抽提缓冲液提取18个豆腐样品中的DNA,针对转基因大豆都含有大豆内源基因lectin及共同元件CaMV35S启动子、nos终止子及epsps基因进行实时荧光PCR扩增。结果 SDS法比CTAB法提取的豆腐DNA质量更好;18个豆腐样品均检测到了lectin,其中有2个样品检测到了CaMV35S启动子的荧光信号,4个样品检测到了nos终止子的荧光信号,所有样品均未扩增出epsps基因。结论 SDS法比CTAB法更适合于抽提豆腐样品的DNA,提取到的DNA可用于实时荧光PCR法检测豆腐内源基因和外源基因。     

大豆异黄酮中转基因大豆成分检测研究

利用含有35S启动子、NOS终止子片段的质粒,确定相应检测方法的灵敏度为15个拷贝和150个拷贝;采用扩增CaMV35S启动子的2对引物、扩增NOS终止子的2对引物、扩增EPSPS目的基因的1对引物,对大豆异黄酮样品中转基因成分进行了检测,结果均扩增出了特异性片段,且测序结果正确。     

酸乳中葡糖杆菌的LAMP检测方法研究

为了给酸乳生产企业提供一种快捷、简便、灵敏的葡糖杆菌的LAMP检测方法,本研究选取葡糖杆菌属的模式菌株氧化葡糖杆菌为代表菌株。根据Gen Bank中公布的氧化葡糖杆菌的16S r RNA(X73820)基因的强特异性序列设计四条引物,优化引物、Mg2+、温度等反应条件,建立了环介导等温扩增技术检测酸乳中葡糖杆菌的方法。对该方法的特异性和灵敏度进行评价,并与PCR方法的灵敏度进行比较。结果显示,该组引物的特异性强,对反应产物进行酶切分析,酶切产物的片段与理论值相符;该LAMP方法检测纯菌的灵敏度为7.5×101 CFU/m L,是PCR检测方法的10倍;用纯菌液对酸奶进行人工污染,提取模拟变质酸奶的DNA进行LAMP扩增,其最低检出限为7.5×102 CFU/m L。综上所述,本研究建立的LAMP检测方法特异性强、灵敏度高,耗时短,实现了对葡糖杆菌的快速检测,在食品检测行业具有很好的应用前景。     

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