利用高效液相色谱-四极杆飞行时间串联质谱研究冻藏鲩鱼中主要单体化合物

采用高效液相色谱-四极杆飞行时间串联质谱(HPLC-Q-TOF-MS)对冻藏鲩鱼肉甲醇提取液中的主要单体化合物进行推导和解析。利用正、负离子两种扫描方式,并依据高分辨质谱提供的准分子离子峰和碎片离子的精确分子质量信息,确证有关物质及其特征碎片离子的分子组成,再通过结合chemspider数据库,最终确定冻藏鲩鱼肉中的36种单体化合物组分,并对每个组分的主要碎片数据进行推导与解析。结果显示:36种单体化合物包括32种含N化合物和4种非含N化合物,32种含N化合物中包括5种氨基酸(ɑ-氨基酸3种)、8种胺类化合物、14种酰胺类化合物、2种硝基类化合物和3种杂环类化合物。采用HPLC-Q-TOF-MS和质谱裂解规律,可推导出鲜活、易腐原料中的单体化合物结构,提高化学成分的鉴定与分析效率,有利于鲜活原料保藏过程中活性成分与新化合物的鉴别与演变推导。     

超高效液相色谱-四极杆/静电场轨道阱高分辨质谱法探究大环内酯类质谱裂解规律

目的 采用超高效液相色谱-四级杆/静电场轨道阱高分辨质谱研究大环内酯类化合物的质谱裂解规律。方法 采用Waters ACQUITY UPLC BEH Shield RP 18(2.1×50 mm,1.7 μm)色谱柱,以甲醇和0.1%甲酸水溶液为流动相进行梯度洗脱,在电喷雾正离子模式下采集数据,采用全扫描和数据依赖的二级扫描模式,根据一、二级质谱离子的精确质荷比推导大环内酯类化合物可能的裂解途径。11种大环内酯类抗生素主要发生糖苷键的断裂。结果 替米考星、吉他霉素、交沙霉素、泰乐菌素和螺旋霉素主要的特征离子碎片为m/z 174.11247、m/z 156.10191以及m/z 116.07060,同时丢失中性分子H2O。琥乙酰红霉素酯、竹桃霉素、泰利霉素、地红霉素、依托红霉素和克拉霉素主要的特征离子碎片为m/z 158.11756、m/z 116.10699以及m/z 98.09643,同时丢失中性分子H2O。结论 该研究提出的质谱裂解规律对快速鉴定和分析复杂体系中大环内酯类化合物具有重要作用。     

基于UPLC-QTOF-MS/MS技术分析荷叶乙酸乙酯相中主要化学成分

采用超高效液相色谱-四极杆飞行时间串质谱技术分析荷叶乙酸乙酯相中的主要化学成分,根据色谱峰的精确分子质量、母离子、碎片离子、质谱裂解规律等信息,结合荷叶中已经鉴定的化合物以及相关参考文献对化合物的结构进行鉴定。从荷叶乙酸乙酯相中共鉴定出40 种化合物,包括27 种黄酮类化合物、6 种酚酸、4 种有机酸、2 种脂肪酸和1 种氨基酸。黄酮类化合物是荷叶乙酸乙酯相中的主要化学成分,主要为槲皮素糖苷、山柰酚糖苷、异鼠李素糖苷和黄酮-3-O-醇类,其次为酚酸。本研究可为荷叶资源在食品加工和功能性食品开发领域的应用提供理论基础。     

基于气相色谱-质谱联用技术的蝎子中脂肪酸与氨基酸的同时提取与分析

为从小分子角度了解蝎子发挥营养及药用功效的物质基础,采用甲基叔丁基醚-甲醇-水体系提取样品,分别通过提取溶剂体系的上层有机相富集全蝎中的疏水化合物,下层水相提取极性小分子。提取物经气相色谱-质谱分析,在非极性组分中检测到30种脂肪酸,70%以上为不饱和脂肪酸;在其极性组分中检测到氨基酸类、有机酸类及糖类等化合物,以氨基酸类化合物为主,占总极性化合物50%以上。这些具有多种生物活性及营养价值的不饱和脂肪酸、氨基酸可能是全蝎发挥药效及食疗作用的物质基础。与文献报道全蝎中脂肪酸组成以饱和脂肪酸为主不同,检测到的脂肪酸主要是油酸和cis-9,cis-12-亚油酸,其次为棕榈酸和硬脂酸。在全蝎中发现的游离氨基酸共有13种蛋白质氨基酸和3种非蛋白质氨基酸,包括7种必需氨基酸(赖氨酸除外)和6种药效氨基酸。该工作为进一步研究全蝎的药用及食用价值提供了物质基础。     

运用RPLC-ICP-MS对富硒酵母中硒形态分析

分析了硒酵母片中硒的存在形态。采用蛋白酶解法水解酵母片中的蛋白质部分,并提取出构成酵母蛋白质的各种氨基酸成分,利用反相离子对色谱与电感耦合等离子质谱联用方法对其中的含硒氨基酸进行测定,确定含硒氨基酸种类。通过与含硒标准化合物在色谱柱上的保留时间比较,确定蛋白酶解液中主要的含硒氨基酸为硒代蛋氨酸。蛋白酶解提取手段和反相离子对色谱与电感耦合等离子质谱联用的检测技术,适合于酵母中的硒形态分析。     

基于超高效液相色谱-四极杆/静电场轨道阱高分辨质谱技术研究全氟化合物质谱裂解规律

目的 采用超高效液相色谱-四级杆/静电场轨道阱高分辨质谱研究全氟化合物的质谱裂解规律。方法 采用Thermo Hypersil GOLD aQ色谱柱（100 mm×2.1 mm,1.9 μm）,以甲醇和0.1%甲酸水溶液为流动相进行梯度洗脱,在电喷雾负离子模式下采集数据,采用全扫描和数据依赖的二级扫描模式,根据一、二级质谱离子的精确质荷比推导全氟化合物可能的裂解途径。 结果 全氟磺酸类化合物主要发生CC键和CS键断裂,产生特征碎片[·C3F6-SO3]- m/z 229.94和[SO3]- m/z 79.95;全氟羧酸类化合物首先丢失中性分子CO2,产生[M-O-CO2]-碎片离子,继而发生不同数量的CC键断裂,产生m/z 218.98、168.98、118.99等特征碎片离子。结论 该研究提出的质谱裂解规律对快速鉴定和分析复杂体系中全氟化合物具有重要作用。     

基于UHPLC-LTQ-Orbitrap高分辨质谱的黄花菜中化学成分快速鉴定及裂解途径分析

采用超高效液相色谱-线性离子阱-静电场轨道阱(UHPLC-LTQ-Orbitrap)高分辨质谱法分析黄花菜中的化学成分。在负离子模式下,采用Hypersil Gold AQ RP-C18色谱柱(100 mm×3.0 mm,1.9μm),以0.1%甲酸水溶液和0.1%甲酸乙腈溶液为流动相梯度洗脱,流速0.3 mL/min;用LTQ-Orbitrap高分辨质谱解析多级质谱数据,并对成分进行定性分析。根据液相保留时间、紫外吸收、精确分子质量数据、多级质谱碎片离子和相关文献报道,从黄花菜中共鉴定出27个组分。其中,酚酸类化合物12个,黄酮醇类15个及其它类1个。本方法可高效、快速、灵敏、全面地分析黄花菜的化学成分,可实现酚酸及黄酮类不同化合物的鉴别,为探讨黄花菜的药效物质基础和类似化合物的结构鉴定提供理论依据。     

采用GC×GC-TOF-MS分析酱香型白酒缺陷酒挥发性风味物质

采用顶空固相微萃取结合全二维气相色谱-飞行时间-质谱（GC×GC-TOF-MS）技术解析酱香型白酒缺陷酒,并初步推断导致酒体缺陷的物质种类。对酱香型白酒盐菜味缺陷酒中共鉴定出的415种挥发性组分进行归类,并着重分析了16种含硫化合物、20种含氮化合物、17种呋喃类化合物以及33种萜烯类化合物对白酒风味的贡献。结果表明,萜烯类、呋喃类以及含氮化合物是酱香型白酒重要的风味物质及功能化合物,而鉴定出的含硫化合物多具有低阈值且给白酒带来不愉快气味的特征,很有可能是酱香型白酒产生缺陷的重要物质来源。酱香型白酒缺陷酒中挥发性物质的解析对缺陷酒中异嗅物质的准确定性和定量研究具有指导意义。     

高效液相色谱-四级杆飞行时间质谱法鉴别白酒中羧酸

利用高效液相色谱-四级杆飞行时间质谱联用(LC-QTOF)技术,主要分析白酒中的羧酸类化合物。根据化合物质荷比、同位素相对丰度、同位素比例等的相似度,初步确定白酒中的羧酸化合物的目标离子,并以各羧酸在目标离子扫描模式下的断裂规律、二级质谱碎片离子为依据,对应解析、定性白酒中的羧酸。该方法共定性分析出白酒中46种羧酸成分,其中包括5个α-羟基羧酸,3个杂环羧酸,4个芳香羧酸,3个二羧酸,5个酚酸,26个一元羧酸。研究结果表明,该方法能有效地分辨白酒中相同分子式下的酸酯成分,解析白酒中的羧酸成分。     

基于超高效液相色谱-四极杆-飞行时间高分辨质谱分析酸橙果实中的生物活性成分

应用超高效液相色谱-四极杆-飞行时间高分辨质谱结合靶向和非靶向筛查方法系统分析鉴定了6个酸橙果实品种的不同部位(果皮、果肉、果汁)的生物活性物质.根据化合物的精确分子质量、质谱裂解规律、碎片离子信息,结合数据库匹配、标准品比对并参考相关文献对化合物结构进行鉴定.该实验共鉴定了84种生物活性成分,包括44种类黄酮、8种酚...     

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.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

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