葡萄籽超微粉中白藜芦醇的HPLC检测

采用超声法提取葡萄籽超微粉中的白藜芦醇,用高效液相色谱法测定葡萄籽超微粉中的白藜芦醇,色谱条件为:固定相为shim-park VP-ODS C_(18)(250mm×4．6mm I．D)柱,流动相为28%乙腈水溶液进行等压洗脱,流速1．0 mL/min,检测波长为305nm,柱温为30℃,进样量20μL。结果表明:白藜芦醇在2．0μg/mL～10．0μg/mL的范围内具有良好的线性关系,相关系数γ=0．9993;平均回收率为97．13%, RSD为2．113%。     

同步荧光法测定红葡萄酒中白藜芦醇含量

建立了一种应用同步荧光检测红葡萄酒中白藜芦醇的新方法,系统研究了检测条件对白藜芦醇荧光强度的影响。该方法的回归方程为Int(荧光强度)=19.70×Conc(浓度μg/mL)+13.98,相关系数r=0.9987。白藜芦醇产生的荧光强度与浓度在0～1.96×10-5mol/L的范围内具有良好的线性关系,检测限为8.14×10-10mol/L。     

同步荧光法分析红葡萄酒中微量白藜芦醇含量的研究

建立了一种应用同步荧光检测红葡萄酒中白藜芦醇的新方法,系统研究了检测条件对白藜芦醇荧光强度的影响。该方法的回归方程为Int(荧光强度)=19.70×Conc(浓度μg/mL)+13.98,相关系数r2=0.9987。白藜芦醇产生的荧光强度与浓度在0mol/L～1.96×10-5mol/L的范围内具有良好的线性关系,检测限为8.14×10-10mol/L。     

液相色谱测定葡萄酒中白藜芦醇含量的方法研究

建立了HPLC测定葡萄酒中白藜芦醇含量的方法,采用色谱柱:THERMO C18(4.6×25 mm,5μm),检测波长:30 nm,流量:1.0 m L/min,进样量:20μL,流动相水-乙腈为65∶35。结果表明:白藜芦醇在0~5μg/m L范围内呈现良好的线性关系,Y=183 298X+15 201.8(0~5μg/m L)(R2=0.999 6)。平均回收率99.7%,RSD=0.75%。本方法简单,快速、准确、重现性好,可以用作葡萄酒中白藜芦醇的含量测定,为评价葡萄酒的品质提供依据。     

桑椹中白藜芦醇及白藜芦醇苷测定方法的建立及含量比较

目的：建立同时测定桑椹中白藜芦醇(Res)和白藜芦醇苷(PD)的HPLC 方法,探索Res 和PD 在桑椹成熟过程中的变化规律,以及两者在不同品种中的含量差异。方法：phenomenex C18 色谱柱(150mm × 4.6mm,4μm),甲醇- 水为流动相梯度洗脱,检测波长305nm,流速0.8mL/min,测定处于不同成熟期的红果2 号桑椹以及红果1号、西农1 号、嘉陵30 号1 系、嘉陵30 号2 系成熟桑椹的Res 和PD 含量。结果：Res 在进样量0.5～50μg/mL、PD 在2～100μg/mL 范围内均呈良好的线性关系,加标回收率分别为99.0%、98.28%,RSD 分别为3.86%、1.18%;在桑椹发育全程中PD 的含量始终高于Res,桑椹中的Res 和PD 含量均为红果中期最高,紫果时下降;5 个桑椹品种中,西农1 号红果的总白藜芦醇含量最高,达94.5μg/g。结论：该方法能快速准确地测定Res 和PD 的含量;桑椹不论红果还是紫果,白藜芦醇含量均较高,其最佳采摘期为红果刚转紫时。     

HPLC法测定葡萄酒中白藜芦醇的基础性研究

利用高效液相色谱法 (HPLC)测定葡萄酒中的白藜芦醇 (resveratrol) ,测得相对标准偏差为 1.8%～4 .4 % ,回收率为 95 .4 %～ 10 2 .9% ,具有简便快捷、选择性好、准确度高之特点。最佳分离条件为 :流动相为含 4 0 %体积乙腈的水溶液 ,流速为 0 .6mL/min ,柱温为 2 5℃ ,检测波长为 30 6nm ,进样量 2 0uL。     

微波消解-原子吸收分光光度法测定保健食品中铝元素含量

目的建立微波消解-石墨炉原子吸收分光光度法测定固体、液体和软胶囊3种基质的保健食品中铝元素含量的分析方法。方法前处理方法经实验确定为5 mL硝酸和2 mL过氧化氢(30%,V:V)双溶剂消解,经微波消解仪消解,采用石墨炉原子吸收分光光度测定保健食品中铝元素的含量。结果铝元素在0～500μg/mL的浓度范围内线性关系良好,相关系数为0.998;铝元素的检出限为0.24 mg/kg;回收率为81.2%～98.7%;相对标准偏差小于3.2%(n=6)。结论该方法操作简单、灵敏度高、检出限低,满足保健食品中铝元素含量的测定。     

花生中白藜芦醇和白藜芦醇苷的提取及含量测定

建立高效液相色谱紫外法同时测定花生中白藜芦醇和白藜芦醇苷含量的方法。以85%乙醇水溶液为提取剂,采用直接超声提取、高速匀浆提取和固相萃取3种不同提取方法处理花生样品,对提取剂使用量和提取方法进行比较研究,高效液相色谱法进行含量测定。结果表明:当提取剂使用量为40mL时,固相萃取提取法效果最好,白藜芦醇的加标回收率为96. 00%～109. 55%,相对标准偏差(RSD)为1. 64%～2. 17%,检出限为0. 016mg/kg;白藜芦醇苷的加标回收率为91. 82%～104. 67%,相对标准偏差(RSD)为1. 73%～2. 81%,检出限为0. 052mg/kg。测定的山东省210个花生样品中白藜芦醇含量为0. 17～11. 39mg/kg,含量最低的是花育22,最高的是白玉品种;白藜芦醇苷含量为0. 22～1. 44mg/kg,含量最低的是春甜,最高的是山花9号品种。该方法适合于花生样品中白藜芦醇和白藜芦醇苷含量的测定。     

QuEChERS/气相色谱三重四级杆质谱法测定枸杞籽油中多环芳烃类物质

建立了同时检测保健食品枸杞籽油中16种多环芳烃(PAHs)的QuEChERS/气相色谱三重四级杆质谱(GC-MS/MS)方法。样品(0. 5 g)经3 mL乙腈提取2次,采用含200 mg PSA和100 mg C18吸附填料粉进行净化,净化后采用GC-MS/MS进行分析测定。结果表明:在优化条件下,16种PAHs分离度良好,在1. 0～200 ng/mL范围内线性关系良好;回收率为60. 04%～119. 00%,RSD在2. 92%～13. 03%之间;检出限在0. 2～3. 5μg/kg之间,定量限在0. 7～11. 5μg/kg之间。该方法数据可靠、简便快速、灵敏度高,适合保健食品枸杞籽油中多环芳烃的测定。     

基于氨丙基SiO2微球固相萃取-高效液相色谱法测定花生中白藜芦醇

目的 建立一种固相萃取-高效液相色谱法测定花生中白藜芦醇的含量分析方法。方法 样品用85%乙醇提取,用氨丙基SiO2微球材料填充固相萃取净化小柱富集,乙醇作为淋洗溶液,吹干后用0.2 mL甲醇定容检测。采用 C18色谱柱,以乙腈和水为流动相等度洗脱分离,检测波长为306 nm检测。结果 该方法在0.1~10 μg/g的范围内,白藜芦醇线性关系良好(r2＞0.999),检出限为 0.017 μg/g,定量限为 0.056 μg/g;加标回收率为90.4%～107.2%,相对标准偏差为1.3%～8.3%。运用该方法对30份花生样品检测,其白藜芦醇含量范围在73.24～548.51 μg/kg之间。结论 该方法灵敏度高、重复性好、成本低廉,且操作简单、快速,满足花生中白藜芦醇定量分析的要求。     

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