高效液相色谱法测定不同产地湘莲中荷叶碱、 莲心碱、芦丁的含量

目的建立高效液相色谱法同时测定湘莲中荷叶碱、莲心碱、芦丁的方法。方法在酸性条件下超声提取3种待测组分。色谱条件如下:C_(18)(250 mm×4.6 mm,5μm)色谱柱;流动相:甲醇-0.1 mol/L乙酸铵(用乙二胺调节pH值至7.5~8.0)(55:45,V:V);流速:1.0 m L/min;检测波长:275 nm;柱温30℃;进样量10μL。结果荷叶碱、莲心碱、芦丁分别在7.636~152.7μg/mL(r~2=0.9999,n=5)、7.543~150.9μg/mL(r~2=0.9995,n=5)、7.543~150.9μg/mL(r~2=0.9998,n=5)范围内线性关系良好,加标回收率为96.9%~100.5%之间,相对标准偏差(relative standard deviation,RSD)为1.1%~1.4%。结论该法同时测定湘莲中荷叶碱、莲心碱、芦丁,简单快速,定量准确,可以为评价不同产地湘莲功效成分提供参考。     

高效液相色谱法检测保健食品中的番茄红素

目的建立高效液相色谱法测定保健食品中番茄红素的分析方法。方法用含有0.1%2,6-二叔丁基-4-甲基苯酚抗氧化剂的甲醇:二氯甲烷(10:90,V:V)作为提取溶液。通过Agilent Eclipse XDB-C_(18)(4.6 mm×250mm,5μm)色谱柱;甲醇:乙酸乙酯(85:15,V:V)作为流动相,二极管阵列检测器,检出波长475 nm,色谱柱温25℃,流速1.0 mL/min,进样体积10μL,作为检测条件。结果番茄红素在0~200μg/mL范围内线性良好,相关系数r=0.9995,最低检出限为0.0815μg/mL,平均回收率在89.7%~109.8%之间,RSD为8.4%。结论本方法可以准确、快速地检测保健食品中的番茄红素。     

高效液相色谱法测定槟榔中阿斯巴甜的含量

目的建立高效液相色谱法检测槟榔中阿斯巴甜的含量的分析方法。方法槟榔去除卤水及内层纤维后,以磷酸-水溶液(pH=2)为提取液、采用超声法提取槟榔中阿斯巴甜。提取液经Agilent ZORBAX SB-C_(18)(4.6 mm×250 mm,5μm)色谱柱分离,以乙腈-10 mmol/L KH2PO4水溶液(pH=3.5)(14:86,V:V)为流动相,流速为1 mL/min,采用紫外检测器在210 nm检测波长下对阿斯巴甜含量进行测定。结果阿斯巴甜在4.444~222.2μg/mL范围内呈现良好的线性关系,检出限为0.22μg/mL,精密度为0.17%,在3个加标水平下的平均回收率为99.80%。结论本提取方法易于操作、提取率高且稳定性良好,可用于槟榔中阿斯巴甜的提取;本检测方法具有线性范围广、灵敏度高、快速、准确等优点,适用于槟榔中阿斯巴甜的含量测定。     

固相萃取-液相色谱-串联质谱法测定鸡蛋中小檗碱残留量

目的建立固相萃取-液相色谱-串联质谱(liquidchromatography-tandemmassspectrometry,LC-MS/MS)测定鸡蛋中小檗碱残留量的检测方法。方法样品经80%(V/V)乙腈溶液提取,经过混合阳离子(mixed-mode,strongcation-exchange,MCX)固相萃取柱净化。采用0.1%甲酸(V/V)-甲醇溶液(A)和0.1%甲酸-5 mmol/L乙酸铵溶液(B)进行梯度洗脱,采用正离子模式,多反应监测,基质匹配外标法定量分析。结果小檗碱进样浓度在2～100ng/mL范围内与峰面积呈良好的线性关系(r~2=0.999);方法检出限和定量限分别为0.5和1.0μg/kg;在1.0、2.0、10.0μg/kg3个添加水平下,回收率在62.2%～108.3%之间,相对标准偏差为5.6%～9.8%(n=6)。结论本方法简便、准确、快速、灵敏,适用于鸡蛋中小檗碱残留量的检测。     

超高效液相色谱-三重四极杆串联质谱法同时测定槟榔籽中四种生物碱含量

目的:采用超高效液相色谱-三重四极杆串联质谱（UPLC-MS/MS）建立槟榔籽中槟榔碱、槟榔次碱、去甲槟榔碱和去甲槟榔次碱含量的检测方法。方法:样品经45%乙醇水溶液提取,利用UPLC-MS/MS法进行检测。色谱条件:采用Waters Atlantis T3（2.1 mm×150 mm,5 μm）色谱柱分离,以0.1%甲酸水溶液-乙腈溶液为流动相进行梯度洗脱,流速0.5 mL·min?1,柱温40 ℃,进样量1 μL。质谱条件:采用电喷雾离子源（ESI+）,检测方式多反应监测（MRM）模式扫描;外标法定量。结果:在50~500 ng/mL,槟榔碱、槟榔次碱、去甲槟榔碱和去甲槟榔次碱的质量浓度与峰面积都呈现良好的线性关系（R2>0.99）;加样回收率均在规定范围70%~120%内,平均回收率在75.27%~96.70%,RSD<7.0%。结论:该方法的重复性、稳定性良好,仪器精密度较好。     

HPLC测定荷叶中碱盐的含量

以荷叶为原料,建立一种荷叶碱盐含量的测定方法.运用高效液相色谱法测定,色谱柱为Hypersil ODS2(4.6 mm×250 mm,5μm),流动相为乙腈-磷酸盐缓冲溶液(0.05%磷酸-0.2%三乙胺-水)(25:75,V/V),流速为1.0 mL/min,检测波长为270 nm.结果显示,荷叶碱盐在0.053～0.159 mg/mL(R2=0.999 2)范围内具有良好的线性关系,平均回收率为96.4%,RSD为0.05%.该方法简便、准确,灵敏度高,重复性好,可用于荷叶碱盐成分的含量测定.     

高效液相色谱-二极管阵列检测法同时测定不同品种巴旦杏中槲皮素、山奈酚的含量

目的:建立用高效液相色谱-二极管阵列检测法测定新疆不同品种巴旦杏仁中槲皮素、山奈酚含量的方法。方法:色谱柱:HC-C18柱(250 mm×4.6 mm,5μm);流动相:甲醇-0.4%磷酸溶液(55∶45,V/V);检测波长:360 nm;柱温:30℃;流速:1.00 mL/min。结果:槲皮素和山奈酚分别在1.0~30μg/mL(r=0.999 3)和0.5~40μg/mL(r=0.999 8)质量浓度范围内呈良好的线性关系,平均回收率分别为102.0%(相对标准偏差为2.08%,n=5)和102.8%(相对标准偏差为2.21%,n=5)。结论:该方法简便、快速、有效、准确、具有良好的重复性和回收率,可作为巴旦杏仁的质量控制和评价。     

高效液相色谱法测定黄瓜和番茄中苯丁锡残留量

目的建立黄瓜、西红柿中苯丁锡残留量的检测方法。方法样品采用二氯甲烷:乙腈(V:V=1:2)溶液振摇提取,用N-丙基乙二胺(PSA)作为净化剂净化,采用PhenomenexKinetex EVO C_(18)柱(4.6 mm×150 mm,5μm),以乙腈:0.01 mol/L盐酸(含0.6%氯化钠)(V:V=85:15)为流动相等度洗脱分离,流速1.0 mL/min,在220 nm波长处用高效液相色谱法检测。结果苯丁锡在0.5~50mg/L范围内线性关系良好。平均回收率为92.9%~98.6%,相对标准偏差(RSD)在0.7%~5.0%之间(n=6),检出限为0.05 mg/kg。结论该方法操作简便、准确、可靠,可用于黄瓜、西红柿等蔬菜中苯丁锡残留量的测定。     

离子色谱法快速测定猪肉中的三甲胺

试验建立了离子色谱法测定猪肉中的三甲胺的方法。选用Ion Pac CG 17型阳离子交换色谱柱(50 mm×4mm),以25 mmol/L甲基磺酸溶液为流动相,流速为0.8 mL/min,电导检测。结果表明:三甲胺在0.6～20μg/mL范围内与其色谱峰面积呈良好的线性关系,相关系数为0.999 9,检出限为0.3 mg/kg,定量限为3 mg/kg,精密度良好,溶液放置6 h内稳定。在15, 30和60 mg/kg的添加水平下方法平均回收率为98.52%,相对标准偏差为2.36%(n=9)。该方法前处理简单快速,灵敏度高,回收率和重现性良好,适用于猪肉中三甲胺的快速测定。     

湘莲莲房中主要生物碱成分提取方法优化与含量测定

目的以莲心碱、异莲心碱、甲基莲心碱为湘莲莲房质量评价指标,优化提取工艺参数,建立高效液相色谱法同时测定3种物质。方法用酸性80%乙醇作溶剂超声提取莲房生物碱类成分,碱化后分离定量。经Waters XSelect C₁₈色谱柱(250 mm×4.6 mm,5μm)进行分离,以甲醇-0.05 mol/L磷酸二氢钠为流动相进行梯度洗脱。结果莲心碱、异莲心碱、甲基莲心碱分别在1.994~79.76μg/mL(r²=0.9993,n=6)、1.951~78.05μg/mL(r²=0.9996,n=6)、1.972~78.87μg/mL(r²=0.9998,n=6)范围内线性关系良好,回收率分别为99.5%、98.2%、98.7%(n=9)。结论该方法简便、回收率高,实验结果为莲房中生物碱定量分析和湘莲莲房质量评价提供参考。     

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