大孔吸附树脂法分离纯化白藜芦醇的研究

利用大孔吸附树脂分离纯化虎杖中的白藜芦醇。实验结果表明，NKA-9型大孔吸附树脂对白藜芦醇的吸附、解吸性能较好。在料液浓度3-4mg／ml，上柱速率1ml／min，上样量0．5BV，pH值为4的条件下吸附；解吸采用75％酒精，解吸流速1ml／min，pH值为8时可以将白藜芦醇较好的纯化。     

花生红衣中自藜芦醇、原花色素提取工艺的研究

对超声波辅助提取花生红衣中白藜芦醇、原花色素的工艺进行了研究。从5种常用试剂中选择出乙醇作为提取剂，并在单因素实验的基础上，通过正交实验优化了白藜芦醇、原花色素的提取条件：料液比1：6，温度70℃，乙醇浓度60％，提取时间20min，pH3，提取次数1次；在最佳工艺条件下，白藜芦醇、原花色素的提取得率分别为0．036％、4．96％。     

花生红衣中白藜芦醇、原花色素提取工艺的研究

对超声波辅助提取花生红衣中白藜芦醇、原花色素的工艺进行了研究。从5种常用试剂中选择出乙醇作为提取剂,并在单因素实验的基础上,通过正交实验优化了白藜芦醇、原花色素的提取条件:料液比1:6,温度70℃,乙醇浓度60%,提取时间20min,pH3,提取次数1次;在最佳工艺条件下,白藜芦醇、原花色素的提取得率分别为0.036%、4.96%。     

大孔树脂对曲霉型豆豉类黑精的精制研究

研究了大孔树脂吸附和解吸曲霉型豆豉类黑精的特性。实验结果表明,采用大孔树脂精制曲霉型豆豉类黑精的最佳条件为:X-5树脂对曲霉型豆豉类黑精的吸附效果最好;X-5树脂在类黑精溶液pH为6,浓度为30．12mg/ml,吸附流速为1．5ml/min时吸附能力较强;在室温(20℃)解吸流速为1．5ml/min的条件下,以60%乙醇作为解吸剂时洗脱效果最好。     

大孔吸附树脂分离纯化葡萄多酚的研究

通过吸附、解吸试验，筛选适合分离纯化葡萄多酚的大孔吸附树脂并确立纯化工艺参数。结果表明，AB-8型大孔吸附树脂对葡萄多酚分离效果良好，较佳动态吸附条件为上溶液多酚浓度3．0g／L，pH4．5，上样速率为3BV／h，较佳洗脱条件为乙醇浓度80％，洗脱速率3BV／h，在此条件下，葡萄多酚纯化样品多酚含量为81．1％     

香草醛/硫酸比色法测定两种原花色素含量的比较

分别选取儿茶素、葡萄籽原花青素、沙棘籽原花色素为基准物质,考察了三者与香草醛/硫酸反应影响因素的异同,优化了各自的测定条件,结果表明,儿茶素、葡萄籽原花青素和沙棘籽原花色素与香草醛反应动力学有显著差异。儿茶素的适宜反应条件为:30℃反应5min(测定波长500nm),葡萄籽原花青素的适宜反应条件为:20℃反应5min(测定波长500nm);沙棘籽原花色素适宜反应条件为:30℃反应15min(测定波长505nm);反应体系为:1ml样品甲醇溶液加入2.5ml 1%香草醛的甲醇溶液和2.5ml 5mol/L硫酸的甲醇溶液。     

大孔树脂分离纯化枳实总黄酮工艺研究

目的研究大孔吸附树脂富集、纯化枳实总黄酮的工艺条件及参数。方法以总黄酮含量、吸附率及解吸率为指标筛选分离纯化枳实总黄酮的工艺。结果柱流速1mL／min,上柱液浓度约1．0mg／mL,除杂洗脱水用量75mL,洗脱剂乙醇浓度50％,乙醇用量52．5mL时,枳实总黄酮含量达92．78％。结论D101型大孔树脂对枳实总黄酮有较好的吸附分离性能,是分离纯化枳实总黄酮的适宜大孔树脂。     

大孔树脂分离纯化枳实总黄酮工艺研究

目的研究大孔吸附树脂富集、纯化枳实总黄酮的工艺条件及参数。方法以总黄酮含量、吸附率及解吸率为指标筛选分离纯化枳实总黄酮的工艺。结果柱流速1mL／min,上柱液浓度约1．0mg／mL,除杂洗脱水用量75mL,洗脱剂乙醇浓度50％,乙醇用量52．5mL时,枳实总黄酮含量达92．78％。结论D101型大孔树脂对枳实总黄酮有较好的吸附分离性能,是分离纯化枳实总黄酮的适宜大孔树脂。     

吸附树脂法分离纯化酿酒用葡萄中白藜芦醇的研究

以酿酒用葡萄为原料,研究提取、分离白藜芦醇的方法与条件,建立了最佳提取工艺与纯化工艺.以酒葡萄皮为原料,采用超声波辅助法和有机溶剂的提取,得到白藜芦醇的粗提液.正交试验表明,采用60%甲醇溶液作为溶剂,最佳提取条件为浸提温度60℃,浸提时间40 min,料液比为1:40,浸提2次.以NKA-Ⅱ、NKA-9和D101 3种大孔吸附树脂做为吸附剂,柱层析法纯化白藜芦醇,结果表明,NKA-9大孔吸附树脂填充的色谱柱为最佳吸附树脂,动态饱和吸附量约为2-31 mg/mL湿树脂;解吸采用75%甲醇,解吸流速1 mL/min,pH值8,可较好纯化白藜芦醇.     

生物吸附剂去除水中六价铬的实验研究

从活性污泥等中筛选、分离得到的菌株B—5和C—7作为生物吸附剂，研究了它们对水中六价铬的吸附。实验结果表明：B—5和C—7对六价铬吸附的最佳pH分别为6．5和5．0，温度为30℃，用量为1ml／L；B—5在[Cr^5 ]=40g／L的吸附率达到最大值，为80．5％，C—7在[Cr^5 ]=35g／L达到78．6％；当HCl浓度大于0．5M时，两种菌株的解析率可达90％以上，基本上可以完全解析。     

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