大孔吸附树脂纯化乌饭树果色素的研究

研究了以乌饭树果提取液为原料,用大孔吸附树脂分离纯化乌饭树果色素的工艺,分别用AB-8、X-5、NKA-9、D101、D3520对其进行静态吸附解吸实验,筛选出分离效果较好的D101树脂。通过对D101树脂分离乌饭树果色素的进一步的静动态实验,结果表明,D101树脂在20℃、pH4.0时吸附能力较强,被吸附的乌饭树果色素用80%乙醇洗脱,洗脱时间为100min,洗脱流速为0.5BV/h时洗脱效果较好。     

响应面试验优化新疆野生准噶尔山楂残渣中多糖纯化工艺

为纯化准噶尔山楂残渣中的粗多糖,通过动态吸附和洗脱实验从7 种大孔吸附树脂中选出两种最优树脂NKA-9和D101,按一定比例进行混合实验。在单因素试验基础上,利用响应面法确定最佳纯化条件：NKA-9与D101树脂最佳混合质量比为2∶3;最佳吸附工艺条件为上样液流速3.75 mL/min、上样液质量浓度1.32 g/L、树脂径高比1∶13,此条件下多糖的吸附率为60.75%;最佳洗脱工艺条件为洗脱液浓度0.27 mol/L、洗脱液流速3.5 mL/min、洗脱液用量7 BV,此条件下多糖的洗脱率为84.22%。样品中多糖含量由原来的5.06%上升至21.13%。     

D101大孔树脂对桃花红色素吸附行为的研究

研究了大孔吸附树脂对桃花红色素(RPPB)的吸附分离特性.通过比较吸附量和解吸率,在3种所选树脂中,D101树脂具有较好的吸附和解吸效果.随后对D101树脂动态吸附性能进行了考察,实验表明,D101树脂对RPPB的最佳吸附条件是:上样浓度为7.0～9.6mg/mL,上样流速为0.5～2.0mL/min;以80%乙醇为洗脱剂、流速为0.25mL/min时,洗脱效果最好.D101树脂适宜于工业精制RPPB.     

D101树脂分离纯化芡实多酚的特性研究

采用50%丙酮溶液对芡实中的多酚进行分离提取。在D101树脂对芡实多酚吸附特性研究的基础上,采用D101树脂吸附-柱层析分离法,对芡实多酚进行纯化。结果显示,D101树脂对溶液体系中芡实多酚的平衡吸附量为33.21mg/g,在蛋白质、低聚糖和多酚等组分共存的溶液体系中,D101树脂对芡实多酚的吸附具有较高的选择性。芡实多酚经D101树脂吸附后,用pH5、50%丙酮溶液(V/V) 洗脱,即可将其中91.84%的芡实多酚洗脱下来。洗脱液经减压浓缩、干燥后,得到纯化芡实多酚样品,其中总酚含量达81.38%。     

D101大孔树脂纯化番茄皂苷的工艺研究

为了研究D101大孔树脂分离纯化番茄总苷的工艺条件及技术参数,采用高效液相色谱法测定番茄皂苷A的含量,考察D101大孔树脂对番茄总苷的吸附及解吸性能。结果表明,D101大孔树脂对番茄总苷的适宜吸附条件为:最大番茄鲜果树脂比为10:1(g/mL),pH值3.75～5.0,流速2BV/h(BV为柱床体积倍数),洗脱剂用4BV80%乙醇,洗脱流速为2.0BV/h。D101大孔树脂吸附番茄总苷的纯化方法可行,具有较好的应用前景。为实现番茄皂苷的工业化生产提供理论依据和参考。     

大孔吸附树脂纯化黑果枸杞中的原花青素

采用大孔吸附树脂对黑果枸杞中的原花青素粗提液进行纯化。以吸附能力和解吸附能力为指标,考察了AB-8,D130,D101,HPD100,D101-1和聚酰胺6种树脂对原花青素的纯化效果;以解吸能力为指标,考察洗脱剂体积分数、洗脱流速对洗脱效果的影响。结果表明,以D101树脂可用于黑果枸杞中原花青素的纯化,静态吸附以后,使用95%的乙醇,在2.5 BV/h的洗脱速度下,用4.0 BV进行洗脱,原花青素纯度由31.33%提高至68.03%;通过乙酸乙酯萃取可制得低聚原花青素样品,其平均聚合度由8.98降低至3.17,用HPLC方法可检测到低聚物中含有儿茶素、表儿茶素、原花青素B2等重要的原花青素单体和低聚物,根据峰面积计算三种物质的总含量达18.73%。     

菠萝皮中总多酚的纯化工艺研究

考察大孔吸附树脂对菠萝皮中多酚的纯化效果。比较5种树脂的吸附和解吸能力,从中筛选出适合分离菠萝皮总多酚的树脂,并对其吸附和解吸条件进行优化。结果表明,D101为纯化菠萝皮总多酚的最佳树脂,最佳纯化条件:上样流速为1.5mL/min,上柱样液为3.9mg/mL,解吸剂为80%乙醇,洗脱流速为1.0mL/min洗脱时,经D101精制的菠萝皮总多酚的纯度为39.03%。     

AB-8和D-101大孔吸附树脂分离纯化玉竹多糖

以葡萄糖为标准品,利用大孔吸附树脂分离纯化玉竹多糖,结果表明AB-8大孔吸附树脂分离纯化玉竹多糖的最佳上样浓度为1.0 mg/m L,最佳洗脱浓度为75%乙醇,最佳流速为1.0 m L/min,洗脱液体积为上样的10 BV,玉竹粗多糖的纯度从65.23%提高到78.64%;D-101大孔吸附树脂分离纯化玉竹多糖的最佳上样浓度为0.6 mg/m L,最佳洗脱浓度为50%乙醇,最佳流速为1.0 m L/min,洗脱液体积为上样的10.5 BV,玉竹粗多糖的纯度从65.23%提高到73.79%。AB-8大孔吸附树脂对玉竹多糖的分离纯化效果优于D-101大孔吸附树脂。     

大孔树脂分离纯化甜菜红色素的研究

比较了AB-8、D3520、D101、X-5、HPD-100A、D101-1大孔树脂对甜菜红色素的吸附纯化效果,结果表明,D3520大孔树脂对甜菜红色素具有较好的吸附解析能力。动态吸附和解析研究表明,D3520大孔树脂最佳吸附条件:上样浓度2mg/m L,上样速度3m L/min,上样p H为3;洗脱最佳条件:70%乙醇,2m L/min的洗脱速度,4BV的洗脱体积。纯化后甜菜红色素纯度增加6倍多,色阶由处理前的17.62变为108.53,进一步提高了色素的纯度和透明度。     

聚酰胺-大孔树脂联用富集桑叶总黄酮工艺研究

样品溶液先以聚酰胺吸附,水洗除杂,再将除杂后的聚酰胺加于大孔吸附树脂顶部,以乙醇洗脱,富集桑叶总黄酮。试验结果显示聚酰胺与D-101大孔树脂联用能有效富集桑叶中的总黄酮。最佳工艺条件为聚酰胺料液比2.50 g/m L,大孔树脂料液比5.50 g/m L,以80%乙醇洗脱,收集洗脱液6 BV,富集总黄酮纯度为48.09%。该方法优于目前常用的桑叶总黄酮富集方法,工艺稳定简单,具有较好的可行性。     

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