人工培养冬虫夏草胞外多糖的分离纯化及组成分析

将冬虫夏草菌丝体培养液以醇沉法提取多糖,通过DEAE-52纤维素层析柱和Sephadex G-100凝胶层析柱分级纯化后得到两种单一的中性多糖组分EPS-1w和EPS-2w。应用紫外分光光度、Sephadex G-100凝胶柱层析法和比旋度法鉴定多糖的纯度,凝胶过滤法、理化实验和高效液相色谱研究其相对分子质量、理化性质及组成。结果表明:EPS-1w和EPS-2w为均一组分且易溶于水、稀酸、碱,其平均分子量分别约为4.65×104u和3.48×104u,均主要是由D-甘露糖、D-葡萄糖、D-半乳糖组成,其物质的量比分别为23.7∶6.2∶8.5和35∶3.6∶3.1。     

玉竹水溶性多糖POPS-B1单糖组成研究

采用半透膜和Sephadex G-75凝胶柱层析对玉竹粗多糖(POPS)进行分离纯化,分离出玉竹水溶性多糖POPS-B1,利用旋光度法和凝胶柱法检测其纯度,并用TLC和GC两种方法鉴定出其单糖组成为D-甘露糖和D-葡萄糖。     

铁皮石斛多糖分离纯化及单糖组成测定

将铁皮石斛粗多糖经DEAE-52纤维素柱分离得到了四个多糖组分(DO-1、DO-2、DO-3、DO-4),并将组分DO-1经Sephadex G-200柱纯化得到多糖DOP。采用1-苯基-3-甲基-5-吡唑啉酮(PMP)柱前衍生化方法进行高效液相色谱分析,分析结果得出,多糖DOP由D-甘露糖、L(+)-鼠李糖和D-葡萄糖三种单糖组成,通过外标法定量得知D-甘露糖∶L(+)-鼠李糖∶D-葡萄糖=1.936∶0.856∶0.691。测定了多糖DOP抗氧化活性,结果显示其具有良好的清除能力。     

南海鸢乌贼墨汁多糖分离纯化及组分分析

目的:从南海鸢乌贼墨汁中分离纯化多糖,并分析其多糖组分。方法:利用水提醇沉法得粗多糖,通过固相萃取层析法除色素对多糖进行纯化,纯化多糖依次经DEAE-52离子交换柱、Sephacryl HR-300凝胶柱分级纯化,按峰收集得单一组分,采用1-苯基-3-甲基-5-吡唑啉酮(1-phenyl-3-methyl-5-pyrazolone,PMP)衍生化方法,通过超高效液相色谱分析多糖组分。结果:粗多糖经DEAE-52离子交换柱、Sephacryl HR-300凝胶柱后收集得到3个糖组分,分别为SIP1、SIP2、SIP3;通过PMP衍生化方法分析单糖组成,得:SIP1是由D-甘露糖、D-葡萄糖、D-半乳糖3种单糖缩合而成;SIP2和SIP3分别是由D-甘露糖、鼠李糖、D-葡萄糖、D-半乳糖及L-(-)-岩藻糖5种单糖按照不同比例缩合而成。     

一种具有自由基清除活性的酸性苦瓜多糖的分离纯化及单糖组成分析

苦瓜粗多糖(MCP)经DEAE-纤维素凝胶柱层析及Sephadex G-100凝胶柱层析纯化后,得到多糖组分MCP Ia,经紫外光谱分析及醋酸纤维素薄膜电泳法纯度检验,结果表明MCP Ia是单一组分。HPLC分析其单糖组成为L-鼠李糖、D-木糖、D-果糖和D-半乳糖,单糖物质的量比为4.4:2.3:1:5.7,另外,MCP Ia还可能含有葡萄糖;MCP Ia红外光谱表明:苦瓜多糖存在分子内和分子间的氢键,分子中存在C—H键伸缩振动,存在—OH的变形振动,存在呋喃糖苷吸收峰,是典型的多糖类化合物。     

新疆昆仑雪菊多糖的分离纯化及其结构的初步鉴定

以新疆昆仑雪菊为原料,采用超声波辅助法提取雪菊多糖（KSCP）,经脱蛋白、脱色、透析、DEAE-52层析柱和SephadexG-100凝胶层析柱纯化后,获得两个多糖组分（KSCP1和KSCP2）;将分离纯化后的多糖组分经紫外光谱分析法、冻融分析法、SephadexG-100凝胶柱层析法对其纯度进行鉴定;采用凝胶渗透色谱法和气质联用法（GC-MS）对KSCP分子质量范围和单糖组成进行分析。结果表明,KSCP1和KSCP2均为单一组分;KSCP1是由葡萄糖、阿拉伯糖、半乳糖、木糖4种单糖组成,其摩尔比为10.53∶5.02∶4.96∶1,分子质量范围为8 200～8 700 u;KSCP2主要由葡萄糖、阿拉伯糖、半乳糖3种单糖组成,其摩尔比为1∶2.78∶5.07,分子质量范围为6 100～6 500 u。     

中国被毛孢发酵虫草菌丝体多糖的提取、纯化及其理化性质

利用中国被毛孢虫草菌液体深层发酵培养得到的菌丝体,通过正交试验优化得到了虫草多糖的提取工艺条件为:提取温度100℃,提取时间120 min,料液比1∶15,提取次数4次。粗多糖经Sevag法脱蛋白、透析袋透析、DEAE-cellulose离子交换和Sephadex G-100柱层析纯化后,得到3种多糖(命名为HSP-1、HSP-2和HSP-3)。经紫外扫描、Sephacryl S-300 HR柱层析检测确定HSP-1和HSP-2为均一组分,HSP-3为非均一组分。苯酚-硫酸法测得HSP-1和HSP-2的含糖量分别为89.42%和85.63%。Sephacryl S-300 HR柱层析测得HSP-1和HSP-2的相对分子质量分别为1.7×104Da和9.8×103Da。GC-MS测得HSP-1的单糖组成及比例为:D-葡萄糖∶D-甘露糖∶D-半乳糖=4.522∶1∶1.378,HSP-2的单糖组成及比例为:D-葡萄糖∶D-甘露糖∶D-半乳糖∶D-阿拉伯糖=2.687∶4.591∶1∶0.212。红外光谱测定结果显示HSP-1和HSP-2都含有α型糖苷键。     

南极海茸多糖结构及其单糖组分的分析

文中对南极海茸多糖的理化性质、结构及其单糖组成进行了分析研究。南极海茸干品经脱脂、微波提取、Sevag法脱蛋白和分级醇沉得到海茸粗多糖,经过阴离子交换柱层析和凝胶层析分离得到均一多糖HRCS,采用HPLC、紫外全扫描、红外光谱扫描和气相色谱(GC)对海茸多糖结构进行光谱分析和单糖组成分析。结果表明:HRCS的分子质量为1.79×105Da,不含蛋白质和核酸,其中的单糖残基主要以α-构型和β-构型的吡喃环的形式存在,另外HRCS由L-岩藻糖、D-半乳糖和D-葡萄糖组成,摩尔比为2.18∶0.82∶1。     

螺旋藻多糖提取新工艺的研究

采用双酶法提取螺旋藻多糖,脱蛋白效果接近100% .通过DEAE-Sepharose和Sephadex-G50纯化粗多糖,得到2个多糖组分.经测定组分1的单糖组成为D-葡葡糖、D-木糖、D-半乳糖、葡萄糖醛酸;组分2的单糖组成为:D-葡萄糖、D-甘露糖、L -鼠李糖、D-半乳糖、葡萄糖醛酸.     

南瓜多糖的提取及纯化

南瓜是一种具有药用价值的食品,实验用热水浸提、醇析、Severge法除蛋白,水相透析得到南瓜粗多糖,通过DEAE-Sepharose和SephadexG-100柱的分离纯化得到2种水溶性多糖,经酸解,纸色谱分析得组分1的单糖组成为D-葡萄糖、L-阿拉伯糖、D-半乳糖和葡萄糖醛酸,组分2的单糖组成为D-葡萄糖、D-半乳糖、D-木糖和葡萄糖醛酸。     

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