杏鲍菇碱溶性多糖的酶法提取及其结构的初步分析

以杏鲍菇子实体为原料提取并分离纯化,得到碱溶性多糖组分,通过采用正交实验得到了提取碱溶性多糖的最佳方案。该多糖经层析方法和Smith降解等反应,证实其为单一组分,该组分多糖由葡萄糖为单一糖基组成;并证实了该多糖具有β(1→3)及β(l→6)连接的糖苷键。      

燕麦中β-葡聚糖的分离纯化及结构表征

以我国山西产燕麦(晋燕8号)为原料提取并分离纯化,得到Oglu-1和Oglu-2两个燕麦β-葡聚糖级分,经凝胶渗透色谱层析和Sephacryl-400SF柱层析,证实Oglu-1为单一组分,纸层析和HPLC分析表明该级分多糖由葡萄糖为单一糖基组成,红外光谱和核磁共振分析证明该多糖分子链中存在β-(1→4)和β-(1→3)两种糖苷键,其比例为2.1:1,该结果与国外学者的研究基本一致。采用凝胶渗透色谱和激光光散射联用仪(GPC-LLS)测定Oglu-1的重均相对分子质量为4.49×105。     

伸筋草多糖镇痛功效成分的分离鉴定

采用乙醇提取、水提取乙醇沉淀得到伸筋草不同提取物,利用醋酸扭体和热板模型,以小鼠扭体反应时间和舔后足时间为指标,筛选镇痛组分,并通过核磁共振鉴定化学结构。结果表明：伸筋草水提取物具有镇痛作用,经进一步分析筛选得出伸筋草镇痛功效成分为多糖,从粗多糖中得到一个单一组分多糖,通过核磁对其进行结构分析,推测该多糖主链是由(1→4)-β-葡萄糖组成,2位上连有侧链,6位上连有乙酰基。     

伸筋草多糖镇痛功效成分的分离鉴定

采用乙醇提取、水提取乙醇沉淀得到伸筋草不同提取物,利用醋酸扭体和热板模型,以小鼠扭体反应时间和舔后足时间为指标,筛选镇痛组分,并通过核磁共振鉴定化学结构。结果表明:伸筋草水提取物具有镇痛作用,经进一步分析筛选得出伸筋草镇痛功效成分为多糖,从粗多糖中得到一个单一组分多糖,通过核磁对其进行结构分析,推测该多糖主链是由(1→4)-β-葡萄糖组成,2位上连有侧链,6位上连有乙酰基。     

茯苓多糖与产地及炮制方法的关联性研究

共收集了云南、广西、贵州、湖南、安徽等5省区不同菌种和炮制方法的茯苓样品15份,脱脂后分别用0.9%NaCl水溶液、120℃热水、0.5mol/LNaOH水溶液和88%甲酸溶液从茯苓中提取出了6种多糖,并测定此6种多糖的含量以确定茯苓多糖含量与产地及炮制方法的关联性。对PCS4-A多糖组分进一步使用1HNMR测定了-(1→3)/β-(1→6)糖苷键的摩尔比。结果表明:茯苓中碱溶性多糖PCS3-B组分是茯苓多糖的主要组分,占总多糖的90%以上。比较茯苓多糖的含量,实际上是比较PCS3-B组分的含量差异。在所选择的产地范围内,以云南省的样品PCS3-B组分含量最高,其总多糖含量亦高。不同的炮制方法对茯苓多糖组分含量有较大影响,同一产地、同菌种、同一栽培条件下,烤制的茯苓,其主要组分PCS3-B的含量高于晒制的茯苓;但同一产地,同一炮制方法时,茯苓多糖的主要组分含量亦相差较大,表明产地并非影响茯苓多糖含量的决定因素,茯苓多糖含量可能还与菌种、培养基材等性质有关。茯苓多糖的PCS4-A组分的-(1→3)/β-(1→6)糖苷键的摩尔比与产地有很密切的关系,但与炮制方法无关,云南产地样品的分支化度最低。     

碱溶性米糠多糖的提取及其免疫调节功能研究

本文研究了不同提取温度、提取时间和碱摩尔浓度对碱溶性米糠多糖提取得率的影响。采用响应面分析的方法得到碱溶性米糠多糖的最佳提取条件为：温度44．5℃，时间2．13h，NaOH浓度0．53mol/L。并在此基础上，采用动物试验证明碱溶性米糠多糖具有免疫活性增强作用。     

黑小麦麦麸多糖的制备与分析

分别以水和饱和Ba(OH)2溶液为提取介质,采用高压辅助水提取、Ba(OH)2碱提取和碱后水提取等方法制备黑小麦麦麸中的水溶性和水不溶性多糖,并采用气相色谱(GC)、高效液相色谱(HPLC)和红外光谱(IR)分析黑小麦麦麸多糖组分的理化性质。结果表明:高压辅助水提组分(WEPH)主要由葡萄糖(G lc)、阿拉伯糖(Ara)和木糖(Xyl)组成,是β-葡聚糖和戊聚糖的混合物;Ba(OH)2碱提组分(AEPH)主要由Ara和Xyl组成,物质的量比为Ara:Xyl=1:1.66,表明含有较纯的戊聚糖,其Ara/Xyl比值为0.60;碱后水提组分(AEPH-H2O)的85%由葡萄糖(G lc)和半乳糖(Man)组成,主要为β-葡聚糖和阿拉伯半乳聚糖,以及少量戊聚糖。富含戊聚糖的AEPH组分相对分子质量最高,为3.81×105,而以β-葡聚糖为主的WEPH和AEPH-H2O组分的相对分子质量较低,其中单一峰组分AEPH-H2O为2.40×105。     

窑归多糖提取工艺研究

本实验以窑归为主要原料,研究水溶性和碱液性窑归多糖的提取工艺。窑归经破碎、提取、酒精沉淀多糖、Sevag法脱蛋白、水透析、醇析等方法得出较高纯度的多糖,最后,通过真空冷冻干燥分别得到水溶性多糖和碱溶性多糖,经红外光谱证实:水溶性多糖和碱溶性多糖具有一般多糖的特征。水溶性多糖的最佳提取参数是:3h、1:25、加水,其提取率是3.32%;碱溶性多糖的最佳提取参数是:1mol/L的NaOH溶液提取6h、加1:25的碱液,其提取率是4.31%。     

碱溶性银耳粗多糖的提取及其清除自由基作用的研究

本实验研究了碱溶性银耳粗多糖(crude alkai-soluble tremella polysaccharide,CATP)的提取及其清除自由基的作用。利用响应面软件进行实验设计,确定最佳提取方案为:提取时间3.56h,NaOH浓度0.76mol/L,液固比81.89。同时考察了碱溶性银耳粗多糖和水溶性银耳粗多糖(tremella polysaccharide,TP)对DPPH(二苯代苦肼基自由基)、羟基自由基、超氧自由基的清除作用。结果表明,碱溶性银耳粗多糖具有良好的抗氧化能力,并且随着多糖浓度的增高抗氧化性增强。     

葛仙米多糖的提取、分离与纯化技术研究

葛仙米中富含多糖，并且具有优异的生物和生理活性，本文对葛仙米多糖的提取、分离进行了初步的研究，以期获得性能优良的葛仙米多糖。葛仙米经破碎、脱色、去脂、提取、Sevage法沉淀蛋白质、酒精沉淀多糖、离心、得到粗多糖，最后，通过真空冷冻干燥得到白色的水溶性多糖和褐色的碱溶性多糖，经红外光谱证实：水溶性多糖和碱溶性多糖具有一般多糖的特征。水溶性多糖的最佳提取参数是：90℃，6h，1：90加水，水提取4次，其提取率是14．09％；碱溶性多糖的最佳提取参数是：1mol／L的NaOH溶液，提取6h，加1：25的碱液，提取4次，其提取率是5，70％。     

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