河蚬糖蛋白体外免疫功能研究

目的:研究河蚬糖蛋白对小鼠体外免疫功能的影响。方法:无菌分离小鼠脾淋巴细胞和腹腔巨噬细胞,与不同质量浓度(5、25、125、625μg/mL)的河蚬粗糖蛋白和高纯度糖蛋白CFP共同培养,采用MTT法测定其对淋巴细胞增殖和腹腔巨噬吞噬能力的影响。结果:在无有丝分裂原诱导下,125μg/mL的粗糖蛋白和4个浓度的CFP都有促进脾淋巴细胞的作用。在有丝分裂原刺激下,粗糖蛋白和CFP的刺激指数都比未加有丝分裂原时增大。125μg/mL粗糖蛋白和4个浓度的CFP都有提高巨噬细胞的吞噬能力,且2种河蚬糖蛋白都表现出一定的剂量效应关系。结论:河蚬粗糖蛋白和CFP均有免疫增强活性,其中CFP的活性较强。     

蒲公英糖蛋白的分离纯化及结构分析

通过DEAE-52纤维素柱层析和Sephadex G-100葡聚糖凝胶层析手段分离纯化,从蒲公英中分离纯化得到三种蒲公英糖蛋白（TMGP）-a、b、c,采用薄层层析法对其纯度进行鉴定,结果显示三种成分均为均一组分。经分析,蒲公英糖蛋白粗品TMGP和均一品TMGP-a、TMGP-b、TMGP-c中多糖的含量为79.12%、71.23%、70.25%、74.35%;蛋白质的含量为:13.35%、19.79%、20.78%、17.60%。β-消除反应说明三种蒲公英糖蛋白均一品都含有O-连接型糖蛋白。经红外光谱分析,TMGP-a糖蛋白可能含有少量硫酸基;TMGP-b糖链中可能是硫酸化多糖;TMGP-c含有吡喃糖β-糖苷键。      

蒲公英糖蛋白的分离纯化及结构分析

通过DEAE-52纤维素柱层析和Sephadex G-100葡聚糖凝胶层析手段分离纯化,从蒲公英中分离纯化得到三种蒲公英糖蛋白(TMGP)-a、b、c,采用薄层层析法对其纯度进行鉴定,结果显示三种成分均为均一组分。经分析,蒲公英糖蛋白粗品TMGP和均一品TMGP-a、TMGP-b、TMGP-c中多糖的含量为79.12%、71.23%、70.25%、74.35%;蛋白质的含量为:13.35%、19.79%、20.78%、17.60%。β-消除反应说明三种蒲公英糖蛋白均一品都含有O-连接型糖蛋白。经红外光谱分析,TMGP-a糖蛋白可能含有少量硫酸基;TMGP-b糖链中可能是硫酸化多糖;TMGP-c含有吡喃糖β-糖苷键。     

菲律宾蛤仔糖蛋白的分离纯化与理化性质的研究

对菲律宾蛤仔全脏器中的糖蛋白进行分离纯化,并分析其理化性质.菲律宾蛤仔全脏器经热水煮提、DEAE-52 纤维素柱层析及Sephadex G-100柱层析分离纯化,所得纯化组分用SDS-PAGE鉴定纯度并测定其相对分子质量;用HPLC检测糖链的单糖组成,再用IR分析其基团结构.结果表明:菲律宾蛤仔经柱层析纯化得到1种中性糖蛋白(NGP)和3种酸性糖蛋白(AGP,主要组分为AGP-Ⅲ).NGP的相对分子质量为35000, 总糖及总蛋白质量分数分别为60.5%和18.2%,糖链部分主要是由木糖、葡萄糖、半乳糖组成.AGP-Ⅲ的相对分子质量为43 000,总糖与蛋白的质量分数分别为57.4%和22.0%,糖链部分主要含有木糖、葡萄糖、半乳糖、阿拉伯糖等.IR分析表明,NGP和AGP-Ⅲ均含有多糖的-OH、-COO-、-NH、-C-O-C等特征基团.     

酶转化人参皂苷中25-OH-Rg2的纯化及结构鉴定

以分离纯化及结构鉴定人参皂苷Re酶转化产物中未知皂苷为目标,采用酶转化法制备产物,经硅胶柱层析、结晶和重结晶对未知皂苷进行分离纯化,并进行核磁共振结构鉴定。酶转化法制备的产物中,主要含有20（S,R）-Rg2、少量的Rg4和Rg6,以及HPLC检测为双峰的手性异构体未知皂苷,酶转化得率为65.5%（w/w）。采用硅胶柱层析和结晶重结晶方法,纯化得到了0.33 g纯度达99.7%的一种未知皂苷,经核磁共振技术检测确定该未知皂苷为20（R）-25-OH-Rg2,系统名称为3β,12β,20（R）,25-tetrahydroxydammar-6-O-α-L-rhamnopyranosyl-（1→2）-β-Dglucopyranoside,以及另一种未知皂苷20（S）-25-OH-Rg2,系统名称为3β,12β,20（S）,25-tetrahydroxydammar-6-O-α-L-rhamnopyranosyl-（1→2）-β-D-glucopyranoside。      

鲍鱼脏器糖蛋白超声辅助提取工艺及分离纯化的研究

以冻藏鲍鱼脏器为试验原料,分析了鲍鱼脏器的基本成分组成,研究了鲍鱼脏器糖蛋白的分离纯化及纯化物基本组成。通过单因素试验、正交试验确定了最适提取条件为:5%NaCl溶液、料液质量比1∶9、超声功率为300 W、超声处理时间为40 min,在此条件下,糖蛋白提取率为69.7 mg/g(干重),比传统方法提高了28.5%。糖蛋白粗品经硫酸铵沉淀,DEAE-Cellulous 52柱层析,SephacrylS-300 HR柱层析后,经SDS-PAGE电泳鉴定得到分子质量为73.7 ku的组成均一的糖蛋白AGP-Ⅱ,AGP-Ⅱ含有总糖12.4%,总蛋白76.6%。     

色谱法监测β-D-吡喃葡萄糖苷的合成

用改进的Koenigs-knorr法立体选择性地合成了2,3,4,6-四乙酰基-香叶基-1-O-β-D-吡喃葡萄糖苷(GLY-A)和香叶基-β-D-吡喃葡萄糖苷(GLY-B)两种键合态香料前体.采用薄层色谱法(TLC)监控反应条件;硅胶柱层析色谱法(SGCC)分离并纯化产物;反向液相色谱法(RP-HPLC)测定样品纯度...     

薏米中β-谷甾醇的分离纯化及其抗氧化活性的研究

以薏米为原料,采用大孔树脂分离纯化薏米中β-谷甾醇的粗提液,并进行抗氧化性质的研究。通过比较AB-8、D-101、DA-201三种树脂的静态吸附-解析效果,将AB-8树脂作为分离纯化的最佳树脂,并对其柱层析的吸附解析条件进行优化,进行DPPH和·OH清除能力的测定。得到β-谷甾醇分离纯化的最佳工艺条件为:树脂质量3 g,进样浓度0.55 mg/mL,75%乙醇的洗脱速度1 mL/min,此条件下得到β-谷甾醇回收率的平均值为85.56%,与预测值86.2707%接近,β-谷甾醇的纯度由原来的13.8%提高到76.17%。结果表明:AB-8树脂的分离纯化效果较好。抗氧化活性表明β-谷甾醇具有很好的抗氧化活性。     

墨鱼缠卵腺糖蛋白提取工艺优化及纯化

本文以墨鱼缠卵腺为实验原料,通过单因素实验及响应面试验优化墨鱼缠卵腺糖蛋白的提取工艺,随后对最优工艺下得到的糖蛋白进行分离纯化,电泳分析其纯度,并进一步研究其蛋白及总糖含量。结果表明,墨鱼缠卵腺糖蛋白提取最佳工艺为提取温度24 ℃,提取时间3.6 h,NaOH浓度0.4 mol/L,料液比1:20 g/mL,超声功率200 W。在此条件下进行验证试验,得出墨鱼缠卵腺糖蛋白实际得率为16.13%±0.16%;经DEAE-52纤维素离子交换柱层析、Sephacryl S-300HR柱层析分离后得到纯品糖蛋白,电泳分析表明所纯化的糖蛋白纯度达到电泳纯,其中蛋白含量为65.53%±0.8%,糖含量为31.74%±1.1%,得率为墨鱼缠卵腺去外层薄膜原料的0.91%。     

鳕鱼多肽的抗氧化活性及其分离纯化

研究了鳕鱼多肽的抗氧化活性及分离纯化.为获得高纯度的抗氧化肽,将鳕鱼多肽依次通过超滤、凝胶过滤层析、阴离子交换层析(Q-FF)和反相高效液相色谱层析(RP-HPLC)进行分离纯化.结果表明:鳕鱼多肽具有很强的清除羟自由基的能力、清除DPPH的能力和还原能力;经Q-FF柱层析分离得到了B1、B2和B3 3个组分,B2经RP-HPLC检测显示为单一峰,获得了纯度较高的鳕鱼多肽,这为鳕鱼多肽的开发利用提供了科学理论依据.     

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