连苯三酚改性的天然大分子和单宁酸配位交联水凝胶的研究进展

通过研究被囊动物的被膜伤口愈合机理,科学家们明确了连苯三酚结构在生物大分子交联中的作用。受此启发,人们开发出了基于配位交联的连苯三酚改性的天然大分子多功能水凝胶材料。同样地,含有连苯三酚结构的单宁酸也可通过配位交联形成多功能水凝胶材料。本文主要介绍了近年来连苯三酚结构修饰的壳聚糖、甲壳素等天然生物大分子,以及单宁酸通过其连苯三酚结构与金属离子发生配位交联,形成多功能水凝胶的研究进展。     

水凝胶基纳米复合材料在食品有害物电化学检测中的应用研究进展

水凝胶基纳米复合材料具有比表面积大、结构易于功能化、生物相容性好、易被集成到信号转导系统中等优点，是一种良好的电极修饰材料。总结了水凝胶基纳米复合材料几种常用的合成策略，讨论了水凝胶基纳米复合材料修饰电极的制备及其用于电化学检测的传感机制，对水凝胶基纳米复合材料的制备及其在电化学传感器中的应用进行了展望，对推动电化学传感检测技术的发展具有参考意义。     

蚕丝蛋白水凝胶的研究现状

通过介绍蚕丝蛋白水凝胶的制备方法、蚕丝蛋白水凝胶的凝胶成型机制、蚕丝蛋白水凝胶的改性处理、蚕丝蛋白水凝胶的力学性能以及蚕丝蛋白水凝胶的快速成型方法,并结合课题组对蚕丝蛋白水凝胶在三维生物打印方面的研究,较为系统地分析了各种蚕丝蛋白水凝胶制备方法的优劣和修饰改性的目的,并详细地阐明了蚕丝蛋白水凝胶的凝胶成型机制和快速凝胶成型方法,为进一步研制高质量的蚕丝蛋白水凝胶及其推动蚕丝蛋白水凝胶的产业化提供参考。     

适配体功能化的DNA水凝胶的制备及其在食品安全小分子快速检测中的应用

DNA水凝胶是具有三维聚合物网络的高保水性材料。研究人员设计了多种DNA水凝胶交联制备方法,并通过向其中引入其他功能分子或与其他类型的功能材料相互结合,构建了具有优异性能的DNA水凝胶,受到了广泛关注。适配体是基于指数富集的配体系统进化(systematicevolutionofligandsbyexponential enrichment,SELEX)技术从随机寡核苷酸文库中筛选获得的对目标物质具有良好特异性与亲和力的寡核苷酸序列。适配体功能化的DNA水凝胶具有靶向范围广、稳定性好、易于修饰、操作简单和成本低等优点,得到了广泛应用。本文概述了构建适配体功能化的DNA水凝胶的基本设计原则与分类,重点介绍了适配体功能化的DNA水凝胶在食品安全检测中的最新策略,最后,讨论了适配体功能化的DNA水凝胶面临的挑战以及对未来的展望,旨在为其在食品安全领域的应用提供参考。     

酶法修饰对大豆分离蛋白凝胶性质影响的研究进展

大豆分离蛋白（soybean protein isolate,SPI）具有高营养性和良好的功能特性,但是,采用“碱溶酸沉”的传统方法所获得SPI往往会发生部分变性,最终常会以热力学稳定的水不溶性大聚集体和/或沉淀形式出现,对其凝胶性能产生不利影响。在实际生产中为改善SPI的凝胶性质,可进行物理、化学改性或酶法修饰,其中物理和化学改性反应特异性低,难以控制蛋白变性程度;而酶法修饰手段因具有反应条件温和、产品得率高、生产过程安全等特点得到广泛关注。本文综述了不同酶法修饰手段对SPI凝胶形成及性能的影响,通过描述SPI热凝胶和冷凝胶的形成机制,讨论限制性酶解、酶诱导的侧链接枝反应以及酶诱导的交联反应对SPI凝胶形成的影响,并对酶法修饰SPI凝胶的开发应用进行展望。     

温敏性水凝胶的合成及棉织物透湿透气整理

以聚乙二醇和顺丁烯二酸酐为原料合成大分子双烯化合物,并将其作为交联剂制备具有网状立体结构的温敏性水凝胶聚N-异丙基丙烯酰胺(PNIPAM),通过轧-烘-焙方式将其整理到棉织物上。研究大分子双烯种类及用量对PNIPAM粒径和棉织物透湿、透气性能的影响。结果表明,PNIPAM能改善全棉织物温度可控下的透湿和透气行为,以MA-PEG600-MA为双烯交联化合物合成的温敏性水凝胶,其粒径和温度变化条件下的溶胀比最大,改善织物透湿和透气性能效果最佳。     

纤维素纳米纤丝基水凝胶及其在废水处理中的应用进展

纤维素纳米纤丝(CNF)作为一种来源丰富的可再生纳米材料,具有优异的机械性能、高比表面积及化学可修饰性等优点,采用物理或化学交联所制备的CNF基水凝胶具有较好的机械性能和溶胀率等,在工业废水处理领域具有良好的应用前景。本文主要介绍了纯CNF水凝胶和CNF纳米复合水凝胶的相应制备方法及性能,同时也介绍了其在工业废水中对染料或重金属离子吸附方面的应用进展,最后指出了CNF基水凝胶在废水处理应用中存在的问题及未来主要研究方向。     

用于有机磷农药检测的植物酯酶生物传感器的研究

报道了一种用于有机磷农药检测的电流型生物传感器.从小麦中提取植物酯酶,纯化后作为生物传感器的酶源,以CuTAPC/SWCNT/GC修饰电极为基体电极,采用气相沉积法制备TiO2凝胶,通过凝胶包埋法制备植物酯酶生物传感器.该传感器具有良好的稳定性和重现性.当对硫磷、辛硫磷和氧化乐果浓度分别在0.5×10-9～1×10-5、10-9～10-5、0.5 × 10-8～10-5 mol/L范围内时,抑制率与其浓度的对数呈线性关系,检测限分别为3.24×10-10、1.26×10-9、6.60×10-9mol/L.     

食品级凝胶颗粒的制备及应用研究进展

凝胶颗粒是具有颗粒形态的微凝胶大分子物质,由大分子聚合物交联形成,微观上具有三维网络结构。凝胶颗粒具有稳定的网络结构,可以分散在溶液中,在宏观上具有流体力学性质。凝胶颗粒的制备可通过挤压法、喷雾干燥法、剪切法以及高压均质法等机械方法对凝胶或胶体颗粒溶液进行分离、破碎,得到含有微米或纳米级凝胶颗粒的溶液。因其兼具凝胶性质和流体力学性质,故可以对功能因子进行包埋和保护。凝胶颗粒具有良好的稳定性,可以作为乳液中的稳定剂制成皮克林乳液。本文概述了凝胶颗粒的种类以及国内外几种常用的机械制备方法,简述了其目前在食品工业中的应用状况,为进一步研究凝胶颗粒在食品领域中的应用拓展奠定基础。     

氨基功能化有机-无机杂化介孔材料合成及药物释放性能研究

以1,2-二(三甲氧基硅基)乙烷(BTME)和3-氨基丙基三乙氧基硅烷(AMPTS)为前驱体,通过共缩聚的方法合成氨基修饰的乙烷桥联的有序介孔氧化硅,并对其进行表征;再以布洛芬为模型药物,将得到的材料用于药物的吸附与释放,研究其药物释放性能.结果表明,氨基修饰后的杂化介孔材料对布洛芬具有更强的吸附能力,从修饰前的0.35 g/g增加至0.78 g/g.与未修饰的材料EA—0相比,氨基功能的材料EA—20在释放过程中具有更好的缓释效果.     

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.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

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