淀粉接枝共聚物微球的合成与降解研究

在反相悬浮体系中以K2S2O8-NaHSO3引发N,N'-亚甲基双丙烯酰胺与淀粉的接枝共聚,制备了淀粉接枝典聚物微球.用人工肠液对所得淀粉微球进行体外降解,运用FT-IR、SEM、粒度分析仪对微球及其降解产物进行了表征分析,用正交实验分析了合成因素对微球粒径的影响.结果表明:共聚物微球形态圆整,平均粒径50.2μm,微球中存在酰氨基结构.正交实验表明:N,N'-亚甲基双丙烯酰胺和油水比对微球的平均粒径影响较大;体外降解表明:微球在3～4 h内基本维持稳定聚合结构,之后降解迅速.     

载药淀粉微球酶促降解的可控制性研究

采用酶催化的方式对淀粉微球进行可控降解,通过控制淀粉微球合成过程及降解催化剂酶的组成等,实现对淀粉微球进行可控降解。利用红外光谱仪、扫描电子显微镜对淀粉微球降解产物进行表征。结果表明,酶催化淀粉微球降解的最佳条件为：在模拟胃液2＋肠液3（同时含有胃蛋白酶、胰酶和α-淀粉酶）中降解．合成过程中交联剂的用量为0．06mol／L。FTIIK和SEM表明,微球粒径逐渐减小,持续降解大约10h。     

交联淀粉微球的制备与载药性能研究

以可溶性淀粉为原料,Span-80和Tween-80为乳化剂,液体石蜡为油相,N,N＇-亚甲基双丙烯酰胺（MBAA）及环氧氯丙烷（ECH）为交联剂,硝酸铈铵（CAN）为引发剂,采用反相乳液法制备淀粉微球。试验应用正交优化设计,选择淀粉浓度、油水比、交联剂MBAA用量、乳化剂用量和引发剂用量5个因素为考察对象,对淀粉微球的制备条件进行了优化。利用红外光谱和粒度分析仪对产物进行了表征。以胭脂红为模型药物,研究淀粉微球的载药性能。     

淀粉微球对Fe2+离子吸附性能研究

以可溶性淀粉为原料,在反相悬浮体系中合成N,N′–亚甲基双丙烯酰胺交联淀粉微球(CSM)为载体。研究淀粉微球对Fe2+ 的吸附行为,利用红外(FT-IR)、扫描电镜(SEM)、X 射线衍射仪(XRD)对微球及其吸附产物进行表征,研究其吸附机理。结果表明：淀粉微球对Fe2+ 吸附等温线符合Langmuir 等温方程,对其吸附等温线进行拟合,相关性较好。在室温条件下,pH 值为4.5,对Fe2+ 的吸附时间为60min,最大吸附量为0.866mmol/g,得出吸附速率方程,吸附Fe2+ 后微球结晶度降低。     

交联玉米淀粉微球合成及其吸附性能研究

以N,N′–亚甲基双丙烯酰胺为交联剂,用反相悬浮法合成交联玉米淀粉微球(CSMs),运用红外、X射线衍射仪、电镜、粒度分析仪对产物进行表征分析,测定淀粉及淀粉微球吸附阴离子表面活性剂(SDS)后pH值与Zeta电位,研究两者吸附性差异。实验表明,合成淀粉微球大小均一、结构致密、表面粗糙、孔隙发育良好,粒径在30μm以下微球占83%;与淀粉相比,随交联度增加,淀粉微球溶解度、溶胀度下降,吸水量增加,淀粉微球与阴离子表面活性剂间存在比淀粉更强吸附作用,可作为一种良好吸附剂。     

可降解淀粉微球的性能研究

以可溶性淀粉为原料,反相乳液聚合法合成可降解淀粉微球,并测定了它的粒度分布、红外光谱、降解性、载药性等.结果表明：可降解淀粉微球的平均粒径为15.423μm,94%分布在1～50 μm,8 h后被淀粉酶降解11.72%～24.58%,淀粉微球具有很好的可降解性.     

较小粒径淀粉微球最佳合成条件的研究

以可溶性淀粉为原料,环氧氯丙烷为交联剂,Span60为乳化剂,大豆色拉油为油相,采用逆相悬浮交联聚合法合成淀粉微球。通过正交试验探讨了合成较小粒径淀粉微球的条件。结果表明,淀粉乳浓度对淀粉微球粒径影响最大,较小粒径淀粉微球合成的最佳条件为：淀粉乳浓度12％,水相用量5mL,乳化剂用量0,6g,交联剂用量3mL。并在最佳条件下利用超声波配合乳化,以得到粒径更小更均匀的淀粉微球。     

较小粒径淀粉微球最佳合成条件的研究

以可溶性淀粉为原料,环氧氯丙烷为交联剂,Span60为乳化剂,大豆色拉油为油相,采用逆相悬浮交联聚合法合成淀粉微球。通过正交试验探讨了合成较小粒径淀粉微球的条件。结果表明,淀粉乳浓度对淀粉微球粒径影响最大,较小粒径淀粉微球合成的最佳条件为：淀粉乳浓度12％,水相用量5mL,乳化剂用量0,6g,交联剂用量3mL。并在最佳条件下利用超声波配合乳化,以得到粒径更小更均匀的淀粉微球。     

阴离子淀粉微球对Cd~(2+)的吸附及动力学研究

以可溶性淀粉为原料,N,N′-亚甲基双丙烯酰胺(MBAA)为交联剂,采用反相悬浮聚合得到中性淀粉微球,再用Na3P3O9进行阴离子化得到阴离子淀粉微球,用红外光谱和扫描电镜对其进行表征分析。研究阴离子淀粉微球对Cd2+的吸附行为,考察了pH、时间等因素对其吸附率的影响。结果表明:阴离子淀粉微球对Hg2+的吸附行为既符合Langmuir等温吸附方程又符合Freundlich等温吸附方程;同时,分别采用拟一级模型和拟二级模型考察了吸附动力学,并计算了这些动力学模型的速率常数,实验数据和拟二级模型计算结果之间有较好的相关性。     

较小粒径阴离子淀粉微球合成工艺的研究

以可溶性淀粉为原料,采用反相悬浮法制备环氧氯丙烷交联淀粉微球,加入三聚磷酸钠进行二次交联聚合合成阴离子淀粉微球。通过单因素试验和Plackett-Burman试验确定乳化剂用量、交联剂的用量、反应时间、三聚磷酸钠用量4个主要因素对阴离子平均粒径的影响,根据中心组合设计原理采用四因素三水平的响应面分析法,获得了合成阴离子淀粉微球最小粒径的最佳工艺条件,每3g可溶性淀粉(烘干水分)的乳化剂用量为0.5g,交联剂用量为4.0ml,反应时间为1.008h,三聚磷酸钠用量为0.6g,经验证试验,最小阴离子淀粉平均粒径为30.27μm。     

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