里氏木霉固体发酵生产纤维素酶的研究

以里氏木霉突变株ＲＭ－２７为纤维素酶生产菌，采用固体发酵法，２９℃发酵１４４小时，其滤纸酶活和β－葡萄糖苷酶活分别为６００ｍｇ和１１５ｍｇ葡萄糖／ｇＤＭｈ。并系统研究了各种营养成份和培养条件对ＲＭ－２７菌株产纤维素酶的影响。最适发酵培养基为稻草杆或小麦杆７０ｇ、麸皮３０ｇ、硫酸铵３．０ｇ、玉米浆２．０ｇ，水２００ｍｌ，自然ｐＨ。酶反应最适温度６０￣６５℃，最适ｐＨ为５．０。酶ｐＨ稳定性较好，在ｐＨ     

小麦多酚氧化酶酶学特性的研究

选取3个小麦品种作为试验材料,以邻苯二酚为底物,采用分光光度法在410nm处测定小麦多酚氧化酶（PPO）的活性,研究温度、pH值、底物浓度对其活性的影响以及酶促动力学常数Km,结果表明：小麦多酚氧化酶的最适温度范围为60～75℃．最适pH值为4．0～4．6,描述的单底物酶促反应动力学,相应的动力学参数Km=0．19mol／L．vmax=4．04×102（mol·L^-1）·min-1。     

啤酒小麦木聚糖酶酶学性质的研究

通过DNS法测定小麦木聚糖酶酶促反应的最适条件。结果表明:小麦木聚糖酶酶促反应的最适温度是50℃,最适pH是5.5~6.0,最适底物浓度是1.0000%,最适底物与酶液用量比例为9/1,最适反应时间为5-9min。     

脂肪酶固定化工艺

研究了以纸纤维素为载体,对－β－硫酸酯乙砜基苯胺（ＳＥＳＡ）为活化剂共价偶联法固定化脂肪酶的最适条件及固定化酶的稳定性。结果表明：醚化反应最适ｐＨ为１０．０,偶联最适条件为ｐＨ８．０,酶量控制在８００μｍｏｌ／（ｍｉｎ·ｇ）,所获得固定化脂肪酶具有较高的酶活和酶回收率,且有较好的稳定性,其半衰期为３７５ｈ．     

短小杆菌酶促合成二肽甜味剂Aspartame

研究多种因素对短小杆菌酶催化Ｌ－天冬氨酸（Ｌ－Ａｓｐ）和Ｌ－苯丙氨酸甲酯（Ｌ－ＰｈｅＯＭｅ）合成二肽甜味剂Ａｓｐａｒｔａｍｅ能力的影响。结果表明，反应最适ｐＨ为６．０，最适温度为４０℃，反应１０ｈ，催化能力为０．４７５ｇＡＰＭ／ｇ菌体，产率８０．５％，收率８１．０５％。     

几丁质固定化无花果蛋白酶的研究

载体几丁质通过甲酸和戊二醛活化共价偶联无花果蛋白酶，固定化反应在给酶量为１．０ｍｇ／ｇ载体，ｐＨ７．５，４℃进行１５ｈ。制备的固定化酶表观Ｋｍ值（酪蛋白）为０．９５ｍｇ／ｍｌ，溶液酶的Ｋｍ值为０．３８ｍｇ／ｍｌ，固定化酶的最适ｐＨ范围变宽，由溶液酶的最适ｐＨ７．５－７．８变为在ｐＨ６－８范围内酶活性保持稳定；固定化酶的最适温度由溶液酶的６０℃变为３７℃。重复水解酪蛋白７次后，固定化酶保持原酶活性５     

微生物转谷氨酰胺酶催化大豆11S球蛋白聚合研究

研究了微生物转谷氨酰胺酶（MtGase）催化大豆11S球蛋白的聚合反应条件。研究显示，TGase对11S的不同亚基反应不一样，它只能催化11S酸性亚基聚合，而碱性亚基几乎不受影响。离子强度I＝0．1时TGase催化活性要高于I＝0．5，这可能是酶海性受离子强度的影响。酶浓度范围为10－40U/g对TGase催化11S酸性亚基影响不大。TGase催化11S聚合的最适pH为7．0－8．0，pH过高或过低都不利于该酶反应。而在低于50℃范围内，温度越高TGase催化11S聚合越快达到平衡，37℃反应4h与50℃反应2h聚合效果差不多，而60℃已使TGase几利完全失活。     

节杆菌产β-呋喃果糖苷酶的性质研究

本文研究了节杆菌产β－呋喃果糖苷酶几方面的性质。该酶表现总活力的最适温度为35℃，最适pH为6．5；表现转移活力的适宜温度为42℃，最适pH为7．0。该酶以蔗糖与乳糖混合物为底物表现出最高的转移活力。     

菠萝蛋白酶应用的性质研究

本文研究了pH、温度、金属离子、EDTA、还原剂对菠萝蛋白酶单宁复合物酶促反应速度的影响，结果表明，该酶的最适pH为7．1，最稳定的pH范围为3．9－4．2，最适反应温度为55℃，一般的金属盐NaCl、kCl对酶反应影响不大，MgCl2、CaCl2在高浓度下对酶有一定程度的抑制作用，在低浓度下影响不显著，半胱氨酸在一定浓度的范围内，对酶反应速度有促进作用。DETA本身对菠萝蛋白酶没有激活作用，它能鳌合酶反应所需的金属离子，使酶活降低。     

饲用β—葡聚糖酶固体发酵的研究

研究了黑曲霉Ｇ－４１５固体发酵中碳氮比例，无机氮源，大麦粉及发酵时间对β－葡萄糖酶酶产量的影响，该菌在２８℃培养５０ｈ，β－葡聚糖酶活力可达６２６８８ｕ／ｇ（干曲），酶最适反应温度４０℃，最适ｐＨ５．５。     

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