产酸性果胶酶菌株的筛选及产酶条件的研究

从实验室保藏的9株黑曲霉菌株和1株宇佐美曲霉菌株中，通过初筛和复筛获得了一株高产酸性果胶酶菌株一宇佐美曲霉（Aspergillus usamii）YL-1。YL-1菌株产酶发酵条件为：29℃静置培养72h，期间在24h翻曲1次。采用单因素试验确定了该茵株固态发酵优化培养基组成为：250mL锥形瓶装发酵基料10g（麸皮8g＋豆饼粉2g），食用果胶0．9g，玉米浆0．5mL，吐温-800．15％，（NH4）2SO4 2．0％，KH2PO40．4％（均相对于基料），料水比1：1，自然pH。酸性果胶酶活力最高达4831 IU／g干曲。     

真菌α-淀粉酶产生菌的筛选及酶学特性的研究

通过对实验室中保藏4种真菌菌株进行液体发酵与固体发酵研究，筛选出最佳的α-淀粉酶产生菌米曲霉FSO179，固体发酵产酶水平为910．3u／g，液体产酶水平为656.6u／mL。该酶酶学特性研究表明：该酶作用的最适温度为55℃，50℃保温30min仍保留80％；最适作用pH为4．0，pH稳定范围为3.5-6.0之间。Fe^2＋、Ba^2＋、Cu^2＋、Mn^2＋、Fe^3＋金属离子对酶具较强抑制作用。而Ca^2＋对酶具有一定激活作用。     

康氏木霉木聚糖酶酶学性质的研究

对1株康氏木霉（Trichoderma Koningii）发酵产木聚糖酶的酶学性质进行了研究。结果表明：该木聚糖酶的最适反应温度为65℃，酶反应最适反应pH为6．0；该酶在20-60℃范围内能保持80％以上的酶活，在pH3．0-10．0的范围内能保持85％以上的酶活；金属离子Ba^2＋、Fd^2＋、Al^3＋，12mmol／L的Cu^2＋和Fe^3＋对木聚糖酶的活性有抑制作用，而Ca^2＋，Zn^2＋和4mmol／L Cu^2＋等金属离子对该酶反应则有促进作用。     

青霉P-1007酸性蛋白酶酶学性质及其固体发酵条件的初步研究

青霉P-1007产胞外酸性蛋白酶，其酶活可达1500u／g。该酶的最适温度为50℃，最适pH值为5．5；酶的pH稳定性和耐温性较好，在pH5．5，：50℃条件下保温8h，其相对酶活仍在83％以上；在pH值为5．5，60℃条件下水浴2h后，相对酶活为60％。不同金属盐对该酶酶活及不同氮源、碳源、温度、pH、含水量以及发酵时间对菌株产酶的影响试验结果表明：MnCl2，CuSO4均对该酶有激活作用，其他金属盐类对该酶有不同程度的抑制作用；添加黄豆粉（1％）和葡萄糖（1％）可使菌株产酶酶活分别提高71％和31％；培养温度为40℃以及培养基起始pH为7．0时产酶最高；含水量和发酵时间对产酶也有不同程度的影响。     

黑曲霉胞外果胶酶特性的研究

对筛选出的A.niger A-03菌种产果胶酶的一些酶学性质进行了研究。结果表明：最适温度为50℃～55℃，随着温度的升高，酶的热稳定性下降；最适pH为4．0，果胶酶活力稳定的pH范围为3．5～4．5；最适盐浓度为0．2mol/L；Km值为147.1mg/mL；最大反应速度Vmax为19.2mg／min／mL；Ca^2 、AI^3 对果胶酶有激活作用，Hg 、Cu^2 对果胶酶有抑制作用。     

壳聚糖酶高产菌株的筛选、产酶条件的优化及壳聚糖酶的分离纯化

从采集的土样中分离到3株产壳聚糖酶的菌株，经摇瓶复筛，菌株JH01产酶能力最强。对其发酵产酶条件的研究结果表明其产酶最适培养基组分为：壳聚糖2．0%，NaCl0．05％，MgSO4 0．05％，KH2PO4 0．075％，FeSO4 0．001％，牛肉膏0．3％，pH5．5。最适产酶培养条件为：40℃、180r／min培养48h。在最适产酶培养条件下，48h时菌株JH01发酵液中壳聚糖酶活力可达到26．03U／mL，产酶能力为国内已报道的最高值。经DEAE Cellulose52柱层析，壳聚糖酶被纯化了11．70倍。经SDS—PAGE鉴定，纯化后酶已达到电泳纯的程度，分子量为30kD。     

出芽短梗霉XYE-7木聚糖酶的酶学性质

用固体平板法从果园土壤中分离出一株产木聚糖酶活力较高的类酵母真菌出芽短梗霉XYE-7。此茵的最佳产酶条件为：硫酸铵0．5％、0．2％的酵母膏、磷酸二氢钾0．1％、硫酸镬0．05％、木聚糖0．5％，初始pH值2．0，最适产酶温度是35℃，培养72h后发酵液酶活最高。该酶作用的最适温度是70℃，最适pH值为7．0。     

肉桂色曲霉9824饲用酸性蛋白酶的产生、性质及应用研究

本文对肉桂色曲霉9824菌株酸性蛋白酶产酶条件，酶学性质和在断奶仔猪的喂养效果进行了研究。结果表明，采用麸皮与豆饼比例6：4，氯化铵浓度1．5％，物料加水比1：1，菌株接种量0．3％，经66h发酵，其产酶活较高，该酶最适酸碱度pH3.0，最适作用温度为40℃，用pH4．0的乳酸缓冲液在50℃下提酶较完全。该酶具有较好的热稳定性，在100℃，1h可保持80％的酶活力。小鼠急性毒性试验证明该酶安全无毒。以0．1％添加到当地饲喂秧藤粉的断奶仔猪日粮中，经40d喂养，试验组比对照组日增重和饲料转化率分别提高13．2％和2．4％，并有效地控制了腹泻。     

产酸性果胶酶菌株的筛选及固体发酵工艺条件和酶水解特性的研究

本研究从土壤中分离筛选到一株产酸性果胶酶的菌株WY9,经分子生物学鉴定,菌株WY9初步鉴定为棘孢曲霉(Aspergillus aculeatus)。该菌株的最适固体发酵工艺条件为:发酵基料为玉米胚芽粕,每克基料添加NH_4H_2PO_40.06g、Mg_SO_40.04g,发酵基料含水量为65%,pH值为3,发酵温度为30℃,发酵时间为84h,在此条件下酸性果胶酶酶活达2200U/g干曲。该酶水解果胶的最适温度为50℃,最适pH为3.5,在温度低于60℃和pH2.5～4.5之间具有良好的稳定性。     

黑曲霉SL2-111固态发酵生产聚半乳糖醛酸酶

以麸皮为主要原料，采用黑曲霉(Aspergillus niger)诱变菌株SL2—111进行聚半乳糖醛酸酶固态发酵，培养物最高酶活力可达到2695u／g(鲜曲)。产酶最适培养基为：麸皮15g，柚皮粉1．5g，(NH4)2SO4 0．8g，Ca—Cl2 0.075g。最佳产酶条件为：28℃，pH6．0，培养72h。成曲的最佳浸提条件为：以0．1mol／L，pH4．0柠檬酸柠檬酸钠缓冲液为浸提剂，在30℃下浸提5h。     

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