响应面法优化油茶粕培养里氏木霉酶系活力条件及发酵工艺研究

以油茶粕为底物,对里氏木霉发酵进行培养,研究了油茶粕比例、微晶纤维素添加量、接种量和pH对里氏木霉纤维素酶活力的影响。在单因素实验的基础上,采用响应面分析,优化发酵条件为:油茶粕比例为8. 6%,微晶纤维素添加量为0. 93%,接种量为12. 48%,pH值为4. 9。在该条件下,羧甲基纤维素酶活力为8. 47 U/mL,微晶纤维素酶活力为9. 28 U/mL,纤维二糖酶活力为5. 05 U/mL,滤纸酶活力为5. 44 U/mL。     

复合菌系的构建及其对玉米秸秆预处理的研究

本文研究了芽孢杆菌T_(7.0)、黑曲霉Z_3~4和里氏木霉三株菌的产酶情况,并将其进行复合发酵,研究了复合菌的接种顺序、接种比例对酶活力的影响。以葡聚糖内切酶的活力(CMC酶活)和滤纸酶活力(FPA酶活)作为指标,利用解脂假丝酵母预处理玉米秸秆,对预处理秸秆的条件进行了优化。结果表明:复合菌的接种顺序为:同时接种黑曲霉Z_3~4与里氏木霉,12 h后再接种芽孢杆菌T_(7.0);接种比例是:黑曲霉Z_3~4:里氏木霉:芽孢杆菌T_(7.0)为2∶1∶2。解脂假丝酵母预处理秸秆的最优条件是:处理时间36 h、接种量2%、秸秆粉碎度30目。经过生物法对秸秆预处理以后,CMC酶活达到404.28 U/m L。     

混菌发酵水稻秸秆生产柠檬酸工艺的研究

研究了黄孢原毛平革菌、里氏木霉和黑曲霉共同发酵生产柠檬酸。首先以水稻秸秆中木质素、半纤维素和纤维素的降解率为参考指标,通过单因素试验和多因素正交试验考察黄孢原毛平革菌和里氏木霉对水稻秸秆的降解情况,最佳的结果:初始pH为4.0,黄孢原毛平革菌和里氏木霉的比例为1∶5,黄孢原毛平革菌和里氏木霉的复合接种量为18%,最佳的发酵降解时间140h。然后接种黑曲霉,以柠檬酸的产量为参考指标,通过单因素试验和多因素正交试验考察黑曲霉发酵情况,最佳结果:初始pH为4.0,黑曲霉的接种量为15%,最佳的发酵降解时间140h,柠檬酸的产量达到79.83g·L~(-1)。     

里氏木霉与黑曲霉混合发酵产纤维素酶的条件优化

为提高纤维素酶酶解秸秆产糖效果,以碱性双氧水处理过的玉米秸秆为发酵基质,进行里氏木霉与黑曲霉混合发酵的研究。通过单因素试验确定黑曲霉延迟接种时间、里氏木霉与黑曲霉接种比例 、发酵时间和固液比4个因素的最优水平。在此基础上,采用Box-Behnken响应面设计对混合发酵产酶条件进行优化,获得最佳产酶条件：黑曲霉延迟接种时间 36h,里氏木霉与黑曲霉接种比例 5:1、发酵时间7d、固液比2:50(m/V)、吐温-80体积分数0.4%、pH 5.0和装液量50mL/250mL。此时,滤纸酶力(FPA)可达1.224 IU/mL,β-葡萄糖苷酶活力(β-GA)可达0.315 IU/mL。采用高效液相色谱法,对最佳条件下的纤维素酶酶解秸秆的水解液进行检测。结果表明,两菌株混合发酵较单菌株发酵的纤维素酶系更加完整,且降解木质纤维素类原料产可发酵性糖的能力增强。     

复合菌系的构建及其对玉米秸秆预处理的研究

本文研究了芽孢杆菌T_7.0、黑曲霉Z₃⁴和里氏木霉三株菌的产酶情况,并将其进行复合发酵,研究了复合菌的接种顺序、接种比例对酶活力的影响。以葡聚糖内切酶的活力（CMC酶活）和滤纸酶活力（FPA酶活）作为指标,利用解脂假丝酵母预处理玉米秸秆,对预处理秸秆的条件进行了优化。结果表明:复合菌的接种顺序为:同时接种黑曲霉Z₃⁴与里氏木霉,12 h后再接种芽孢杆菌T_7.0;接种比例是:黑曲霉Z₃⁴:里氏木霉:芽孢杆菌T_7.0为2∶1∶2。解脂假丝酵母预处理秸秆的最优条件是:处理时间36 h、接种量2%、秸秆粉碎度30目。经过生物法对秸秆预处理以后,CMC酶活达到404.28 U/m L。      

花生粕固态发酵生产高蛋白饲料菌种的筛选

选用产朊假丝酵母、热带假丝酵母、酿酒酵母、米曲霉、黑曲霉、康宁木霉、绿色木霉、里氏木霉对花生粕进行混菌固态发酵实验,以各组合发酵产物粗蛋白含量及回收率为指标,筛选出最佳菌种组合。结果表明,绿色木霉、米曲霉和酿酒酵母(接种比例为1∶1∶1)为最佳菌种组合,其发酵产物的粗蛋白含量为61.63%,显著高于未发酵的花生粕中粗蛋白含量,且通过氨基酸分析发现,发酵产物的营养价值也相应提高。     

粗壮脉纹胞菌复合多菌种发酵茶粕产纤维素酶的研究

用粗壮脉纹胞菌分别复合东方伊莎酵母、里氏木霉、绿色木霉、乳酸杆菌固态发酵已去除茶皂素的茶粕,通过测定发酵产物中3种纤维素酶：外切葡聚糖酶（C1）、内切葡聚糖酶（Cx）、β-葡萄糖苷酶（β-G）及总酶滤纸酶（filter paper activity,FPA）的酶活力来探讨其分解粗纤维素的协同作用。粗壮脉纹胞菌和绿色木霉混合发酵产生的C1酶酶活力较粗壮脉纹胞菌单菌发酵提高了51.09%,粗壮脉纹胞菌和绿色木霉复合发酵较单菌发酵延长了其纤维素酶分泌的周期,96 h时FPA酶活力达到2.782 U/g;粗壮脉纹胞菌复合里氏木霉、绿色木霉混合发酵组在发酵10 d后对茶粕粗纤维的最终降解率分别达到了64.19%和61.59%;接种量对单菌和混合菌发酵产纤维素酶影响总体趋势是随着接种量增加酶活力提高,但粗壮脉纹胞菌单菌发酵纤维素酶酶活力在接种量超过9 mL/100 g后开始下降。表明粗壮脉纹胞菌复合里氏木霉、绿色木霉混合发酵降解纤维素具有协同作用。     

油茶饼粕发酵条件的研究

以油茶饼粕和血粉为主要原料,以黑曲霉、米曲霉、绿色木霉和产朊假丝酵母组成的混合菌种为发酵剂,研究了油茶饼粕进行菌体蛋白饲料生物转化时发酵条件和培养基原料配比对发酵产物菌体干重的影响.通过正交实验,确定最佳培养基配比为:m茶粕:m血粉＝17:3,m料:V水＝1:1.2,初始pH为5.0～5.5;最佳发酵条件为:250 mL三角瓶,装料量15 g,总接种量10%,其中霉菌与酵母菌的接种比为1:1,培养时间为4 d.在最佳培养基和发酵条件下,得到的菌体干重为一最大值21.25 g/L.     

绿色木霉与黑曲霉混合发酵产纤维素酶的研究

为提高绿色木霉与黑曲霉混合发酵产纤维素酶的能力,进行了黑曲霉接种时间和混合发酵时间的优化。研究了绿色木霉与黑曲霉4株菌单独发酵及混合发酵产纤维素酶酶活的特点,调整黑曲霉NH11-1的接种时间与绿色木霉NM01进行混合发酵来寻找产酶能力最高的时间点。结果表明,黑曲霉NH11-1推迟48 h接种的混合发酵组产酶效果最佳。最佳混合发酵条件为30 ℃、200 r/min恒温振荡培养5 d,滤纸酶活力（FPA）达到242.80 U/mL,是出发菌黑曲霉NH11-1的2.66倍;β-葡萄糖苷酶活力（β-GA）达到297.35 U/mL,是出发菌绿色木霉NM01的1.94倍;β-GA与FPA的比值为1.22,符合纤维素酶水解天然纤维素的最佳比值范围（0.12～1.50）。     

发酵法制备小麦麸皮膳食纤维

通过微生物发酵降解、转化和利用小麦麸皮中的纤维素、蛋白质和淀粉等,可以制备高品质膳食纤维(DF)。以可溶性膳食纤维(SDF)作为主要考察指标,分别采用米根霉、黑曲霉及里氏木霉发酵小麦麸皮制备DF,考察单一菌种及混菌发酵后麸皮DF主要组分的变化,并对混菌发酵条件进行正交试验设计优化研究。结果表明：混菌发酵效果优于单一菌种发酵效果;当发酵条件为料液比1:10、里氏木霉和黑曲霉(1:1)混菌接种量10%、发酵温度32℃时,SDF含量达到了11.74%,提高了86.94%,所得产品持水力及溶胀性分别为9.34g/g和12.46mL/g,符合高品质膳食纤维指标要求。     

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