功能性双歧杆菌培养基的筛选与优化

对常用4种双歧杆菌培养基进行筛选,确定出产双歧杆菌高的基础培养基,采用正交试验通过改变碳源、添加低聚果糖pH的内源调节优化筛选出基础培养基.最佳培养基为在筛选出的基础培养基中加0.5%低聚果糖和1%碳酸钙.最佳培养基较筛选出的基础培养基双歧杆菌活菌数提高约8.1倍,培养时间缩短4h.双歧杆菌利用最佳培养基在37℃下厌氧培养20h,菌数可达8.9 × 109CFU/ml.     

双歧杆菌检测与鉴定技术进展

简述了双歧杆菌的特性、双歧制品种类、保健功效及双歧杆菌微生态调节剂在近年来的发展，重点论述了近几年双歧杆菌检测和鉴定技术发展；采用分子生物学方法对双歧杆菌进行鉴定，该方法将成为快速、可靠的鉴定方法；指出基本生理生化反应，鉴别培养基，选择结合分子生物学方法可对双歧杆菌进行属、种、株水平鉴定，为尽快制定双歧制品检测国际及双歧制品产业发展提供可靠依据。     

蒺藜提取液对长双歧杆菌及青春双歧杆菌生长的影响

以MRS培养基为对照,OD600及pH值为响应,研究了蒺藜提取液浓度对2株双歧杆菌——长双歧杆菌及青春双歧杆菌生长的影响.结果表明;蒺藜提取液能促进长双歧杆菌和青春双歧杆菌的生长,但最适浓度因菌而已,长双歧杆菌和青春双歧杆菌在MRS培养基中的最佳蒺藜提取液的加量分别为2.0％和1.5％,37℃培养18h后,培养液的OD600分别达到1.388和1.564.     

猪源双歧杆菌的分离纯化及初步鉴定

本研究选用双歧杆菌增殖培养基，从13d龄和30d龄未断奶健康仔猪肠道和粪便中分离纯化出双歧杆菌，进行了各种生理生化鉴定实验，对其进行了初步鉴定。     

绿豆和乳清蛋白水解物对双歧杆菌促生长条件的研究

对婴儿双歧(Bifidobacterium infantis)和两歧双歧杆菌(Bifidobacterium bifidum)的生长发育特性进行研究,在掌握双歧杆菌基本特性的基础上,以乳糖、乳清水解物和绿豆水解物为促生长因子,研究其对双歧杆菌的增殖影响.经过单因素和正交试验发现,乳清蛋白水解物和绿豆蛋白水解物对两种双歧杆菌都有显著的促生长作用.最佳培养基优化方案为:对婴儿双歧杆菌,在基础PTYG培养基基础上,添加1.5g/100mL的乳糖,40%的乳清蛋白水解物和40%的绿豆蛋白水解物;对两歧双歧杆菌,在基础PTYG培养基基础上添加0.5g/100mL的乳糖,40%的乳清蛋白水解物和40%的绿豆蛋白水解物.     

食品中双歧杆菌显色培养基的研制

双歧杆菌在肠道中的有益功能已受到人们的高度关注。为建立准确、快捷的双歧杆菌定性定量方法,我们以乳酸杆菌(LBS)琼脂为基础,添加能够抑制或促进双歧杆菌生长的物质,同时添加酶显色底物,通过正交试验,经方差分析,确定最佳配方,形成双歧杆菌显色培养基。研制的双歧杆菌显色培养基具有成本低、快速、特异性高、准确性好等优点,满足目前食品行业检测双歧杆菌的需求,为今后生产和研究提供理论依据。     

混合制剂中快速计数双歧杆菌鉴别培养基的研究

研制了一种混合制剂中快速计数双歧杆菌鉴别培养基。用添加X-Gal的改良MRS培养基和厌氧胶法对4种标准双歧杆菌(长双歧杆菌、短双歧杆菌、青春双歧杆菌、两歧双歧杆菌)和2种标准乳酸菌(保加利亚乳杆菌、嗜热链球菌)分别单独培养、混合培养,结果在X-Gal培养基上,双歧杆菌单独培养及与乳酸菌混合培养双歧杆菌均为白色菌落或浅蓝色菌落,而乳酸菌为蓝色菌落。结果表明,在X-Gal培养基上双歧杆菌和乳酸菌有明显的鉴别性,可用于双歧杆菌和乳酸菌混合制剂的菌落鉴别计数。     

选择性计数双歧杆菌培养基的效果比较

随着双歧杆菌基础研究和开发应用的迅速发展,双歧杆菌活菌计数方法越来越重要,实验目的是要选择1种适于选择性计数产品中双歧杆菌菌落数的培养基。主要采用菌落技术方法,比较了常用的8种选择性培养基对7种产品中双歧杆菌的选择性计数效果。结果表明,以改良MRS-X-Gal琼脂培养基上形成的双歧杆菌菌落数最高,且菌落特征明显,易于计数,是优选出的效果较好的选择性计数培养基。     

双歧汗菌检测与鉴定技术进展

简述了双歧杆菌的特性、双歧制品种类、保健功效及双歧杆菌微生态调节剂在近年来的发展,重点论述了近几年双歧杆菌检测和鉴定技术发展;采用分子生物学方法对双歧杆菌进行鉴定,该方法将成为快速、可靠的鉴定方法;指出基本生理生化反应,鉴别培养基,选择结合分子生物学方法可对双歧杆菌进行属、种、株水平鉴定,为尽快制定双歧制品检测国标及双歧制品产业发展提供可靠依据.     

短双歧杆菌增殖培养基的优化研究

本研究针对短双歧杆菌的营养需要,采用正交实验设计优化增殖培养基,结果表明,酵母膏是短双歧杆菌的显著影响因素, 最佳的优化培养基配比是酵母膏0.9%,胰蛋白胨0.6%,大豆蛋白胨0.6%,葡萄糖0.6%,双歧因子0.2%,生长因子10%.用经优化的增殖培养基配方测定短双歧杆菌的生长曲线及其pH的变化,确定该菌增殖培养的最适终止时间约为18h,此时平板菌落计数的菌数可高达1.5×1010cfu/ml.     

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