“食品和发酵工业用菌种安全问题”研究取得成果

食品和发酵工业是国民经济发展的重要支柱 ,食品和发酵工业用菌种的安全性关系到企业兴衰和广大消费者的生命安全。由中国疾病预防控制中心营养与食品安全所承担国家“十五”重大科技专项“食品安全专项”中的“工业用菌安全性的检测与评价技术的研究”课题进展顺利。该研究建立的工业用真菌菌种毒理检测技术能够合理、客观地评价工业用真菌菌种的安全性 ,改变了现有的只对菌种有毒代谢产物的毒性进行评价的不完整性。该研究还建立了检测红曲制品及红曲培养物中桔青霉素、黑曲霉代谢产物赭曲霉毒素Ａ ,米曲霉代谢产物———硝基丙酸的实验室…     

北京居民食用粮食中曲霉属菌种产毒能力分析

作者对1987～1988年北京居民食用粮食中分离的曲霉属5个种群—黄曲霉、杂色曲霉构巢曲霉、灰绿曲霉和赭曲霉共248株菌的产毒能力进行了测定。结果表明:所检测的5个种群除灰绿曲霉外其余4种均有产毒菌。这些菌分布于大米、小麦、面粉、玉米及玉米面和豆类五种粮食中。产黄曲霉毒素菌在上述五种粮食中均有检出,产毒菌比例分别为(%)8.42、9.09、18.75、15.38和20.83。产杂色曲霉毒素的菌有杂色曲霉8株、构巢曲霉3株。产毒率各为16.17%,8.82%。产赭曲霉毒素的赭曲霉只在大米中检出1株(9.09%)。比较各类产毒菌的产毒量,以杂色曲霉最高。8株菌中竟有3株为16万～40万 ppb 的极强毒株。产毒菌的检体污染率以大米最高为22.04%;平均产毒率也以大米较高(17.33%)作者建议在制定粮食霉菌限量标准时应考虑产毒霉菌的性能及数量。     

红曲黄酒酿造用曲真菌菌群分析

收集10种典型红曲(5种古田红曲和5种乌衣红曲),采用不基于培养的微生物分子生物学方法分析其真菌菌群结构。通过PCR-DGGE技术测定,结果表明相比于古田红曲,乌衣红曲具有更高的真菌丰度、多样性及均匀性。对DGGE电泳谱图通过主成分分析和聚类分析发现,古田红曲和乌衣红曲的真菌菌群结构具有显著性差异。通过qPCR技术对红曲黄酒酿造用曲中的优势真菌(红曲霉、黄曲霉、米根霉和酵母)进行定量分析,结果显示,古田红曲和乌衣红曲中红曲霉的平均菌量分别为(6.07±0.25)lg (CFU/g),(5.82±0.11)lg (CFU/g),两种红曲的红曲霉菌量无显著差异(P0.05)。古田红曲中黄曲霉的平均菌量为(5.94±1.04)lg (CFU/g),米根霉的平均菌量为(4.65±0.91)lg (CFU/g),酵母的平均菌量为(3.33±0.99)lg (CFU/g),而乌衣红曲中黄曲霉的平均菌量为(8.21±1.22)lg (CFU/g),米根霉的平均菌量为(6.71±1.27)lg (CFU/g),酵母的平均菌量为(5.41±0.44)lg(CFU/g),这3类优势真菌在两种红曲中都具有显著差异(P0.05)。综上所述,红曲具有一定的真菌多样性,其中红曲霉是其主要优势真菌;此外,乌衣红曲与古田红曲的真菌菌群结构具有明显差异,且真菌多样性更高。     

广东客家黄酒酒曲中微生物的初步鉴定及其产γ-氨基丁酸能力的研究

本文以广东客家黄酒酒曲为对象,对黄酒发酵用红曲、麦曲和酒药中的微生物进行分离,探讨了酒曲中微生物产γ-氨基丁酸(GABA)的能力。研究结果表明,从红曲中分离出2株真菌分离物,其中红曲霉1株和酵母1株;从麦曲中分离出7株真菌分离物,其中毛霉1株,曲霉4株,根霉1株和酵母1株;从酒药中分离出6株真菌分离物,其中根霉1株,曲霉4株和酵母1株。通过生化特性研究及序列分析,鉴定出麦曲的曲霉中有1株为米曲霉,酵母为酿酒酵母。将所分离出的菌株分别进行液态发酵,并采用高效液相色谱检测了发酵液中GABA的含量。研究结果显示,从红曲、麦曲和酒药中分离出来的真菌分离物都具有产GABA的能力,不同真菌分离物产GABA的能力不同。其中,根霉和几株曲霉发酵液中GABA含量较高,特别米曲霉,达到40 mg/L以上,毛霉产GABA含量次之,为34.22 mg/L,而酵母产GABA含量最少,为10 mg/L左右。     

三种曲霉菌之间的产毒干扰

田间和贮存条件下玉米样品受真菌和真菌毒素污染的区域性调查表明,在某些样品上同时发现了黄曲霉、棕曲霉和杂色曲霉三种毒菌,但是仅能检测出一种毒素。在实验条件下对这种现象进行研究,在液体察氏培养基和玉米上,将黄曲霉、棕曲霉和杂色曲霉单独培养,或者任两种或三种菌混合培养。结果是黄曲霉与棕色曲霉混合生长或黄曲霉与杂色曲霉混合生长时,仅产生黄曲霉毒素     

红曲霉合成莫纳克林K的研究进展

红曲霉是一种药食两用丝状真菌,广泛应用于食品、医药、生物催化等领域。莫纳克林K是红曲霉主要代谢功能活性产物,具有降脂、抗疲劳、抗菌、抗癌和保护神经等生物活性,是公认的降低胆固醇的理想药物。研究对比了红曲霉与土曲霉合成莫纳克林K基因簇的不同,阐述了红曲霉产莫纳克林K的合成途径;对莫纳克林K在医药和保健食品、饲料等领域中应用的情况和潜力进行了归纳和展望。由于天然红曲霉发酵产功能性物质过程中,伴随产生的真菌毒素桔霉素,对肾脏、肝脏、心脏和生殖系统有毒性影响,使红曲霉工业化发展受到限制。提高红曲霉的莫纳克林K产量,并降低桔霉素的产生,是解决功能红曲发展问题的重要途径。因此,从诱变育种、构建工程菌株、优化培养基、控制环境因子等方面总结了优选红曲霉高产莫纳克林K并避免桔霉素积累的技术方法。主要对红曲霉产莫纳克林K的合成途径、生物活性及应用领域、高产莫纳克林K的生物技术方法研究现状进行总结,在此基础上分析红曲霉产莫纳克林K中存在的问题,并提出建议与展望,以期为新型红曲保健食品的研究与开发提供理论依据和参考。     

湘派卤制品卤汁中黄曲霉毒素产毒菌的筛选鉴定及其产毒能力测定

以湘派卤制品卤汁为研究对象，对其贮存过程中产黄曲霉毒素的微生物(产毒菌)进行筛选鉴定并对产毒能力进行测定。采用平板稀释涂布法和紫外荧光法对湘派卤汁进行产毒菌的初筛；对初筛菌株的ITS序列进行PCR扩增、测序，测序结果经NCBI同源性对比、MEGA6.0软件构建系统发育树进行分子生物学鉴定；应用HPLC-MS/MS检测各产毒菌培养液中黄曲霉毒素(aflatoxin, AFs)含量，确定各产毒菌的产毒能力。经平板稀释涂布法、紫外荧光法和分子生物学共筛选鉴定出5株产毒菌株，其中有4株是黄曲霉(Aspergillus flavus),1株为寄生曲霉(Aspergillus parasiticus);经HPLC-MS/MS法确定4株黄曲霉均不产生AFs,寄生曲霉产生黄曲霉毒素B₁(AFB₁)和黄曲霉毒素G₁(AFG₁)。AFB₁在第3天和第7天的含量分别为6.92、8.08μg/L,AFG₁在第3天和第7天的含量分别为5.80、7.24μg/L;湘派卤汁由于贮存条件...     

不同液态发酵基质对红曲霉产红曲色素及桔霉素的影响

在前期分离纯化出的10株红曲霉基础上,以18种液体培养基对10株红曲霉进行发酵培养,通过分光光度计和质谱分析仪测 定各发酵液中红曲色素和桔霉素含量,分析不同地区红曲霉的红曲色素和桔霉素的代谢特性,筛选出高产红曲色素低产桔霉素的 红曲霉菌株。 结果表明,产红曲色素最适的液体培养基配方为葡萄糖3%、蛋白胨1%,其中新疆地区红曲霉所产红曲色素量最高,为 6.81×10-2 mg/mL;新疆地区红曲霉仅在18种培养基中的面筋碱性蛋白酶水解液+葡萄糖发酵液中产生了桔霉素,而红曲霉ZBX天津 在所有培养基发酵液中均未产生桔霉素。     

腐乳中存在的安全隐患

综述腐乳在其生产原料、微生物污染、菌种、红曲辅料、生产用水、食用期间等方面存在的安全隐患;对发酵食品的工业用菌可能造成的安全问题、红曲辅料中桔霉素残留及腐乳中红曲霉产桔霉素等安全性问题进行具体阐述.为腐乳的安全性研究提供理论依据和实践基础.     

不产毒黄曲霉菌对产毒黄曲霉菌产毒抑制效果分析

本实验6株菌分离自广东、山东、辽宁和湖北四省的花生土壤中,通过形态学和分子生物学鉴定均为黄曲霉菌,HPLC测定其产毒能力,其中GZ-6为产毒菌,GZ-15、WF-5、WF-20、JZ-2和YC-8为不产毒菌。分别以花生和玉米为培养基,将不产毒黄曲霉菌和产毒菌(孢子浓度:104:105或105:105)进行混合培养,测定不产毒菌对产毒黄曲霉产毒的抑制效果。结果显示:不产毒菌对产毒菌产毒的抑制率随着其孢子浓度的增加而明显加强,当孢子浓度比为105:105(不产毒菌:产毒菌)时,5株不产毒菌在玉米培养基上对产毒菌产毒的抑制率为34.55%~75.94%,在花生培养基上对产毒菌产毒的抑制率为38.03%~83.03%,其中WF-5、WF-20和GZ-15这三株不产毒菌对产毒黄曲霉产毒的抑制效果均达到75.00%以上,可以作为田间防治黄曲霉毒素污染的候选菌株。     

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