硒对常见蔬菜种子萌发的影响及在植株中的分布

分析不同质量浓度的Na2SeO3对蔬菜种子萌发的影响及硒在蔬菜不同器官中的分布,采用种子萌发实验和盆栽实验,应用氢化物发生-原子荧光法测定总硒,透析法分析有机硒。结果表明：随着Na2SeO3质量浓度的升高,蔬菜种子的发芽势、发芽率、简易活力指数、发芽指数均呈先上升后下降的趋势,但个体之间存在一定差异。绿豆在2.5 mg/L的处理液条件下各项活力指标达到最好,但随着Na2SeO3质量浓度升高,其各项指标开始下降。蔬菜植株中总硒含量随着浇灌液中Na2SeO3质量浓度的增加呈明显的上升趋势,在10.0 mg/L的高硒环境下对硒的富集能力为：上海青＞快菜＞茄子＞辣椒＞西红柿。茄子、辣椒、西红柿3 种蔬菜不同部位中硒含量分布存在显著差异,其中m（有机硒）≥1/2m（总硒）。实验结果可为筛选最适宜水培液中Na2SeO3质量浓度和选择适宜培育的富硒蔬菜种类,以及选择硒含量高的部位进食提供理论依据。     

大豆发芽期间硒富集能力

采用亚硒酸钠(Na2SeO3)溶液浸泡-去离子水喷淋培养的方式,研究东北及江苏大豆品种发芽富硒情况。结果表明:在30mg/L Na2SeO3溶液中,25℃恒温浸泡6h富硒发芽条件下,不同品种大豆对硒的耐受能力及其富集能力差异显著,东北大豆-NJ的生长特性最好、富硒量最高。随着Na2SeO3浸泡液的质量浓度、温度的升高和浸泡时间的延长,该优选品种豆芽中总硒含量呈增加趋势。     

曲酒丢糟培养白地霉生产富硒饲料蛋白的研究

将白地霉接种在添加亚硒酸钠的培养液中进行驯化,以大曲丢糟为主要原料,以富硒白地霉为菌种,适当添加纤维素酶进行富硒饲料蛋白的发酵生产,通过正交试验得到最佳的饲料生产工艺条件为:Na2SeO3添加量为0.50 mg/kg,富硒白地霉接种量为15%,纤维素酶添加量为0.03%,培养时间4 d.所生产得的富硒饲料粗蛋白和有机硒含量分别达到了18.9%、0.18 mg/kg.     

高硒浓度下两种螺旋藻对Se(IV)的吸收和代谢

对极大(S.maxima)和钝顶(S.platensis)两种螺旋藻在接种后第5d和第6d两天内添加Na2SeO3(累计加硒浓度分别为600、800和1000mg/L),获得了有机硒含量分别为474.37、562.93、645.98μg/g(DW)的S.maxima和352.68、501.85、1198.15μg/g(DW)的S.platensis。分别测定了螺旋藻藻体及培养液中的无机硒、有机硒和总硒含量,分析了无机Se(IV)经螺旋藻吸收、代谢后的分布状况。     

青稞籽粒富硒发芽条件优化及其抗氧化能力分析

采用响应面法研究发芽时间、培养液pH和亚硒酸钠浓度对青稞籽粒中有机硒含量的影响,得到最佳富硒发芽工艺条件。在此条件下,进一步对青稞籽粒发芽过程中抗氧化物质含量及抗氧化能力进行分析。结果表明:青稞籽粒最佳富硒发芽工艺为发芽时间48.00 h、pH6.00、亚硒酸钠浓度10.00 mg/L,在此条件下,青稞籽粒有机硒含量为1.572 mg/kg DW,为原料的17.46倍。富硒发芽可显著提高青稞籽粒中总酚、总黄酮醇、有机硒含量以及ABTS+自由基清除能力(p<0.05),尽管降低了β-葡聚糖含量及铁离子还原能力(FRAP),但与未富硒组相比,富硒可有效延缓β-葡聚糖降解。相关性分析表明,总酚含量与有机硒含量、ABTS+自由基清除能力,β-葡聚糖含量与铁离子还原能力(FRAP)以及有机硒含量与ABTS+自由基清除能力均呈极显著正相关(p<0.01),其他指标间呈负相关或不相关。本研究表明,富硒处理可增加发芽青稞籽粒抗氧化物质含量,有效延缓β-葡聚糖降解,增强其抗氧化能力。     

发芽糙米的富硒及其微波干燥与挤压膨化工艺优化

以普通粳稻为原料,探讨了发芽糙米的富硒效果和微波干燥、挤压膨化对富硒发芽糙米营养品质的影响。结果发现,硒质量浓度为10 mg/L时,可以获得较高质量的富硒发芽糙米,此条件下糙米的发芽率为97.9%,有机硒含量为977.6 μg/kg（质量分数98.5%）,γ-氨基丁酸含量为445.9 mg/kg;40 ℃的低温微波干燥有利于保持发芽糙米的硒和γ-氨基丁酸含量;挤压膨化产品中有机硒和γ-氨基丁酸的含量与原糙米相比,分别提高到其29 倍和5 倍。研究认为,亚硒酸钠可以作为富硒试剂实现发芽糙米的有效富硒,富硒发芽糙米可以用于开发相关的营养膨化食品。     

极大螺旋藻的硒富集化培养研究

为得到大量含有机硒的极大螺旋藻(Spirulina maxima),以生物量和藻体内硒富集量作为指标,研究不同硒添加量和硒添加方式对极大螺旋藻生长及富硒效果的影响。结果表明,分8d等量(100μL)多次添加100μg/mL Na2SeO3溶液,是最佳添加量和添加方式,可得到生物量为0.903g/L,单位干藻粉有机硒含量为1413.168μg/g的富硒极大螺旋藻。     

硒添加方法对螺旋藻生长及富集转化硒的影响

本文比较了在标准培养液中不同硒添加方法对钝顶螺旋藻生长及富集转化硒的影响。结果表明,于培养液中加入低浓度Na2SeO3（50μg／ml）培养,第五天将藻液浓缩5倍后再添加Na2SeO3,使浓缩藻液中Na2SeO3浓度达到400μg／ml,继续培养3天采收,可获得有机硒含量稳定在400μg／g藻粉左右水平的富硒螺旋藻,按该方式添加Na2SeO3对螺旋藻产率无明显影响。     

富硒蛹虫草中有机硒的分析

建立高分辨-连续光源石墨炉原子吸收光谱法(high resolution-continuum source graphite furnace atomic absorption spectrophotometry,HR-CS GFAAS)测定富硒蛹虫草中有机硒的方法。参照DBS42/002-2014《湖北省食品安全地方标准富有机硒食品硒含量要求》制备富硒蛹虫草总硒测定试样,参照GB 1903.21-2016《食品安全国家标准食品营养强化剂富硒酵母》制备富硒蛹虫草无机硒测定试样,再使用HR-CS GFAAS测定富硒蛹虫草总硒和无机硒。试验以Pd(NO_3)_2(1 g/L)和Mg(NO_3)_2(0.5 g/L)混合溶液为基体改进剂,通过试验优化出基体改进剂最佳添加体积为5μL,最佳灰化温度为1 100℃,最佳原子化温度为2 200℃。测定结果表明,富硒蛹虫草总硒含量为1.407 mg/g,无机硒含量为0.083 mg/g,计算出有机硒含量为1.324 mg/g,所占百分比为94.1%,这说明富硒蛹虫草含有丰富的有机硒,是补硒良品。总硒和无机硒的加标回收率分别为95.7%和94.0%,相对标准偏差4.5%。该方法快速、准确、稳定,具有较高的实用价值,为分析食品中微量元素含量及其形态提供科学依据。     

曲酒丢糟培养A地霉生产富硒饲料蛋白的研究

将白地霉接种在添加亚硒酸钠的培养液中进行驯化，以大曲丢糟为主要原料，以富硒白地霉为菌种，适当添加纤维素酶进行富硒饲料蛋白的发酵生产，通过正交试验得到最佳的饲料生产工艺条件为：Na2SeO3添加量为0．50mg／kg，富硒白地霉接种量为15％，纤维素酶添加量为0．03％，培养时间4d。所生产得的富硒饲料粗蛋白和有机硒含量分别达到了18．9％、0．18mg＆g。     

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.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

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