柱色谱分离纯化五倍子没食子酸

目的:优化筛选分离纯化五倍子没食子酸的最优树脂及其工艺参数。方法:以五倍子水提取液为原料,比较NKA-2、LS303、HZ816、HP-20、XAD-16、HPD700、HPD500、S-8、AB-8、D101、D301 11种树脂对五倍子没食子酸的静态吸附与解吸效果,筛选最优树脂。采用单因素试验、正交试验与验证性试验,优化最优树脂动态吸附与解吸五倍子没食子酸的工艺参数。结果:NKA-2树脂为最优树脂,静态吸附量与解吸率分别达到94.856 mg/g和89.64%;当主要考虑没食子酸纯度时,其最优动态吸附与解吸工艺参数是:上样质量浓度7 mg/m L,上样体积7BV,上样流速2 BV/h,洗脱剂乙醇体积分数70%,洗脱体积2.5 BV,洗脱流速3 BV/h,所获五倍子没食子酸的纯度、得率分别为90.97%和78.84%;当主要考虑没食子酸得率时,最优动态吸附与解吸工艺参数为上样质量浓度5 mg/mL,上样体积5 BV,流速3 BV/h,洗脱剂乙醇体积分数70%,洗脱体积2.5 BV,洗脱流速2 BV/h,所获五倍子没食子酸的得率、纯度分别为85.04%和87.10%。结论:NKA-2大孔吸附树脂是一种可应用于五倍子没食子酸分离纯化的较好树脂。     

大孔吸附树脂分离纯化茶叶籽饼粕中的茶皂素研究

目的对采用大孔吸附树脂法分离纯化茶叶籽饼粕中茶皂素的工艺进行优化,为进一步开发利用茶叶籽资源提供依据。方法以茶皂素吸附率与解吸率为指标,通过静态吸附与解吸实验筛选最优树脂。通过单因素实验、正交实验及验证性实验,优化最优树脂动态吸附与解吸茶皂素的工艺参数。结果D101树脂的静态吸附量与解吸率分别为142.974 mg/g和98.02%,为分离纯化料液中茶皂素的最优树脂;当主要考虑茶皂素得率时,其最优动态吸附与解吸工艺参数为上样质量浓度10 mg/m L、上样流速3 BV/h、上样体积6 BV、乙醇洗脱体积浓度80%、洗脱流速3 BV/h、洗脱剂体积5 BV,在该工艺参数条件下,茶皂素得率为74.25%,纯度为84.30%;当主要考虑茶皂素纯度时,最优动态吸附与解吸工艺参数为上样质量浓度10 mg/m L、上样流速4 BV/h、上样体积7 BV、乙醇洗脱体积浓度70%、洗脱流速3 BV/h、洗脱体积5 BV,在该工艺参数条件下,茶皂素纯度为97.7%,得率为72.04%。结论 D101大孔吸附树脂是一种可应用于茶叶籽饼粕中茶皂素分离纯化的较好树脂。     

大孔树脂分离纯化发酵液中虫草素的研究

采用大孔树脂富集纯化北冬虫夏草发酵液中的虫草素,通过比较发现6种大孔树脂中NKA-Ⅱ型大孔树脂对虫草素的吸附与解吸效果最好。静态和动态参数优化结果表明,NKA-Ⅱ型树脂纯化虫草素的最佳吸附平衡时间为6 h,解吸平衡时间为3 h。优化后的动态参数为:以1 BV/h流速上样吸附,体积分数10%乙醇除杂,70%乙醇以4 BV/h的流量洗脱。该工艺所得样品虫草素质量分数达35%,纯度提高了10倍,虫草素回收率达90%以上,经反复结晶后得到纯度大于98%的虫草素。     

大孔树脂分离纯化木二糖技术

木二糖是低聚木糖的重要组成部分。通过对S-Ca树脂、ZA-Ca树脂、分子筛、P-Ca树脂、Na+树脂、L-Na树脂对木二糖的静态吸附与解吸的比较,在筛选出一种具有较高吸附率与解吸量树脂的基础上,比较不同洗脱流速下不同体积分数乙醇梯度洗脱对木二糖洗脱量、纯度、得率的影响及最优流速下不同乙醇体积分数等梯度洗脱对木二糖洗脱量、纯度、得率的影响。结果表明, Na树脂是几种树脂中分离纯化木二糖的最佳树脂,最佳参数:流速为0.8 BV,经过2 BV的10%乙醇进行梯度洗脱的木二糖、总得率和总纯度分别为4.78 mg, 62.8%和5.7%。     

大孔吸附树脂分离纯化核桃壳总黄酮

通过比较5种大孔吸附树脂对核桃壳总黄酮的吸附解吸性能,筛选出NKA-9树脂较适合纯化核桃壳总黄酮,并对其进行动态吸附特性研究。所确定优化工艺参数为:上样浓度1.0 mg/mL,pH值5.0,上样流速1.0mL/min,5BV体积分数95%乙醇洗脱效果最佳。核桃壳粗提物中总黄酮纯度为3.58%,经NKA-9树脂纯化后总黄酮纯度为62.3%,回收率达88.9%。     

黑加仑多酚纯化工艺的研究

用80%乙醇(含0.1%乙酸)超声辅助提取黑加仑多酚(简写为BCP),比较五种大孔树脂对BCP的静态吸附和解吸能力,筛选出纯化BCP的最佳树脂;结果表明NKA-9为BCP纯化的最佳树脂,具有较好的吸附、解吸效果;对BCP的纯化动态吸附和洗脱条件进行研究;结果表明吸附BCP条件为上样液p H 3,质量浓度5 mg/m L、吸附流速2BV/h。解吸条件为解吸液洗脱液体积分数70%、解吸流速2 BV/h、解吸液所用体积为200 m L。     

大孔吸附树脂分离纯化苦荞总皂苷的研究

为优化大孔吸附树脂分离纯化苦荞总皂苷的工艺条件,通过静态吸附解吸实验筛选出适合分离纯化苦荞总皂苷的大孔吸附树脂SP700,其饱和吸附量为(25.241±0.590)mg皂苷/g树脂。研究了样液浓度、吸附时间对吸附容量的影响,乙醇体积分数对解吸得率的影响,并进行了动态实验,确定了SP700型大孔树脂分离纯化苦荞总皂苷的最佳工艺条件为:最佳上样浓度约0.586mg/m L,流速2BV/h,树脂比样液体积为1∶1,动态洗脱实验中,上样后用体积分数分别为50%和70%的乙醇溶液进行分段洗脱,洗脱流速为2BV/h,用量为2~3BV,洗脱得率最高可达到88.9%,洗脱液蒸干后所得固形物中皂苷含量较提取液固形物中皂苷含量提高了约2倍。     

大孔树脂纯化“双红”花青素研究

以"双红"山葡萄为原料,研究NKA-Ⅱ,NKA-9,AB-8,D-101和HPD-100 5种大孔树脂对"双红"花青素的纯化作用。通过静态-吸附解吸试验,筛选出D101树脂为最佳纯化材料,确定最佳吸附-解吸温度为25℃。D101树脂最佳动态吸附-解吸工艺参数为:25℃,上样浓度22.5 mg/m L,上样量8 BV,上样流速为2 m L/min,洗脱剂为75%乙醇-0.01%盐酸,洗脱流速2 m L/min,洗脱剂用量7 BV。该条件下,"双红"花青素纯度为27.78%±0.043%。     

樟树叶木脂素大孔吸附树脂纯化工艺优化

采用大孔吸附树脂纯化樟树叶醇提液中木脂素类化合物。通过对比6种大孔树脂对樟树叶中木脂素吸附-解吸效果,从中筛选一种最适大孔吸附树脂作为纯化材料,并研究上样浓度、上样流速、上样体积对大孔树脂吸附率的影响,以及洗脱剂浓度、洗脱流速、洗脱剂用量对大孔树脂解吸率的影响,通过正交试验优化大孔树脂纯化木脂素的工艺。试验结果表明,大孔树脂最佳吸附-解吸工艺条件为:7BV上样量、2.12mg/mL上样浓度、1.0 mL/min上样速率、80%乙醇洗脱剂、洗脱流速2BV/h,洗脱剂用量8BV,该条件下樟树叶中木脂素得率为66.68%,纯度为15.91%,表明该大孔树脂对于樟树叶中木脂素纯化效果较好。     

大孔树脂法纯化陕产重楼总皂苷工艺研究

研究陕产重楼中总皂苷利用大孔吸附树脂纯化的最优工艺。应用7种大孔吸附树脂吸附重楼中的总皂苷进行静态实验,筛选得到最佳树脂;通过动态实验确定最佳树脂对重楼总皂苷的纯化的最优工艺参数。结果表明,HPD-400A树脂纯化重楼总皂苷的效果最优,最优工艺条件为上样液质量浓度5mg/mL,上样量8BV,流速3BV/h,解吸流速2BV/h,解吸剂体积分数75%的乙醇,洗脱剂用量4BV,按此工艺条件制备的重楼总皂苷的含量为62.68%;Freundlich等温吸附模型可更好的描述树脂对重楼总皂苷的吸附,采用HPD-400A树脂分离纯化陕产重楼中的总皂苷效果较好。     

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