高效液相色谱测定水解大豆中异黄酮方法研究

该研究建立大豆提取物中大豆异黄酮高效液相色谱测定方法,通过正交实验确立糖苷型大豆异黄酮转化为游离型大豆异黄酮最佳酸水解工艺条件:盐酸浓度为2．0 mol/L,水解温度为80℃, 水解时间为1．5 h;采用ZorbaX 80A Extend-C18 4．6×150 mm 4 μm色谱柱,MeOH-1．8％冰乙酸水溶液(35:65,V／V)为流动相,MeOH 35％-50％梯度洗脱,流速1．0 ml/min,检测波长为260nm等色谱条件下测定甙元含量,并通过换算因子计算大豆异黄酮含量。     

HPLC法检测黑豆乙醇提取物中活性成分的含量

采用高效液相色谱技术（HPLC），建立快速、有效、能同时分析检测黑豆乙醇提取物中大豆苷、苷元、木苷、木素含量的检测方法。结果：在一定条件下流动相及其比例对各组分的分离测定有较大的影响，我们所确定的色谱条件为：固定相：C18柱，流动相：甲醇：水：乙酸为42：57：1，检测波长为260nm；标准对照品的浓度与吸收峰面积均有较好的线性关系，r〉0．99，各组分间分离度大于1．5；测得的黑豆乙醇提取物中大豆苷、染料木苷、大豆苷元、染料木素的平均含量（％）分别为：0．341、0．386、0．0929、0．0265。RSD（％）分别为3．49、5．12、10．0、4．94。HPLC法可同时检测黑豆提取物异黄酮中大豆苷、染料木苷、大豆苷元、染料木素的含量，而且方法简单、快速、精密度高、重现性好。     

HPLC法测定大豆提取物中大豆异黄酮含量的研究

主要建立了HPLC法测定大豆提取物中大豆异黄酮含量的方法。通过实验确定了HPLC法测定大豆提取物中大豆异黄酮的最佳条件是：采用Waters Symmetry5μmC18,250mm×4．6mm色谱柱;流速：1．0mL／min;波长260nm;柱温：35℃;流动相A为含0．1％（v/v）乙酸的乙腈溶液,流动相B为含0．1％（v／v）乙酸的超纯水溶液,流动相梯度：18％-35％N乙腈溶液。该方法灵敏度高、重现性好,回收率达98％,变异系数小于3％,为研究大豆异黄酮其它产品打下了良好的基础,操作方法简单,易于掌握。     

超声辅助提取大豆异黄酮的研究

比较了醇提法与超声及超声加搅拌辅助提取大豆异黄酮的效果。正交试验结果显示，当超声频率为25kHz、超声功率为160W、乙醇浓度为50％、料液比为1：6、60℃超声处理60min时，大豆异黄酮的得率和含量分别可达4．23mg／g和2．74％，与醇提法相比分别提高了3．93％和7．87％；采用相同条件下的超声加搅拌(300r／min)处理，大豆异黄酮得率可达4．36mg／g，与单纯超声辅助提取法相比提高了3．07％，但其含量有所下降。超声辅助提取法对大豆异黄酮的抗氧化活性无影响。     

米曲霉产大豆异黄酮糖苷酶发酵条件的研究

通过单因素实验和正交实验，探讨米曲霉O3产大豆异黄酮糖苷酶的最佳条件。结果表明：在培养基组分为玉米芯3％、豆饼粉0．2％、KH2PO40．4％、CaCI20．04％、MgSO4-7H2O 0．04％，自然pH，接种量为10％，培养温度为30℃，60h的条件下，米曲霉O3菌株的产酶活性较高，可达388．572U／mL。     

高效液相色谱法测定大豆异黄酮含量的研究

采用高效液相色谱 (HPLC)法对大豆异黄酮产品进行含量测定 ,是快捷、准确检测大豆异黄酮含量的方法。结果显示 ,确定标准样品Daidzin和Genistin作为检测大豆异黄酮的主要成分是有实验根据的 ,这两种成分占大豆异黄酮总量 95 %以上 ,可以代表总体样本。最佳的色谱条件为 :色谱柱VP -ODS(Φ4 .6mm× 15 0mm) ,流动相VMeOH:VHAc:VH2 O(4 0∶0 .5∶6 0 ) ,流速 1.5mL/min ,柱温 4 0℃ ,最适检测波长 2 5 4nm。     

大米中无机砷测定方法的优化改进

对大米中无机砷的提取和测定方法进行了优化改进,比较了国家标准GB 5009.11-2014中推荐流动相磷酸二氢铵(NH4H2PO4)与仪器推荐的磷酸氢二钠(Na2HPO4)和磷酸二氢钾(KH2PO4)混合流动相的分离效率;分析了1％硝酸(HNO3)、3％三氟乙酸(TFA)、10％甲醇(CH3OH)三种提取液对无机砷的提...     

大豆异黄酮酸水解工艺的研究探讨

通过正交实验确立了糖苷型大豆异黄酮转化为游离型大豆异黄酮的最佳酸水解工艺条件：盐酸甲醇溶液的浓度为2mol／L，水解温度为80℃，水解时间为60min。水解前样品中大豆异黄酮的含量为D：13．86％、G：23．48％、De：0．22％、Ge：0．02％，水解后样品中大豆异黄酮的含量为D：nd(未检出)、G：nd(未检出)、De：14．01％、Ge：23．45％，水解充分。     

高效液相色谱法测定大豆中异黄酮的含量

用高效液相色谱法测定了大豆中六种异黄酮成分,同时比较了不同浓度乙醇制备样品对含量测定的影响。结果显示大豆中极性异黄酮含量高,低极性异黄酮甙元含量低。测定大豆中异黄酮含量的乙醇浓度最好控制在60％-80％。色谱柱采用日本岛津公司的Shim-Pack CLC ODS柱(150×6．0mmID5μm),流动相为MeOHHACH2O（303.566.5),流速为0-8．5min时1．0ml／min,5．8-47min时1．5ml／min,柱温为50℃,检测波长为254。     

大豆粕功能性成分提取条件的研究

综述了大豆中各种活性成分的研究进展，并在综合利用的基础上对从大豆粕中提取分离大豆异黄酮和大豆皂甙的工艺条件进行了探讨。实验结果表明：以水为提取剂，料液比(质量浓度)1：10，在60～70℃下，浸提2～3h，异黄酮的回收率可达85％以上，蛋白质的提取率为2．55～3．07g／dL；采用95％过20目筛的细度即可得到满意的效果，异黄酮回收率可达90％，蛋白质收率2．95g／dL；异黄酮在大孔树脂和AB-8树脂吸附后，以质量分数20％～60％的乙醇为洗脱液，AB-8树脂的得率比大孔树脂高14.67％；收集水洗脱液可制取大豆低聚糖。     

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