藤茶多糖的抗氧化作用研究

目的: 探讨藤茶多糖的体内外抗氧化作用。 方法: (1)测定藤茶多糖(Ampelopsis Grossedentata polysaccharide,AGP)的还原能力;(2)测定AGP在化学模拟体系、体外血清的抗活性氧能力;(3)测定AGP对小鼠肝匀浆、小鼠肝线粒体MDA生成的影响;(4)用分光光度法测定H2O2诱导小鼠红细胞溶血和Fe2+-VC诱导的肝线粒体肿胀程度来研究AGP的抗氧化效果;(5)小鼠随机分成对照与AGP组,腹腔注射AGP 150mg/kg•bw•d 12d后,测定小鼠血清抗活性氧能力及肝组织MDA含量。 结果: AGP具有一定的还原能力,一定浓度范围内具有显著的体外抗活性氧能力并能抑制小鼠肝组织及肝线粒体MDA的生成,可减少红细胞诱导溶血和肝线粒体肿胀程度,对小鼠体内肝组织MDA生成的抑制作用显著。 结论: AGP一定浓度范围内具有抗氧化作用。     

紫菜多酚的超声波辅助提取工艺及其抗氧化作用

研究超声波辅助提取紫菜多酚的工艺条件及其抗氧化活性。考察乙醇浓度、提取温度、提取时间、料液比对紫菜多酚提取得率的影响,并对紫菜多酚的抗氧化能力进行了测定。结果表明,超声波辅助提取最佳条件为乙醇体积分数为40%,超声波温度为35℃,超声波时间15 min,料液比为1∶125(g/m L)。多酚在0.005 mg/m L~0.5 mg/m L范围内,对DPPH·的清除率不断升高,并且能够显著抑制小鼠肝肝组织匀浆MDA的生成和抑制H2O2诱导的小鼠红细胞溶血;腹腔注射紫菜多酚对小鼠体内肝组织MDA生成的抑制作用显著高于空白组。紫菜多酚有很好的抗氧化作用。     

啤酒花超临界CO2萃余物中总黄酮的提取与抗氧化活性研究

通过单因素和正交试验确定了啤酒花CO2萃余物中总黄酮的最佳提取条件:浸提剂50%乙醇,料液比1:25(g/ml),回流提取温度70℃,提取时间2.5h,在此条件下总黄酮的提取量为68.09mg/g干酒花。抗氧化实验结果显示提取的啤酒花总黄酮对DPPH自由基的清除能力(IC505.73μg/ml)优于抗坏血酸(IC508.79μg/ml)和芦丁(IC5014.84μg/ml);啤酒花总黄酮的还原力(EC500.158mg/ml),优于芦丁(EC500.252mg/ml),弱于抗坏血酸(EC500.103mg/ml);啤酒花总黄酮对小鼠肝匀浆Fe2 H2O2诱导脂质过氧化产生丙二醛(MDA)的抑制能力(IC500.517mg/ml)优于芦丁(IC500.596mg/ml),表明啤酒花总黄酮具有显著的抗氧化活性。     

芦苇叶黄酮类提取物体内体外抗氧化性研究

研究醇提芦苇叶黄酮类提取物的体内体外抗氧化性。通过测定芦苇叶黄酮类提取物对体外大鼠肝组织匀浆、肝线粒体丙二醛（malondialdehyde,MDA）生成量及大鼠红细胞溶血的影响。结果表明：芦苇叶黄酮类提取物在0.5～10 mg/mL范围内能抑制大鼠肝组织匀浆及肝线粒体MDA的生成,抑制大鼠红细胞溶血,具有量效关系,表明芦苇叶黄酮类提取物具有体外抗氧化效果。随着剂量的增加,芦苇叶黄酮类提取物可提高S180荷瘤小鼠血清中谷胱甘肽过氧化物酶（glutathione peroxidase,GSH-Px）和超氧化物歧化酶（superoxide dismutase,SOD）活性,降低MDA含量,从而提高其体内抗氧化活性,当剂量达到300 mg/（kg·d）时,芦苇叶黄酮类提取物与10 mL/（kg·d）的氟尿嘧啶均可促进荷瘤小鼠体内抗氧化能力的提高,且二者间没有显著性差异。     

桦褐孔菌总黄酮体内外抗氧化作用

研究了桦褐孔菌总黄酮(TFIO)的体内外抗氧化功效。采用DPPH.自由基体系,脂肪氧合酶体系评价TFIO的自由基清除能力与脂肪氧合酶活力抑制作用;用分光光度法测定TFIO对H2O2诱导小鼠氧化溶血的抑制作用;并用丙二醛(MDA)及活性氧(ROS)试剂盒测定TFIO体内外作用对小鼠肝组织MDA及ROS含量的影响。体外实验发现:4.00 mg/mL TFIO对DPPH.清除率达76.77%,对脂肪氧合酶活抑制率达81.73%,对H2O2诱导的小鼠红细胞(RBC)溶血抑制率为83.33%,对小鼠体外肝匀浆MDA生成的抑制率分别为36.73%(非诱导组)、20.34%(Fe2+诱导组)与48.59%(H2O2诱导组),并使体外肝匀浆抗活性单位极显著增加至50.75 U/mL(P<0.01);体内实验表明:当腹腔注射0.5、2.0 mg/mL TFIO(0.04 mL/(g.d),11 d)后,小鼠肝组织MDA值降低达到极显著水平(P<0.01),MDA生成抑制率分别达到48.52%与58.52%。可见,TFIO在体内外均具有较强的抗氧化活性。     

黑果枸杞叶总黄酮的体外抗氧化活性研究

通过测定黑果枸杞叶总黄酮的还原能力,以及对小鼠血清羟自由基清除能力、小鼠红细胞溶血性、小鼠肝组织脂质过氧化产物MDA 生成的影响,探讨黑果枸杞总黄酮的体外抗氧化活性。结果表明：黑果枸杞总黄酮在化学本质上具有一定的抗氧化能力,能显著抑制小鼠红细胞溶血,IC50 为0.124mg/mL;能增强小鼠血清抗活性氧能力,抑制小鼠肝组织脂质过氧化产物MDA 生成,并显示出一定的量效关系。说明黑果枸杞叶总黄酮在一定浓度范围内具有抗氧化活性。     

玉米多肽对大鼠体外抗氧化作用的研究

用丙二醛(MDA)试剂盒测定MDA的含量,用分光光度法测定大鼠红细胞溶血程度.结果显示:在体外,10.00mg/ml玉米多肽使自由基诱导的大鼠肝线粒体MDA生成抑制率达39.63%,对肝组织匀浆MDA生成抑制率分别为22.83%(正常组),45.59%(Fe2 诱导组)及67.53%(H2O2诱导组).玉米多肽能抑制自由基诱导的大鼠肝线粒体肿胀,使大鼠肝线粒体肿胀度低于对照组,且剂量关系明显,表明其具有保护大鼠肝线粒体氧化损伤的作用.玉米多肽对H2O2诱导的大鼠红细胞氧化溶血有抑制作用,表明其对大鼠红细胞的氧化损伤具有保护作用.     

油菜花粉酶解物的体外抗氧化活性研究

测定了油菜花粉酶解物(CPRP)在化学模拟体系、小鼠线粒体、大鼠红细胞、小鼠肝匀浆中的抗氧化作用.结果表明,在化学模拟体系中,油菜花粉酶解物具有还原能力,可较好地清除羟基自由基.在体外试验中,油菜花粉酶解物能抑制线粒体膜的肿胀,抑制大鼠红细胞自氧化溶血和小鼠肝匀浆中丙二醛(MDA)的生成,得出了油菜花粉酶解物在生物体外有明显的抗氧化作用的结论.     

超声波辅助提取银杏叶黄酮及体外抗运动氧化作用研究

研究超声波辅助提取银杏叶黄酮及其体外抗运动氧化作用。在单因素基础上,采用正交试验优化超声波辅助提取银杏叶黄酮工艺,并分析银杏叶黄酮对小鼠肝组织丙二醛(MDA)、总抗氧化能力(T-AOC)的影响。结果表明:最佳工艺为提取功率80 W、提取时间40 min、提取温度70℃、料液比1∶25(g/m L),此条件下黄酮得率为27.32 mg/g。银杏叶黄酮能显著降低小鼠肝组织中MDA的含量(P0.05),能提高小鼠肝组织中T-AOC水平,表明银杏叶黄酮可增强机体抗氧化能力。     

菜籽多酚级分-1的体外抗氧化作用及其机制

测定了菜籽多酚级分-1在化学模拟体系、小鼠线粒体、大鼠红细胞、小鼠血清与肝匀浆的抗氧化作用。结果表明：在化学反应体系中，菜籽多酚级分-1具有还原能力，能清除活性氧，能够抑制脂肪氧合酶的活性。在体外实验中，菜籽多酚级分-1能抑制线粒体膜的肿胀，抑制大鼠红细胞自氧化溶血，增加小鼠血清抗活性氧能力，抑制小鼠肝线粒体、大鼠红细胞、小鼠肝组织匀浆MDA（丙二醛）的生成。以上实验表明：菜籽多酚级分-1在生物体内具有明显的抗氧化作用，高的还原能力与抑制生物体内氧化酶是菜籽多酚级分-1抗氧化的机制。     

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