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研究猪肝SOD的分离提取、纯化以及初步表征。以猪肝为原料,通过抽提液加热、丙酮沉淀和Sephadex G-200层析柱色谱提取、纯化Cu,Zn-SOD;在单因素试验的基础上,采用L(934)设计对提取工艺进行系统优化。结果表明:经过热变性,可以除去大部分杂蛋白,提高了SOD的比活力;最佳的提取条件是:在1.4%的盐浓度下,于70℃水浴中热变性10 min,然后加1.6倍体积的丙酮获得SOD粗沉淀;溶解后的粗酶液经Sephadex G-200层析柱纯化后,经SDS-PAGE电泳检测为单一条带,HPLC检测显示为单一对称峰,均表明最终得到了高纯度的SOD;紫外-可见吸收光谱和ICP-MS分析结果均表明得到的是含铜、锌的SOD,即Cu,Zn-SOD;以邻苯三酚为底物,该酶的Km值为1.574,Vmax为0.268。 相似文献
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在单因素试验基础上,结合Plackett-Burman、Box-Behnken设计及响应面分析法进行回归分析以确定海洋胶红酵母菌Rhodotorula sp. CD-008产超氧化物歧化酶最佳发酵条件,并通过盐析、超滤离心、Sephadex G-100凝胶过滤层析研究了酶的分离纯化条件。结果表明,pH、转速、温度对酶活力有显著影响,最优发酵条件为pH 5.34、转速150 r/min、温度21.40 ℃,优化后发酵液酶活力达到6 430.52 U/g湿菌体,比优化前提高了1.53倍。粗酶液经65%饱和度的硫酸铵盐析、超滤离心、Sephadex G-100凝胶过滤层析后获得的SOD比酶活达到419.90 U/mg,纯化倍数为9.60倍,蛋白回收率为8.2%。SDS-PAGE凝胶电泳显示,纯化后的SOD的分子质量约为37.5 ku。 相似文献
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以植物新品种黄棒菜为原料,研究料液比,浸提温度及pH,热变性温度及时间、丙酮加入量等因素对黄棒菜超氧化物歧化酶(SOD)提取效果的影响,利用正交试验与单因素试验优化提取工艺。结果表明,提取SOD的最佳条件为:料液比1︰3(g/mL),浸提温度0℃,pH 7.0,50℃热变性20 min,1.5倍酶液体积的丙酮,此时SOD纯化倍数可达3.17。经层析纯化及真空冷冻干燥,获得SOD成品。最佳条件下处理新鲜黄棒菜叶茎、叶片组织,测得SOD最终比活力分别为7662.23 U/mg,4897.39 U/mg,纯化倍数达17.55、23.08,叶茎更适于提取SOD。经电泳检测,黄棒菜SOD相对分子质量约80 kDa,据文献鉴定为Mn-SOD。试验结果为黄棒菜SOD的分离纯化及资源开发提供技术参考。 相似文献
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采用热变性法、磷酸缓冲液提取法、热变性法+磷酸缓冲液提取法、氯仿-乙醇沉淀法、丙酮沉淀法5种方法对大蒜细胞溶质中超氧化物歧化酶(SOD)进行了粗提、分离纯化.实验结果表明热变性法+磷酸缓冲液混合法所得的SOD的粗提物活性较高;丙酮沉淀法是SOD纯化的最好方法;不同的丙酮加入量与搅拌时间会影响SOD的纯化结果,其最佳条件是加入0.6倍体积的丙酮,搅拌15 min.在此优化条件的基础上,研究不同生长阶段大蒜SOD酶活力,大蒜中SOD酶活力随生长过程,总体成上升趋势.在第五周以后趋于稳定,SOD酶活力达到最高1.210. 相似文献
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目的:探讨大麦虫超氧化物歧化酶(SOD)分离纯化条件及其性质,为大麦虫利用提供科学依据。方法:以大麦虫为原料,经盐析沉淀、DEAE-Sepharose FF阴离子交换柱层析和Sephadex G-75凝胶过滤层析等纯化, 变性聚丙烯酰胺凝胶电泳(SDS-PAGE)方法对蛋白质的组分进行分离并确定其分子质量,原子吸收光谱仪鉴定酶的类型。结果:获得了一种酶比活力较高的大麦虫SOD,酶的纯化倍数为68.54倍,分子质量为37.30kD,属于含铜锌超氧化物歧化酶(Cu,Zn-SOD),且在278nm波长处有紫外吸收峰,稳定性较好,最适温度为40℃,最适pH值为6.0,对H2O2、β-巯基乙醇试剂十分敏感,受氯仿-乙醇混合液(3:5,V/V)的影响较小。结论:大麦虫SOD具有较高的酶比活力,稳定性好,具有较高的利用价值。 相似文献
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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. 相似文献
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Sophie Guillot Laurence Peytavi Sylvie Bureau Renaud Boulanger Jean-Paul Lepoutre Jean Crouzet Sabine Schorr-Galindo 《Food chemistry》2006
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. 相似文献
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Jesus Simal-Gandara Miguel Sarria-Vidal Arjen Koorevaar Rinus Rijk 《Food Additives & Contaminants》2000,17(8):703-711
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. 相似文献
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M. S. Garcí a-Falc n J. Simal-G ndara S. T. Carril-Gonz lez-Barros 《Food Additives & Contaminants》2000,17(12):957-964
A simple, rapid and inexpensive method has been developed for the determination of benzo[a 相似文献
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H. J. Van Den Top A. Boenke P. A. Burdaspal J. Bustos H. P. Van Egmond T. Legarda A. Mesego A. Mourino W. E. Paulsch C. Salgado 《Food Additives & Contaminants》2001,18(9):810-824
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. 相似文献
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《肉类研究》2014,(2)
<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 相似文献
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《印刷工业》2014,(11):95-95
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%. 相似文献
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《印刷工业》2014,(8):103-103
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 相似文献
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《印刷工业》2014,(12):102-103
Sponsored by Printing and Printing Equipment Industries Association of China (PEIAC) and organized by Print China magazine, the Seventeenth Beijing International Printing Information Conference (INFOPRINT 2014) was successfully held on 11th Dec. 2014 at Dongguan Exhibition International Hotel. 相似文献