共查询到18条相似文献,搜索用时 218 毫秒
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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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茶叶中茶多糖茶多酚茶咖啡碱的高压脉冲电场快速提取 总被引:2,自引:1,他引:2
以10倍质量的0.001MEDTA缓冲液为提取液,应用高压脉冲电场(PEF)技术成功从等外绿茶中提取功能成分茶多糖、茶多酚和咖啡碱,并与水提法的提取率进行了比较。结果表明:在缓冲液pH9.5,场强度为25kV/cm,脉冲数为10的条件下,茶多糖有最大提取率,PEF法提取率是水提法的1.91倍;在缓冲液pH9.5,脉冲电场强度为25kV/cm,脉冲数为12时,茶多酚有最大提取率,提取率是水提法的1.11倍;在缓冲液pH4.0,脉冲电场强度为25kV/cm,脉冲数为10时,咖啡碱有最大提取率,是水提法的1.05倍。 相似文献
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发芽和提取条件对玉米胚芽中超氧化物歧化酶的诱导作用 总被引:1,自引:0,他引:1
为提高玉米超氧化物歧化酶(SOD)的活力和提取率,在不同条件下对玉米进行发芽处理,从发芽玉米中剥离胚芽,并在磷酸缓冲液中浸泡,再提取SOD,并测定SOD总活力。结果表明:玉米在30℃、有光照条件下发芽4d,剥离的40g胚芽在0.05mol/L 200mL磷酸缓冲液中浸泡36h,通过胶体磨研磨浸提1h,60℃热沉淀15min,用1.5倍-20℃的丙酮沉淀SOD,经Cellulose-DE-52层析,再经SephadexG-75层析,得到的玉米SOD比活力最高,为4487.28U/mg pro,比未发芽的玉米胚芽提取的SOD的比活力(924.18U/mg pro)提高了3.86倍。 相似文献
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以酶总活力为指标对蛹虫草培养残基中的超氧化物歧化酶(SOD)提取条件进行研究,通过对培养残基与磷酸缓冲液的用量比即料液比、磷酸缓冲液pH值、提取温度、固体(NH4)2SO4饱和度这4个因素进行单因素试验与L9(34)多因素正交试验,发现料液比对SOD的提取效果影响最明显,其次为固体(NH4)2SO4饱和度和提取温度,而缓冲液pH值的影响相对较小.确定蛹虫草培养残基中SOD的最佳提取条件:料液比为1:20,提取温度为50℃,缓冲液pH值为7.6,固体(NH4)2SO4饱和度为40%,在这样的提取条件下测出的酶总活力最高,提取效果最好. 相似文献
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小麦苗中超氧化物歧化酶(SOD)提取条件的优化研究 总被引:1,自引:0,他引:1
利用磷酸盐缓冲液提取小麦苗中抗氧化组分超氧化物歧化酶(SOD),对磷酸缓冲液pH、抽提时间、热处理温度、热处理时间四个提取工艺参数进行单因素实验,并采用四因素三水平的响应曲面分析法(RSA)对上述因素的最佳水平范围进行优化,以邻苯三酚自氧化法对超氧化物歧化酶的活性进行测定。结果表明,在磷酸缓冲液pH8.0、抽提时间1h、热处理温度70℃、热处理时间15min的最优工艺条件下酶的活性较高,超氧化物歧化酶的活性可达587.60U/mL,此技术为小麦苗的综合利用提供了新方向。 相似文献
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丙酮法提取菜籽饼多酚及体外抗氧化性研究 总被引:3,自引:0,他引:3
以菜籽饼为原料,探讨了采用丙酮法提取菜籽饼多酚的工艺及丙酮多酚提取液的体外抗氧化性。以多酚得率为考察指标,选择丙酮体积分数、提取温度、料液比及提取时间进行单因素及正交试验,确定了丙酮法提取菜籽饼多酚的最优工艺条件:提取温度70℃,料液比1∶12,提取时间30 min,丙酮体积分数35%,在此条件下菜籽饼多酚得率为20.64 mg/g。以鞣酸、维生素C为对照,通过测定丙酮多酚提取液的还原能力及对DPPH.的清除能力,结果表明,丙酮多酚提取液具有一定的体外抗氧化能力。 相似文献
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Cranberry press cake, an under utilized by-product of the cranberry processing industry is a potential source of food antioxidants. The objective of this research were (1) to prepare extracts from cranberry press cake using solvent extraction (SE) and microwave assisted solvent extraction (MASE), and (2) to test the ability of these extracts to inhibit lipid oxidation in mechanically separated turkey (MST). Water, ethanol and acetone were used as extraction solvents. Heating press cake prior to extraction with 70% ethanol increased antioxidant efficacy compared to extracting unheated press cake. Water extracts were least effective in inhibiting lipid oxidation. The most effective extracts were obtained by SE with 100% acetone or MASE with 100% ethanol. A poor correlation of 0.69 was obtained between the total phenols in the extracts and their ability to inhibit thiobarbituric acid reactive substances (TBARS) formation in MST. The correlation coefficient between the amount of quercetin in the extracts and the number of days of TBARS inhibition in MST was 0.87. This indicates that although quercetin may be good inhibitor of lipid oxidation, polyphenols other than quercetin are likely have a role in the inhibition of TBARS in MST. For a similar yield of the extracts, MASE extract using 100% ethanol was a better inhibitor than 100% ethanol SE extract of lipid oxidation in MST. In terms of choice of solvent, based on their flammability and toxicity, MASE with 100% ethanol would be a more likely a choice over SE with 100% acetone, for inhibiting oxidation in MST. 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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葡萄糖异构酶细胞经丙酮处理,缓冲液抽提。DEAE—纤维素离子交挟柱层析和Sephadex G—200凝胶柱层析等方法得到分离井纯化。该法与超声破碎法相比,比活提高3.3倍,活力收率为74%,得到了高纯度异构酶,经Sephadex G—200凝胶柱层析获得较高收率的电泳纯制品。 相似文献
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Cranberries are a major source of procyanidins, an abundant class of bioactive polyphenols found in nature. The objective of this study was to apply a protocol for extraction and normal-phase high-performance liquid chromatograph-fluorescence-mass spectroscopy separation and quantification of procyanidins in cranberry extracts containing varying processing aids and/or methods of production. Cranberry extracts were best extracted using an acetone/water technique versus an acid/alkaline extraction. Procyanidins were semi-purified with C-18 and Sephadex LH-20 SPE cartridges (GE Healthcare Life Sciences, Piscataway, N.J., U.S.A.). Characterization and quantification of procyanidins up to octamers and higher molecular weight compounds, including separation of the A- and B-type dimers to tetramers was achieved. 相似文献