2017/10/27 10:04
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UV1700系列紫外可见分光光度计
型号: UV-1700
产地: 江苏
品牌: 南京科捷
¥5000 - 9999
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柑橘是芸香科柑橘属植物的成熟果实,其干燥果皮是药材陈皮,具有理气健脾、燥湿化痰作用。柑橘在我国由非常丰富的资源,新鲜柑橘皮中含有丰富的黄铜类物质成分,药理学研究表明黄铜成分是极有效的活性成分,其有抗炎、抗氧化、抗过敏作用以及降低血液和肝脏中胆固醇的作用。黄酮类化合物的定量方法常用的有FPLC法和分光光度法。在实际生产和科研过程中,考虑到方法的简便、快捷及可行性,对总黄酮含量的测定,多采用NaNO₂-
AI(NO₃)₃-NaOH体系分光光度法,在510nm下测定其吸光度。由于天然植物的组成非常复杂,各种黄铜类物质性质也存在差别,并且由于黄铜类化合物提取液中各种杂质的存在,如含有的脂溶性色素和芳香油,使显色法测定总黄酮时产生混浊现象,造成很大误差。这就使分光光度法在实际测定过程中产生一些问题,影响结果的准确性。由于大多数黄酮类化合物分子中存在肉桂酰基和苯甲酰基组成的交叉共轭体系,其MeOH谱200nm-400nm的区域内存在两个主要的紫外吸收带。紫外分光光度法依据黄铜自身结构的特点,不使用显色剂,直接在其特征吸收峰处对公试样进行测定。相比较紫外分光光度法而言,510nm可见光显色法需要的试剂种类多,每一种试剂加入后需要一段反应时间,等待时间长,操作步骤繁琐。本文通过用紫外分光光度法测定各种黄酮类化合物提取液中的总黄酮含量,为提取工艺的优化提供实验依据。
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