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优化了甲醇-水流动相HPLC测定银杏萜内酯的方法,建立了线性回归方程,并与药典正丙醇-四氢呋喃-水流动相方法进行比较。在此基础上,用两种方法对银杏叶、银杏外种皮、白果以及银杏叶提取物(EGB)样品中的萜内酯含量进行了对照分析。结果表明,甲醇-水梯度洗脱基线噪音小,柱效高,分离时间短。优化的洗脱条件为:甲醇-水为流动相,0~2 min,0~20%甲醇; 2~32 min,20%~60%甲醇,建立的方法在50~2 000 mg/L的浓度范围内具有良好的线性关系,检出限为0. 05~0. 09μg,不同浓度水平的加标回收率为92. 4%~101. 6%,相对标准偏差(RSD)值为2. 7%~5. 1%。两种方法测定银杏萜内酯没有明显差别,其中测定银杏叶中白果内酯、银杏内酯C、银杏内酯A、银杏内酯B的相对误差分别为0. 86、4. 2、1. 7、3. 9。 相似文献
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硫酸肼被广泛应用于各行各业,并且用量逐年递增。电感耦合等离子体发射光谱(ICP-OES)法分析元素含量具有精度高、效率高、覆盖面广等优点。从硫酸肼中铁、铜、铅的检测要求入手,确定ICP-OES法检测硫酸肼中铁、铜、铅的谱线选择、加标或工作曲线方法选择等条件。采用该方法,铁元素质量浓度在5 mg/L以内,铜、铅元素质量浓度在2 mg/L以内,质量浓度与光谱强度线性关系良好,线性相关系数均在0.999 0以上;方法的精密度为3.39%~10.58%,加标回收率为86.5%~99.7%。该法分析结果准确度高、稳定性好,能满足国内外对硫酸肼中铁、铜、铅的检测要求。 相似文献
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用异丙醇作溶剂溶解双硫腙,Tween-20作为增溶剂,在盐酸介质中,双硫腙水相直接光度法测定水中痕量铅。铅与双硫腙配合物的最大吸收波长为480nm,铅离子在0~150μg/L浓度范围内呈线性,相关系数r=0.9962,回收率为99.4%~101.4%。 相似文献
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可溶有机试剂对ICP-AES测定水质铅的影响 总被引:1,自引:0,他引:1
通过三种有机试剂对铅浓度变化结果的对比,得到含2%丙酮的溶液试剂用量及仪器检测性能条件最佳。并对相关参数验证,确证方法标准曲线线性良好,灵敏度增加;计算得到的检出限0.007 mg/L低于现行标准;精密度1%~12%;准确度90%~105%,符合检测要求。为准确、有效检测微量含铅水质提供新方法。 相似文献
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银杏叶黄酮类化合物提取方法的研究 总被引:4,自引:0,他引:4
对纤维素酶预处理和甲基化β-环糊精溶液相结合提取银杏叶总黄酮的工艺进行了探讨,考察了料液比、酶浓度、温度、时间及pH值对酶解效果的影响,以及M-β-环糊精浓度、温度和时间对浸提效果的影响。得到最佳酶解预处理条件为:经料液比(银杏叶质量与纤维素酶溶液体积之比)1/60、酶质量浓度0.2mg/mL、酶解温度40℃、酶解介质pH=6.5、酶解时间150min处理后,在M—β-环糊精质量分数2.0%、温度60℃条件下浸提180min,总黄酮得率可达2.68%。该工艺为银杏叶黄酮类化合物提取提供了新途径,同时避免了有机溶剂的使用,便于纯化,值得推广。 相似文献
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目的 对银杏黄酮的提取工艺进行优化,并对其清除自由基活性进行研究;方法 通过响应面法优化乙醇浓度、提取温度、超声时间、液固比对产率的影响,体外清除自由基对抗氧化性进行研究;结果 当乙醇浓度为75%、超声时间控制为2 h、提取温度为80 ℃、液固比为30时,提取产率最高为2.82%,抗自由基结果表明,反应时间10 min清除率趋于稳定,银杏黄酮加入量1.00 mL,抗自由基活性高达68.9%; 结论 银杏黄酮具有较强的抗自由基活性,可以作为食品药品或者美容产品的添加剂. 相似文献
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酶解-溶剂提取银杏叶活性成分工艺条件 总被引:5,自引:0,他引:5
研究了酶法与溶剂提取相结合提取银杏叶中活性成分银杏黄酮的工艺条件。通过正交试验找出纤维素酶法及溶剂提取的最佳工艺条件,通过紫外分光光度检测及紫外扫描进行产物分析。纤维素酶的最佳提取工艺条件为纤维素酶浓度40 U/mL,酶解pH值4.8,酶解温度55℃,酶解时间90 m in。溶剂提取的最优工艺条件为无水乙醇∶粗提液(体积比)=1∶10,石油醚∶粗提液(体积比)=3∶1,乙酸乙酯∶粗提液(体积比)=2∶1。酶解-溶剂提取是一种安全高效的提取方法。 相似文献
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银杏内酯的提取纯化与分离 总被引:2,自引:0,他引:2
以银杏叶标准化提取物为原料 ,经乙酸乙酯提取纯化得高纯度的银杏内酯混合物 ,方法简单 ,银杏内酯含量达 95 1% ;再以其混合物经硅胶柱层析 ,得到银杏内酯A、银杏内酯B及银杏内酯C的单体化合物 相似文献
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X Yao E Shang G Zhou Y Tang S Guo S Su C Jin D Qian Y Qin JA Duan 《International journal of molecular sciences》2012,13(8):10305-10315
The extract from Ginkgo biloba leaves has become a very popular plant medicine and herbal supplement for its potential benefit in alleviating symptoms associated with peripheral vascular disease, dementia, asthma and tinnitus. Most research on G. biloba leaves focus on the leaves collected in July and August from four to seven year-old trees, however a large number of leaves from fruit cultivars (trees older than 10 years) are ignored and become obsolete after fruit harvest season (November). In this paper, we expand the tree age range (from one to 300 years) and first comparatively analyze the total flavonol glycosides and terpene lactones at different ages, from different cultivation sources and genders of G. biloba leaves collected in November by using the validated HPLC-ELSD and HPLC-PDA methods. The results show that the contents of total terpene lactones and flavonol glycosides in the leaves of young ginkgo trees are higher than those in old trees, and they are higher in male trees than in female trees. Geographical factors appear to have a significant influence on the contents as well. These results will provide a good basis for the comprehensive utilization of G. biloba leaves, especially the leaves from fruit cultivars. 相似文献
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综述了我国银杏叶提取物加工之现状,提出了保证产品质量,降低生产成本的根本办法在于选择优质原料和采用先进生产工艺。作者通过实验证明,选用黄酮苷含量≥1.20%,萜内酯含量≥0.30%的优质银杏叶作原料,采用先进工艺,每kg银杏叶提取物的生产成本可降至1000元以下。 相似文献
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Green synthesis of nitrogen-doped carbon dots from ginkgo fruits and the application in cell imaging
In the report, microwave-assisted and hydrothermal methods were adopted respectively to produce nitrogen doped carbon dots (N-CDs) using ginkgo fruits as the sole carbon source without additional surface passivation agents. The differences between these two N-CDs were compared in luminescence properties, particle sizes and morphologies. The TEM images showed that both microwave-assisted N-CDs (M-N-CDs) and hydrothermal N-CDs (H-N-CDs) were well dispersed, and the morphology of H-N-CDs was more uniform. The fluorescence results indicated the H-N-CDs possessed better fluorescence emission characteristic. Thus, the H-N-CDs with better luminescence properties were characterized by FT-IR, XPS, fluorescence and UV–Vis spectroscopy. Also, the stability and cytotoxicity of H-N-CDs synthesized by ginkgo fruits as the fluorescent probes were studied. Eventually, the H-N-CDs were applied in cell imaging using HeLa cells and KYSE410 cells as the cell models. 相似文献