28 research outputs found

    Content of gentiopicroside and loganic acid in Radix gentianae and their fingerprints

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    To develop a HPLC-DAD-ESI-TOF/MS analysis method for the determination of gentiopicroside and loganic acid in Radix gentianae samples and for the research of their fingerprints.The samples were extracted using ASE for 10 min under 100 ℃ and 9.65 MPa,and divided into water phase and chloroform phase and analyzed them with HPLC-DAD-ESI-TOF/MS method respectively.Based on this method,the HPLC fingerprints of Radix gentianae were established.Comparing the spectrogram and mass spectrum of the chromatogram peak with the reference value,three compounds in water phase were identified as gentiopicroside,asafetida acid and loganic acid.There is no report of the compounds in chloroform phase.The content of gentiopicroside and loganic acid in samples of different groups were determined,separately.The fingerprints were compared by the software of the similarity evaluation system for chromatographic fingerprint.The water phase fingerprint congruence coefficients of samples from six different areas were above 0.90,however,the chloroform phase fingerprint congruence coefficients were within 0.62-0.99.This method can be used for determination of potent component in Radix gentianae and its quality control.Radix gentianae from different producing areas have the largest diversities,and the diversities embodied in the content of chloroform phase compounds.青岛“2004将才计划”(04-3-JJ-11);; 国家海洋局青年基金资助项目(2005602);; 崂山区政府区校共建生物医药研发测试中心资助(LS-05-KJZX-76)

    Determination of Gentiopicroside and Loganic Acid in Radix Gentianae by MEKC and MEEKC Mode

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    目的建立胶束电动毛细管色谱(MEKC)和微乳液毛细管电动色谱(MEEKC)分析龙胆药材中龙胆苦苷和马钱子苷酸含量的方法。方法采用加速溶剂萃取法(ASE)对龙胆药材进行提取,萃取温度:100℃,压力:9.65MPa,萃取时间:10min。采用未涂层熔融石英毛细管(内径75μm,有效长度50cm)。分别考察了两种分离模式下电泳介质的构成和电泳过程中的各操作参数对样品分离过程的影响,优化了MEKC和MEEKC的分析条件,在各自对应的缓冲液体系下,MEKC和MEEKC分离电压分别为30和22kV,柱温均为25℃,检测波长均为238nm。结果在选定的工作条件下,龙胆苦苷和马钱子苷酸与其他组分达到了基线分离,两种成分的浓度与其响应信号值之间具有较好的线性相关性,加标回收率在96.3%~105.1%之间,检测限均低于10mg·L-1,对6处不同产地的龙胆药材进行了分析,并对测定结果进行了t检验,结果表明,两种模式下,测定结果之间不存在显著性差异,而不同产地的龙胆药材的龙胆苦苷和马钱子苷酸含量之间存在较大差异。结论本方法简便,准确,快速,重现性较好,可用于龙胆药材有效成分的含量测定和质量控制。OBJECTIVE To develop MEKC and MEEKC modes for the determination of gentiopicroside and loganic acid in extracts of Radix Gentianae. METHODS The analyte was extracted from Radix Gentianae samples by accelerated solvent extraction, and the extraction conditions were optimized. Separation and determination were carried out on a bared fused silica capillary(50 cm×75 μm) with corresponding buffer. The run voltage of MEKC and MEEKC were 30kV and 22 kV respectively. Detection wavelength of DAD was at 238 nm and column temperature was 25 ℃. RESULTS The developed ASE-HPCE method was simple and reliable for the determination of gentiopicroside and loganic acid in Radix Gentianae samples with a broad linear dynamic range, a recovery range of 96.3%~105.16%,and the detection limit was below 10 mg·L-1. The contents of gentiopicroside and loganic acid in six samples from different regions were determined by the developed method in two modes. T-test value indicated that the determined contents of gentiopicroside and loganic acid by MEKC and MEEKC were consistent. CONCLUSION The method is simple,accurate,rapid and with good reproducibility.It can be used to determine active components in Radix Gentianae.国家自然科学基金重点项目(20235020);; 青岛“2004将才计划”(04-3-JJ-11);; 崂山区校区共建生物医药研发测试中心资助(LS-05-KJZX-76

    大孔吸附树脂分离纯化龙胆药材中龙胆苦苷和马钱子苷酸的研究

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    目的:建立利用大孔吸附树脂对龙胆药材中龙胆苦苷和马钱子苷酸进行富集和分离纯化的方法。方法:采用加速溶剂萃取法对龙胆药材中两种有效成分进行高效提取,比较了D301,AB-8,D101,XDA-1四种大孔树脂对龙胆苦苷和马钱子苷酸的吸附性能,最终确定采用D301型大孔对脂对二者进行富集吸附,对其工艺参数进行优化,全程采用高效液相色谱进行目标化合物浓度检测。结果:化优后的工艺参数为:上样浓度:0.2 g/mL,最大上样量:0.25 g龙胆药材/g树脂,最佳静态吸附时间:8 h,采用8%和55%的乙醇溶液对龙胆苦苷和马钱子苷酸分别进行洗脱;龙胆苦苷和马钱子苷酸分别富集在8%和55%的乙醇洗脱液中,洗脱液浓缩后冷冻干燥,可得到纯度分别为74.3%和80.9%的粗产物,龙胆苦苷和马钱子苷酸的回收率分别为70.11%和67.82%。结论:此法效率较高,操作简便,即可用于实验室制备少量的难以购置的标准品,也可进行放大研究,用于工业生产。国家自然科学基金重点项目(20235020);; 青岛“2004将才计划”(04-3-JJ-11);; 共建生物医药研发测试中心(LS-05-KJZX-76)资

    贵州高原山区正负地形特征及其对人口分布的影响

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    正负地形可通过源汇过程对水、土资源进行再分配,影响着山区的人口分布,有待深入研究。获取正负地形数据,运用6个指标和多元逐步回归方法,分析贵州高原山区正负地形特征及其对人口分布的影响。研究表明:①贵州高原山区的正负地形结构异质性明显。蚕食度、深切度、平均粗糙度比、形状指标、匀度指数、破碎度的平均值分别为1.07、371m、 1.01、3.40、325和3.34。表明正地形被负地形蚕食明显、切入深度大,正、负地形的粗糙度基本相当,正负地形景观斑块呈现形状不规则、面积不均匀的破碎状态。6个正负地形指标中,匀度指数的变异性最大,变异系数为90.43%;平均粗糙度比的变异性最小,变异系数为1.06%。②贵州高原山区的人口分布不均匀性突出。人口累积达到40%时,累积面积百分比为14%;人口累积达到80%时,累积面积百分比约为50%;余下50%的面积则只积累了约20%的人口。③6个正负地形指标中,蚕食度和深切度是影响人口分布的主要因素。蚕食度通过影响土地承载力决定了人口的集聚水平,与人口密度呈正相关关系。深切度通过影响人居环境的地质灾害风险决定了人口的集聚水平,与人口密度呈负相关关系。研究成果为研究地形条件的人口影响提供补充,并为贵州高原山区人-地关系协调和土地可持续管理提供参考。国家自然科学基金(41761003,41867001,41661081)教育部人文社会科学研究项目(18YJC850010)贵州省普通高等学校科技拔尖人才支持计划(黔教合KY字[2018]042

    基因编辑技术在莱茵衣藻中的应用进展

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    基因编辑技术已经成为功能基因组学和作物分子育种精准且有力的工具。莱茵衣藻(Chlamydomonas reinhardtii,简称衣藻)是光合作用、黑暗异养代谢、厌氧代谢和生物制氢、营养和能量代谢等研究领域的重要模式生物。近20年来,基因编辑技术,如锌指核酸酶(ZFNs)、转录激活物样效应物核酸酶(TALENs)、CRISPR/Cas9和CRISPR/Cpf1等的发展,更加推动了以衣藻为模式生物的研究。现对衣藻中的核基因组靶向基因编辑技术的应用及最新研究进展等进行总结,以期为衣藻相关领域的研究提供参考

    High Throughput Preparation of Magnesium Hydroxide Flame Retardant via Microreaction Technology

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    High Throughput Preparation of Magnesium Hydroxide Flame Retardant via Microreaction Technolog

    四点接触球轴承内外圈沟道圆度误差对旋转精度的影响

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    以四点接触球轴承为研究对象,针对四点接触球轴承旋转精度开展研究,提出了同时考虑轴承内圈和外圈圆度误差的轴承旋转精度数值计算方法。以轴承径向跳动量描述轴承的旋转精度,根据四点接触球轴承的结构特点及运动关系,构建了轴承径向跳动的数学模型,并基于Matlab编写程序进行仿真计算。结果表明,内圈沟道谐波阶次不变时,轴承的旋转精度会随着谐波幅值的增大而降低;当内圈谐波阶次为3即内圈沟道廓形为三棱圆时,轴承径向跳动最小,轴承旋转精度最高;当外圈圆度误差谐波次数与钢球的个数存在整倍关系时,外圈的径向跳动最大,当外圈圆度误差谐波次数是钢球个数一半的奇数倍时,外圈径向跳动的值最小

    The egg types of Calanus sinicus in Xiamen Harbor of China

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    【中文摘要】 对厦门港中华哲水蚤(Calanus sinicus)的卵型进行观察和研究,获得主要结果如下:(1)厦门港中华哲水蚤仅存在一种基本卵型,属于无鞘卵,但卵表面具有透明、柔软的胞膜(blister),胞膜呈褶皱结构;(2)胞膜可因外力而脱落,但胚胎仍可以正常发育;(3)在实验室水温为16~22℃条件下,受精卵均可正常孵化与发育;(4)胞膜的厚度有一定的变化,它随着水温的升高有减小的趋势.卵型分析与孵化实验均证实:厦门港中华哲水蚤不存在休眠卵(dormant egg)或滞育卵(diapause egg). 【英文摘要】 Calanus sinicus,an independent species divided from C.pacificus,dominated in all main seas of China,plays the same role in China neritic ecosystem as C.finmarchicus in Atlantic.As a mega-copepod, C.sinicus has been widely studied because of its connecting link between the preceding and the following in marine food webs.In Xiamen Harbor,located opposite of Taiwan Island,C.sinicus usually appears in the late autumn or early winter and disappears at the beginning of summer.Then how can they spend the summer? D...国家重点基础研究发展规划(973)项目资助(G1999043708
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