银杏叶中黄酮类化合物的提取、纯化及测定方法的研究进展

对应用于银杏叶中黄酮类化合物的提取方法、纯化方法和测定方法的现状(主要在1999～2011年间发表的文献)及相关的原理和方法的特点作了综述。     

山丹叶中黄酮类化合物的提取及其总含量的测定

山丹为双子叶植物药百合科植物，别名山豆子花，拉丁名为原植物山丹Lilium concolor Salisb，功效为解毒消肿、活血祛瘀；主治痈疽肿毒、疔疮、吐衄、跌打损伤。     

鸡血藤中黄酮类化合物提取工艺的研究

对提取鸡血藤中黄酮类物质的工艺条件进行优选。在单因素考察的基础上,选用4个实验因素(提取温度、提取时间、料液比、乙醇体积分数)进行3水平正交试验优选,确定提取鸡血藤中总黄酮的最佳工艺参数。4种因素对鸡血藤中总黄酮提取结果的影响程度由大到小的次序为提取时间、乙醇体积分数、提取温度、料液比。总黄酮最佳工艺条件:料液比1∶30、乙醇体积分数50%、提取温度80℃、提取时间3 h,在此工艺条件下,鸡血藤中总黄酮的提取率为7.75%。该提取工艺合理,总黄酮提取率高。     

昆仑雪菊中黄酮类化合物提取与纯化

用超声法提取昆仑雪菊中黄酮类化合物,通过大孔树脂对提取液进行纯化,纯化物经聚酰胺层析柱梯度洗脱得到初步分离物,通过颜色反应和紫外光谱扫描进行定性分析。设计正交实验得到超声法提取的最佳工艺条件是65%乙醇、料液比为1∶40、超声时间60 min,此条件下提取3次,总黄酮得率可达132.6 mg/g。通过聚酰胺柱层析法分离出五个组分,初步判断它们属于不同的黄酮类物质。超声法提取总黄酮,提取率较高,聚酰胺树脂对黄酮类化合物的分离效果较好。     

银杏黄酮类化合物的提取分离

银杏叶;萃取;银杏黄酮类化合物的提取分离     

天然黄酮物质提取技术和分析方法的研究进展

综述了黄酮类化合物的提取技术及分析方法.新型提取技术如微波萃取法、超声波法、超临界萃取法、酶法、半仿生提取法;分析方法有分光光度法、高效液相色谱法、高效毛细管电泳法、薄层色谱法等.旨在为黄酮类化合物的研究、开发、应用提供参考.     

微波辅助提取刺五加中黄酮类化合物过程中的化学变化研究

利用HPLC-UV和HPLC-ESI-MSn技术系统地研究了传统中药刺五加中黄酮类化合物在微波辅助常压和高压提取过程中的化学变化, 并考察了提取压力和提取时间对其化学变化规律的影响, 结果表明, 在提取压力超过300 kPa时芦丁开始失去一个芸香糖转化为槲皮素; 随着微波照射时间的延长, 金丝桃苷、芦丁、槲皮苷和槲皮素提取产率先增加, 而后下降. 提取压力越大, 提取速率越快, 分解的速度也越快,达到最高提取产率的时间越短.     

高效液相色谱法快速测定三白草中黄酮类物质

研究了用固相萃取预分离,高效液相色谱法测定三白草中黄酮类物质。三白草中的黄酮用甲醇(90 10)加热回流提取,提取液用Waters Sep-Pak-C18固相萃取小柱预分离,以ZORBAXStable Bound(4.6 mm×50 mm,1.8μm)色谱柱为固定相,磷酸(2 998)和甲醇(以体积比50比50)为流动相,在该色谱条件下,三白草中主要的黄酮成分在1.5 min内可达到基线分离;用紫外二极管矩阵检测器检测。用该方法测定了5种三白草样品中的黄酮类物质,回收率在97%~103%之间,相对标准偏差在1.6%~2.2%之间。     

银杏叶提取物中黄酮类化合物的分光光度分析研究

建立了一种银杏叶提取物中黄酮类化合物的分光光度测定方法。研究表明在NaNO2存在下,pH在13.20～13.60范围内,银杏叶提取物与Al(NO3)3形成稳定的粉红色配合物,于λmax=510nm处进行分光光度分析。标准品选用芦丁,其标准曲线在4.606～55.27μg/mL范围内服从朗伯-比尔定律,相关系数为r=0.9998。回收率为98.58%～102.80%,RSD为0.111%。可用于银杏叶提取物中黄酮类化合物的测定。     

超声波提取川贝母黄酮类物质的工艺优化

采用超声波提取技术提取川贝母中的黄酮类物质.考察了超声功率、乙醇体积分数、料液比、超声时间和超声温度各因素对黄酮类物质提取效率的影响.在超声功率800 W条件下,通过L_9(3~4)正交试验,确定了川贝母黄酮类物质的超声波最佳提取工艺参数:超声功率为800 W,乙醇体积分数为80%,料液比为1 g∶45 mL,超声时间为2.0 h,超声温度为45℃.在最佳提取工艺条件下进行验证试验,川贝母黄酮类物质的提取率达到77.13 mg/g,RSD值为0.39%.     

Extraction and determination of hexavalent chromium in soil samples

A procedure for the extraction of Cr(VI) from solid soil-like samples was presented in which the complexing properties of diethylenetriaminepentaacetic acid (DTPA) were exploited to extract insoluble compounds of Cr(VI). A concentration of DTPA in an ammonium sulphate/ammonium hydroxide buffer equal to 0.02 mol l⁻¹ was chosen. The conditions of extraction of insoluble Cr(VI) from solid samples were optimised using soil certified reference material spiked with known concentration of insoluble Cr(VI) added as PbCrO₄. The extracts were analysed by adsorptive stripping voltammetry. Validation of the proposed procedure of extraction was carried out by analysis of certified reference material (CRM) 545 and comparison of the results obtained using the proposed and other methods of extraction in the course of analysis of natural soil samples.     

Extraction and determination of elemental selenium in sediments--a comparative study

This paper proposes a new technique to extract elemental Se from soil and sediment samples. In this study, we have identified that the purchased red elemental selenium standard (PF-Se) was impure and rather consisted of a mixture of CS₂ soluble amorphous elemental Se (ca. 10%, w/w), water soluble oxidized Se (ca. 15-17%, w/w) and, CS₂ insoluble red monoclinic elemental Se. In more recent studies, a slow oxidation and a mineral phase transition of this sample was also observed. The solubility of the amorphous elemental Se in CS₂ was at least 0.64 mg L⁻¹. The black elemental Se purchased from Sigma-Aldrich had a much lower solubility in CS₂ (7.2 μg mL⁻¹) compared to that given in the literature. Any selenium compounds with electrical charge and polar nature is insoluble in CS₂. In a sodium sulphite solution, PF-Se was completely dissolved thus giving a clear indication of the lack of selectivity in that extraction system. Other comparative studies also demonstrated that over extraction did occur with the Na₂SO₃ method. Compared to Na₂SO₃, CS₂ extraction of elemental Se is not only much simpler, straightforward and with higher analytical precision, but also much more selective and accurate. With HG-AFS, the detection limit can reach as low as 1.0 ng g⁻¹ in sediment sample owing to a low reagent blank of CS₂ solvent.     

Extraction,derivatization, and determination of metabolome in human macrophages

A GC/TOF‐MS was applied to the determination of metabolites in human macrophages. The extraction conditions and quenching conditions were investigated and optimized. The results indicated that 0.9% w/v sodium chloride at 4°C was the most favorable condition to quench macrophage, 1 mL 50% ACN for 2 min in ice bath was the optimal condition to extract 5 × 10⁶ cells. Two hundred six peaks could be detectable with peak area over 50 using this method. Among these peaks, 45 peaks with the similarity over 700 were identified using standard compounds for endogenous metabolites. Thirty‐seven out of 45 metabolites could be quantified directly by this method. Twenty metabolites were selected randomly, and 15 amino acids were used for method validation. The correlation coefficients (r) ranging from 0.9902 to 0.9977 were obtained for 15 amino acids in the range of 2.35–150.20 μg/mL. The intraday and interday precisions were lower than 19.90% for the randomly selected 20 endogenous metabolites. Using this development method and multivariate statistical technique, several potential biomarkers were found from human macrophages infected by different Mycobacterium tuberculosis (M. tuberculosis) strains. The results suggest that the method could be applied to the investigation of the pathogenicity of tuberculosis.     

Extraction and determination by liquid chromatography and spectrophotometry of naloxone in microparticles for drug-addiction treatment

This paper discusses the development and validation of two analytical methods for the assay of naloxone in microparticles, as used in the therapy of opioid drug addiction (weaning). A UV-Vis spectrophotometric method is proposed to study drug loading and drug release, due to its ease and simplicity of performance, while a high performance liquid chromatographic method is developed as a means of stability-indication. Both analytical procedures were validated according to the International Committee for Harmonization (ICH) guidelines. Although the ranges and wavelengths were different for the two analytical methods, they were both found to be specific, linear, precise, and accurate under the determined conditions.     

Extraction and spectrophotometric determination of cobalt(II) with isonitroso-5-methyl-2-hexanone

A simple and selective method is proposed for the extraction of cobalt(II) for its spectrophotometric determination using (HIMH) as an extractant. Cobalt(II) forms a yellow coloured complex with HIMH which can be extracted into chloroform. The calibration curve is rectilinear in the concentration range 0.1–5.0 μg ml⁻¹ of cobalt(II). The extracted species shows an absorption maximum at 400 nm with molar absorptivity of 1.135×10⁴ l mol⁻¹ cm⁻¹. The method has been applied for the determination of cobalt in synthetic mixtures, pharmaceutical, biological and high speed steel samples.     

悬浮液进样-火焰原子吸收光谱测定芹菜中的锌铁锰铜

不使用稳定剂,直接用蒸馏水制成芹菜样品的悬浮液,用SrCl2消除相关干扰,在磁力搅拌下进样,应用标准曲线法在同一溶液中利用空气——乙炔火焰原子吸收光谱法测定Zn、Fe、Mn、Cu等4种元素含量。结果表明,芹菜中含有丰富的Zn以及Fe、Mn、Cu。本文考察了方法的准确度和精密度。试验表明,在选定的条件下,芹菜中各元素间相互不干扰,可在同一份制备液中进行4种元素的分别测定。方法的加标回收率在90.0%~102.0%之间,相对标准偏差在0.21%~0.77%之间(n=3)。测定结果与高温灰化法一致,t检验表明两者无显著性差异。     

PEG600-Triton X-100组合表面活性剂双水相体系萃取测定类黄酮

建立了聚乙二醇(PEG)600-Triton X-100组合表面活性剂双水相体系,研究了该体系中溶液pH、缓冲体系、分相盐量及芦丁浓度等对芦丁萃取率的影响。结果表明,以(NH4)2SO4作分相盐,用量为2．5g时,在pH6.0 Britton-Robinson(B、R)缓冲体系中芦丁平均萃取率为95.2％。该体系用于萃取测定绞股蓝茶中的芦丁．结果与HPLC法测定值一致,加标平均回收率为93．5％～94．9％,相对标准偏差为0.2％～1．6％。     

Analyses of pesticides and their metabolites in foods and drinks

The importance of matrix pretreatment, sample extraction and clean-up in multiresidue methods for pesticide analyses is discussed, with emphasis on alternative new techniques attempted worldwide such as accelerated solvent extraction, microwave-assisted extraction, solid-phase extraction, solid-phase micro-extraction, matrix solid-phase dispersion, supercritical fluid chromatography, ultrasonic extraction and gel permeation chromatography. Detection employing capillary gas chromatography and high-performance liquid chromatography in conjunction with mass spectrometry, capillary electrophoresis, immunoassay techniques and others is summarized.     

苯醚甲环唑在芹菜及其土壤中的残留测定和消解动态研究

采用气相色谱-电子捕获检测, 对芹菜及其土壤中的苯醚甲环唑消解动态和最终残留量进行了研究, 评价了苯醚甲环唑在芹菜上使用后的残留行为和环境安全性. 苯醚甲环唑在芹菜及土壤中的残留消解动态均符合一级动力学方程, 苯醚甲环唑在芹菜上消解快; 苯醚甲环唑最终残留量与施药的剂量、施药次数及采样的间隔时间有关; 水解研究表明, 苯醚甲环唑是稳定的农药, 在不同温度和不同pH的研究条件下水解半衰期均大于166 d, 碱性条件更有利于苯醚甲环唑的降解.