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甘草是我国传统的中药,来源于豆科植物甘草(Glycyrrhiza uralensis Fisch)、胀果甘草(G.inflata Bat.)或光果甘草(G.glabra L.)的干燥根和根茎[1]。具有多种药用功效,主要生长在我国西北、华北、东北等三北地区[1]。近年来在内蒙古自治区西部人工栽培甘草已获成功,甘草资源极为丰富[2]。甘草酸(glycyrrhizic acid,GA)又名甘草甜素,是甘草中分离出的一种三萜类化合物[3],也是最重要的有效成分之一。本文对甘草中甘草酸及其他成分的提取分离方法进行了摸索和改进,取得了较好的效果。 相似文献
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溶剂萃取技术是一种很有发展前景的油砂分离方法,具有操作节水节能、适用性广、分离效率高、无乳化现象、溶剂可循环利用、污染小等优点。本研究细致的考察了溶剂种类、溶剂用量、溶剂极性、操作条件(如温度、搅拌强度及时间等)对油砂沥青萃取率的影响,并通过正交实验获得了最佳萃取条件。在此基础上,对萃取组分和残留物质进行族组分分析,发现沥青中的沥青质的溶解性对温度的敏感性大于其余3种组分(饱和分、芳香分和胶质)。同时,通过实验还观察到萃取过程中悬浮于溶液中的沥青颗粒主要以沥青质组分为主,并含有一定量的轻组分;而油砂中的黏土等细颗粒固体(<44μm)则与悬浮沥青颗粒共存于溶液中,有必要采取过滤、离心等手段对萃取液进行处理,以防这些颗粒对后续的炼油过程产生危害。根据前述的实验研究结果,提出了油砂溶剂萃取过程的机理模型。 相似文献
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本文研究了从甘草中提取黄酮类化合物的方法和路线,并利用聚酰胺色谱法对其进行分离。结果表明,用超声提取法,以80%的乙醇作溶剂,最佳提取条件为:功率1000w、温度45℃,固液比为1:10,超声时间60min(20,20,20);聚酰胺色谱分离时,以正丁醇:乙醇:水(1:4:5)或丙酮:水(1:1)为洗脱剂时的分离效果较好。 相似文献
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《精细化工》2017,(11)
以十八烷基硅烷键合硅胶(ODS)为固定相,V(乙醇)∶V(水)=30∶70为流动相的模拟移动床色谱(SMBC)体系对甘草黄酮中甘草苷与甘草素进行连续分离。SMBC体系设置洗脱带Ⅰ:1根色谱柱;精制带Ⅱ:2根色谱柱;吸附带Ⅲ:2根色谱柱,Ⅰ带独立,Ⅰ带洗脱液为乙醇。按照理想三角形理论选择SMBC操作参数,操作参数包括流动相流速、进料液流速和切换时间。结果表明:接近三角形底边选择SMBC的操作条件,在萃余液出口得到甘草苷,HPLC纯度高于70.44%,收率高于95.17%,同时在萃取液出口得到甘草素,HPLC纯度高于73.10%,收率高于90.74%,SMBC能有效分离甘草苷和甘草素。甘草苷萃余液和甘草素萃取液分别经浓缩、重结晶后,两种产品HPLC纯度均超过96%。 相似文献
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Minglei Tian Hongyuan Yan Kyung Ho Row 《International journal of molecular sciences》2008,9(4):571-577
The extraction and separation conditions of glycyrrhizic acid and glabridin from licorice were investigated. By changing the different extraction solvents, procedures, times and temperature, the optimum extraction condition was established: the used of ethanol/water (30:70, v/v) as an extraction solvent, and 60 min dipping time under 50°C. The extracts of licorice were separated and determined by reversed-phase high performance liquid chromatography with a methanol/water (70:30, v/v, containing 1% acetic acid) as the mobile phase. Under the optimum extraction condition, 2.39 mg/g of glycyrrhizic acid and 0.92 mg/g of glabridin were extracted from Chinese licorice and the recoveries were 89.7% and 72.5% respectively. 相似文献
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《分离科学与技术》2012,47(9):1406-1413
The aim of this work was to study the separation of liquiritin (LQ) from glycyrrhizic acid (GA), in licorice aqueous solutions using nanofiltration (NRT-7450) membrane. The LQ and GA components are the main active ingredients of licorice root extract with various pharmacological effects, The effects of transmembrane pressure, feed temperature, feed pH, and cross-flow velocity on permeate flux and recovery were determined. A lab scale cross-flow set up using flat-sheet configuration membrane was employed for all experiments. SEM micrographs showed the changes in the fouled surface during operating time. The applied transmembrane pressure, feed temperature, feed pH, and cross-flow velocity were varied from 4 to 10 bars, 30 to 40°C, 3 to 9, and 0.8 to 3.1 m s?1 respectively. The obtained recoveries for GA and LQ varied between 0.65 to 1.86% and 16.89 to 41.65%, respectively. The optimum operating conditions for separation LQ from GA in licorice aqueous solutions using NRT-7450 nanofiltration membrane were 1.8 m s?1cross-flow velocity, 8 bars transmembrane pressure, 40°C of feed temperature and pH 7. 相似文献
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Pre-dispersed solvent extraction (PDSE) was used to extract quercentin from its diluted solution. The influences of temperature, phase volume ratio (PVR), concentration of sodium Dodecyl benzene sulphonate and pH value etc. on the extraction efficiency were examined. It is found that, compared with traditional extraction techniques under the same condition, a higher extraction productivity can be obtained by PDSE. The stability of colloidal liquid aphrons plays an important role in this process. In a certain scope, the extraction efficiency increases with PVR. Excessive amount of solvent is not much helpful. A new analytical method by using ultraviolet spectrometer to determine the concentration of quercentin is established. 相似文献
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Pre-dispersed solvent extraction (PDSE) was used to extract quercentin from its diluted solution. The influences of temperature, phase volume ratio (PVR), concentration of sodium Dodecyl benzene sulphonate and pH value etc. on the extraction efficiency were examined. It is found that, compared with traditional extraction techniques under the same condition, a higher extraction productivity can be obtained by PDSE. The stability of colloidal liquid aphrons plays an important role in this process. In a certain scope, the extraction efficiency increases with PVR. Excessive amount of solvent is not much helpful. A new analytical method by using ultraviolet spectrometer to determine the concentration of quercentin is established. 相似文献
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《分离科学与技术》2012,47(8):1104-1111
This study investigated a novel, simple, and economical method for the preparation and purification of glabridin from licorice roots. Glabridin was initially obtained from ethyl acetate extraction of licorice, followed by using solid phase extraction (SPE) and preparative high performance liquid chromatography (HPLC). The content of glabridin increased from 0.23% to 35.2% after SPE, and then a 16 mg product at a high purity of over 95% was obtained from 10 g licorice roots after purification by preparative HPLC. The purity was assessed by analytical HPLC, and the purified compound was characterized by LC-MS/MS and 1H NMR. 相似文献
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溶剂萃取法分离氢化可的松和表氢化可的松 总被引:2,自引:0,他引:2
针对工业上现有结晶分离工艺的缺点,提出了分离氢化可的松及其光学异构体表氢化可的松的新方法——溶剂萃取法。实验发现,在常规醇类、酮类、酯类、醚类、氯代烃类和芳香烃等溶剂中,乙酸丁酯具有较好的萃取分离性能,以乙酸丁酯为萃取剂用溶剂萃取法分离氢化可的松粗品可获得纯度为98%以上的氢化可的松,已达到工业生产水平。文中还研究了乙醇含量、温度、盐析效应和pH对分配的影响。 相似文献
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《分离科学与技术》2012,47(14):3259-3270
Abstract An attempt has been made to extract glycyrrhizic acid (GA) from licorice root by surfactant mediated cloud point extraction (CPE) using non‐ionic surfactant (Triton X‐100). Almost all of the GA molecules were concentrated in the surfactant‐rich phase (also called coacervate phase) after phase separation. The pH is the most critical factor regulating the distribution of GA in the micelle which related to the ionization form. The other effects of the concentration of GA and the surfactant, the temperature, and the salt concentration on the extraction efficiency of GA in the coacervate phase and aqueous phase have been studied. The mechanism of CPE of GA was explored with transmitting electron microscopy. It was deduced that aggregate GA molecules were adsorbed on micelles' outer poler mantle and inner cross‐linked micelles at high GA concentrations in coacervate phase. 相似文献