新型含吡啶基树脂对甜菊糖中莱鲍迪甙A的富集与分离

研究了含吡啶功能基大孔吸附树脂对甜菊糖的吸附量与吸附选择性作用 .分析了树脂极性及不同骨架结构对吸附选择性的影响 .并分别通过甲醇或乙醇的选择性洗脱及树脂动态吸附分离两种方法研究树脂对甜菊糖中莱鲍迪甙A的富集作用 .结果表明 ,树脂动态分离法可以有效地从高甜菊甙甜菊糖中分离富集出高莱鲍迪甙A产品 ,该方法具有一定的工业应用前景 .     

几种树脂对西红花糖苷的吸附性能的研究

本文系统研究了硅胶和几种国产吸附树脂对西红花提取物溶液的吸附与洗脱性能，包括树脂的筛选，洗脱剂的选择，并研究了pH，温度和西红花提取物的浓度对西红花提取在SZ－1吸附树脂上的吸附影响，结果表明，SZ－1吸附树脂对西红花提取物的吸附能力较强，洗脱能力为最好，其吸附性能和洗脱性能均优于常用色谱固定相硅胶，SZ－1吸附树脂的静态吸附容量为1．04g/g，动态吸附容量为0．5－0．6g/g，洗脱率可达98％以上，且吸附速度快，易于洗脱和再生。     

含酮基吸附剂对莱鲍迪甙A的吸附选择性研究

合成了一系列具有不同骨架结构的中极性含酮基大孔吸附树脂，研究了树脂极性与骨架结构的关系，讨论了树脂对甜菊糖中两种主要糖甙甜菊甙及莱鲍迪甙Ａ的吸附能力和吸附选择性，并设计通过树脂柱的动态色层法从甜菊甙含量高的甜菊糖中成功地分离出高莱鲍迪甙Ａ糖产品．     

大孔吸附树脂对氢化可的松的吸附与洗脱性能研究

本文系统研究了大孔附树脂对水溶液中氢化可的松的吸附与洗脱性能,包括树脂的筛选,氢化可的松的渡,解吸剂的选择。结果表明,用AB-8树脂比其它的树脂有更优的性能,其静态吸附容量比试剂级微球硅胶大一个数量级以上,且吸附速度快,易于洗脱再生,是一种具体工业化应用前景的优良吸附剂。     

酚醛型吸附树脂对咖啡因和茶碱吸附性能的研究

用静态和动态方法研究了酚醛型吸附树脂JDW-2和DuoliteS-761对咖啡因和茶碱的吸附行为.结果表明,自制树脂JDW-2对咖啡因和茶碱的吸附性能明显优于DuoliteS-761.树脂的比表面积、含水量、酚羟基的含量与吸附关系密切,尽管JDW-2的比表面积比DuoliteS-761小,但前者比后者具有更高的含水量(42%)和酚羟基含量(3.72mmol/g).在静态条件下,JDW-2吸附咖啡因的速率比DuoliteS-761快,JDW-2树脂对咖啡因和茶碱饱和吸附量分别为246和127mg/g干树脂,而DuoliteS-761树脂对它们的吸附量分别为121和53mg/g干树脂;JDW-2和DuoliteS-761吸附咖啡因的初始阶段是粒扩散控制过程;酚醛型吸附树脂等温吸附咖啡因和茶碱的平衡吸附数据符合Langmuir方程.酚醛型吸附树脂吸附咖啡因和茶碱属单分子层吸附.在动态条件下,1mol/LHCl和40%甲醇溶液以1.5BV/h来洗脱吸附咖啡因的JDW-2,在4～5个床体积的洗脱率分别是88%和93%,而1mol/LHCl和80%甲醇溶液以1.5BV/h来洗脱吸附茶碱的JDW-2,在3～4个床体积的洗脱率分别是91%和96%,表明酚醛型吸附树脂具有良好的洗脱性能,用1mol/LHCl和40%(或80%)甲醇溶液作复合洗脱剂从JDW-2中洗脱咖啡因(或茶碱),效     

酚醛型吸附树脂对水体系中吡啶和N,N-二甲基苯胺的吸附性能研究

研究了酚醛型吸附树脂在水体系中对吡啶和N，N-二甲基苯胺的静态和动态吸附行为．结果表明，在水中树脂对吡啶和N，N-二甲基苯胺的吸附主要以疏水吸附机理进行；吸附吡啶和N．N-二甲基苯胺的初始阶段，即达到38．3～48．9％平衡吸附时，吸附速率数据和半经验速率方程很吻合：酚醛型吸附树脂等温吸附吡啶和N，N-二甲基苯胺的平衡吸附数据符合Langmuir方程，相关系数在0．99以上，酚醛型吸附树脂吸附吡啶和N，N-二甲基苯胺属单分子层吸附：用80％的乙醇溶液作洗脱剂来洗脱吸附吡啶已达饱和的JDW-2树脂，效果是很理想的．在3．6个床体积内洗脱率达91．52％，4．8个床体积内洗脱率达到94．85％。表明酚醛型吸附树脂具有优良的洗脱性能．     

缩聚型邻苯二酚树脂的合成及对硼酸的吸附性能

合成了球状邻苯二酚－－甲醛树脂，并讨论了它对硼酸的吸附性能。结果表明，树脂可在中性和弱碱性条件下较好地吸附硼酸；测定了树脂蝗吸附等温曲线，树脂对硼酸的理论吸附量可达６．１４ｍｇ．Ｂ／ｇ干树脂，并且具有良好的动态吸附及洗脱性能。     

铜印迹螯合树脂对金属离子的吸附特性

研究了铜印迹螯合树脂与非印迹螯合树脂对金属离子的吸附性能，结果表明：铜印迹树脂对Cu^2 、Ni^2 、Zn^2 的吸附量比非印迹树脂有显著增大,两者对Cu^2 的吸附速率均较快，其表观吸附速率分别为0．044s^-1和0．040s^-1；印迹树脂对Cu^2 的吸附可用Langmuir或Freundlish等温式来描述；其动态吸附曲线与离子的起始浓度相关；用0．5mol／L HCl即可快速洗脱吸附的Cu^2 ，树脂具有较强的再生能力，可以重复使用。     

几种树脂对芦荟苦素的吸附性能

研究硅胶H和三种不同极性的大孔吸附树脂对芦荟苦素的吸附与洗脱性能，用静态实验筛选树脂、动态实验考察芦荟苦素提取液浓度、上样流速和温度对GD-10大孔吸附树脂吸附能力影响。结果表明GD-10吸附树脂对芦荟苦素的吸附能力较强，洗脱能力最好，且易于再生。     

吸附树脂AB—8对甜菊甙的吸附性能及在其提取纯化中的应用

考察了大孔吸附树脂ＡＢ－８对甜菊甙的吸附性能，和溶液的ＨＰ值，洗脱剂的种类及流速对树脂吸附，脱附性能的影响，结果表明，ＡＢ－８树脂对甜菊甙吸附量高，循环使用性能好且易于洗脱。     

THE SYNTHESIS AND CHARACTERIZATION OF SOME POROUS RESINS AND THEIR ADSORPTION PROPERTY ON STEVIA GLYCOSIDES

A series of porous resins (PYR) with different content of pyridyl group were prepared,and their physical structure and adsorption properties on the stevia glycosides were studied in detail.After the selective adsorption of PYR resins,the rebaudioside A could be separated from the other components of the stevia glycosides,and a new method for obtaining pure rebaudioside A is reported.     

THE SYNTHESIS AND CHARACTERIZATION OFSOME POROUS RESINS AND THEIR ADSORPTIONPROPERTY ON STEVIA GLYCOSIDES

1.INTRODUCTIONFromtheleavesofSteviaRebaudianaBertoni,asweetherbindigenoustoelevatedterrainonthebordersofBrazilandParaguay,eightsteviaglycosideshasbeenisolatedinayieldof10~15%andutilizedasahigh-sweetness,low-calorie,nonnutritionsweetener[1-3].Stevioside,rebaudiosideAandrebaudiosideCarepresentinthelargestquantitiesoftheeightsteviaglycosides.Amongthesethreeglycosides,rebaudiosideAisknownasthebestsweetenerwithrespecttotheintensityofsweetnessaswellasthequalityoftaSte,whiletheothertwomajorsw…     

大孔吸附树脂对银杏叶黄酮类化合物吸附及解吸的研究

本文介绍了DM－130，LSA－10和LSA－20型三种大孔吸附树脂对银杏叶黄酮类化合物的吸附性能，考察了pH值，温度，浸出液浓度等影响吸附性能的因素，结果表明DM－130型树脂对黄酮类化合物具有较好的吸附效果。     

Comprehensive characterization of Stevia Rebaudiana using two-dimensional reversed-phase liquid chromatography/hydrophilic interaction liquid chromatography

Two-dimensional reversed-phase liquid chromatography/hydrophilic interaction liquid chromatography (2D-RPLC/HILIC) system was successfully applied for comprehensive characterization of steviol glycosides from Stevia rebaudiana. The experiments were performed in offline mode using an XCharge C18 column in first dimension and an XAmide column in second dimension. In first dimension, preliminary separation of Stevia aqueous extract was accomplished and 30 fractions were collected. Then fractions 1-20 were selected for further purification and 13 compounds with high purity were obtained in second dimension. Comprehensive characterization of these compounds was completed by determination of their retention time, accurate molecular weight, diagnostic fragmentation ions, and nuclear magnetic resonance spectroscopy. As a result, all nine known steviol glycosides, as well as other four steviol glycosides were fully purified. The result demonstrated that this procedure is an effective approach for the preparative separation and comprehensive characterization of steviol glycosides in Stevia. This 2D-RPLC/HILIC method will be a promising tool for the purification of low-abundance compounds from natural products.     

Direct analysis of steviol glycosides from Stevia leaves by ambient ionization mass spectrometry performed on whole leaves

Leaf spray mass spectrometry is explored as a fast and simple way for direct analysis of sweet glycosides in fresh untreated Stevia leaves without sample pretreatment. In this technique, a fresh triangular piece of Stevia leaf serves as both sample and substrate. Application of a butanol : methanol : water mixture and a high voltage to intact leaf material produces a high electric field at the tip of the leaf. This results in field emission of charged droplets containing the glycosides. The resulting dry ions are detected by mass spectrometry and confirmed by tandem mass spectrometry and exact mass measurements. A comparison between leaf spray and other ambient ionization methods which are successful for screening glycosides in Stevia leaves--desorption electrospray ionization, low temperature plasma and paper spray--shows that leaf spray produces the highest quality spectra. It is also extremely easy to implement with no need for nebulizing gas or sample preparation and is suited to semi-quantitative determinations. The potential for the application of leaf spray mass spectrometry to direct and rapid screening of plant materials is here realized in the case of Stevia sweet glycosides.     

大孔吸附树脂提取银杏黄酮

银杏叶;黄酮类化合物;大孔吸附树脂提取银杏黄酮     

Characterisation of Stevia rebaudiana by comprehensive two-dimensional liquid chromatography time-of-flight mass spectrometry

Comprehensive two-dimensional liquid chromatography (LC x LC) connected on-line to electrospray ionisation time-of-flight mass spectrometry (ESI-TOF-MS) was employed for analysis of aqueous extract of Stevia rebaudiana. Different combinations of strong cation-exchange (SCX), amino (NH2), and octadecyl siloxane (C18) stationary phases were tested in the separation of all nine known sweet Stevia glycosides. A combination of C18 as the first-dimension column and NH2 as the second-dimension column fully separated all the glycosides from the matrix. The method proved to be quantitative and repeatable. The limit of detection (S/N=3) for stevioside, a widely used natural sweetener, was 43.4 ng/g in dry leaves. The RSD for retention times was <0.1% and that of peak areas 4.5%.     

基于离子交换树脂制备多孔氧化铝球及在非水体系中分离银杏内酯

以磺酸型大孔离子交换树脂D072为模板, 设计合成了球形的多孔氧化铝, 利用XRD、SEM和氮气吸附仪对其结构进行了表征. 以这种球形多孔氧化铝作为分离材料, 考察了其在非水体系中对银杏黄酮和银杏内酯的吸附选择性, 在最佳分离条件下, 制备了纯度为58.5%, 且不含任何黄酮的银杏内酯. 利用红外光谱法证明了吸附机理为配位吸附.     

Tandem mass spectrometric fragmentation patterns of known and new steviol glycosides with structure proposals

Stevia rebaudiana contains several steviol glycosides that have a sweet flavor. They are up to 450 times sweeter than sucrose, but some have an undesirable aftertaste. Up to 2010, ten different steviol glycosides have been described from the leaves or purified extracts of S. rebaudiana. In this paper, the tandem mass spectrometric fragmentation patterns of these ten compounds are compiled, along with a scheme for structural elucidation. This scheme is then applied to 12 steviol glycosides that have not yet been described. The proposed structures of five steviol glycosides have been confirmed by other authors.     

Approaches toward the Separation,Modification, Identification and Scale up Purification of Tetracyclic Diterpene Glycosides from Stevia rebaudiana (Bertoni) Bertoni

Stevia rebaudiana (Bertoni) Bertoni is a plant species native to Brazil and Paraguay well-known by the sweet taste of their leaves. Since the recognition of rebaudioside A and other steviol glycosides as generally recognized as safe by the United States Food and Drug Administration in 2008 and grant of marketing approval by the European Union in 2011, the species has been widely cultivated and studied in several countries. Several efforts have been dedicated to the isolation and structure elucidation of minor components searching for novel non-caloric sugar substitutes with improved organoleptic properties. The present review provides an overview of the main chemical approaches found in the literature for identification and structural differentiation of diterpene glycosides from Stevia rebaudiana: High-performance Thin-Layer Chromatography, High-Performance Liquid Chromatography, Electrospray Ionization Mass Spectrometry and Nuclear Magnetic Resonance Spectroscopy. Modification of diterpene glycosides by chemical and enzymatic reactions together with some strategies to scale up of the purification process saving costs are also discussed. A list of natural diterpene glycosides, some examples of chemically modified and of enzymatically modified diterpene glycosides reported from 1931 to February 2021 were compiled using the scientific databases Google Scholar, ScienceDirect and PubMed.