高效液相色谱法测定大蒜及其制品中的大蒜素

采用人工合成的大蒜素做为标准品，建立了高效液相色谱法直接测定大蒜及其制品中的大蒜素含量的方法。使用Ｓｐｈｃｒｉｓｏｂ　ＯＤＳ２色谱柱，流动相为甲醇＋水＝６０＋４０，检测波长２５４ｎｍ，进样体积２５μＬ。大蒜素最小检测量为 ２．０ ｍｇ／Ｌ，相对标准偏差为２．８％，回收率为９０．４％～１０３．０％，线性范围为 ０～１２０ｍｇ／Ｌ     

选择离子流动管质谱法测定大蒜酶解液顶空中17种有机硫化合物

采用选择离子流动管质谱(SIFT-MS)法,顶空取样后,以H3O+,NO+或O2+为初始离子,定量分析了17种大蒜酶解液挥发性有机硫化合物。结果表明:有机硫化合物主要为二烯丙基硫醚、甲基烯丙基硫醚、硫代亚磺酸酯和硫醇,其中二烯丙基二硫醚浓度为137 g/m3,二烯丙基三硫醚浓度为13.4 g/m3,甲基烯丙基二硫醚浓度为8.98 g/m3,它们分别占17种有机硫化合物总含量的77.3%,7.58%和5.08%(相对含量);本研究采用顶空取样方法测出大蒜素的浓度为5.63 g/m3,相对含量为3.20%。     

Purification and Characterization of a Cu,Zn-SOD from Garlic (Allium sativum L.). Antioxidant Effect on Tumoral Cell Lines

Crude garlic extract contains one Mn-superoxide dismutase designated as SOD1 and two Cu,Zn superoxide dismutases as SOD2 and SOD3. The major isoform SOD2 was purified to homogeneity by Sephacryl S200-HR gel filtration, DEAE Sepharose ion exchange chromatography, and chromatofocusing using PBE 94. SOD2 was purified 82-fold with a specific activity of 4,960 U/mg protein. This enzyme was stable in a broad pH range from 5.0 to 10.0 and at various temperatures from 25 to 60°C. The native molecular mass of SOD2 estimated by high performance liquid chromatography on TSK gel G2000SW column was 39 kDa. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis analysis showed a single band near 18 kDa, suggesting that native enzyme was homodimeric. The isoelectric point as determined by chromatofocusing was 5. Analysis of its N terminal amino acid sequence revealed high sequence homology with several other cytosolic Cu,Zn-SODs from plants. Exposure of cancer cell lines to garlic Cu,Zn-SOD2 led to a significant decrease in superoxide content with a concomitant rise in intracellular peroxides, indicating that the enzyme is active in mammalian cells and could, therefore, be used in pharmacological applications.     

山蜡梅叶颗粒的高效液相色谱指纹图谱定性及定量分析

应用高效液相色谱法建立可同时对山蜡梅叶颗粒进行鉴别和有效成分含量测定的色谱指纹图谱。以Cosmosil C18色谱柱为分离柱,甲醇与甲酸混合溶液进行梯度洗脱,检测波长为365 nm。成分芦丁、槲皮素和山奈素的质量浓度均与峰面积呈线性关系,线性范围分别为4.6~110.4,1.0~24.0,1.5~36.0 mg.L-1。运用中药色谱指纹图谱相似度评价系统2004版进行分析,20批样品平均相似度为95%以上。颗粒剂中三个成分的含量分别为芦丁含量(130±20)μg.g-1,槲皮素含量(35±10)μg.g-1,山奈素含量(60±10)μg.g-1。建立的山蜡梅叶颗粒的色谱指纹图谱,为质量控制提供新方法。     

测定雨生红球藻中虾青素及其它色素含量的高效液相色谱法

建立了一种分离和测定雨生红球藻中虾青素和其它色素的反相高效液相色谱法 ;含有雨生红球藻细胞的培养液经离心分离 ,匀浆破碎 ,用甲醇 -二氯甲烷 (体积比3∶1)提取色素 ,提取液用HPLC分离测定 ;分析柱为Nova_PakC18(300mm×3.9mmID ,5μm)柱 ,流动相为水、甲醇和丙酮 ,流速1.0mL/min ,用二极管阵列检测器在250～700nm波长范围扫描 ,在476nm处进行检测 ;虾青素、多种类胡萝卜素和叶绿素在30min内得到较好分离 ,其中游离虾青素、斑蝥黄质和 β_胡萝卜素的检出限分别为3.56、1.36和29.4μg/L,这3种类胡萝卜素分别在质量浓度为1.99～31.7mg/L、2.44～39.0mg/L、2.25～36.0mg/L范围内与峰面积线性关系良好 ,相关系数分别为0.9993、0.9987和0.9778;该法的精密度 (RSD为0.09 %～2.97% )和回收率(96%～102 % )均符合方法学要求 ,可以用于研究和测定雨生红球藻中虾青素和其它色素的含量     

烃基磷(膦)酸酯的化学结构及其液相色谱行为

本文研究了各种烷基或芳基磷(膦)酸酯和亚磷(膦)酸酯的化学结构对其在高效液相色谱(HPLC)柱上保留作用的影响. HPLC中容量因子与化合物的类型以及烷基碳原子数有密切关系. 我们讨论了这些化合物的化学结构和它们的容量因子的关系.     

HPLC Determination of Amino And Carbonyl Compounds with Dabsyl Chloride and Dabsyl Hydrazine

The new chromophoric reagent, 4-dimethylaminoazobenzene-4′-sulfonyl chloride (dabsyl chloride) was synthesized by reaction of sodium 4-dimethylaminoazobenzene 4′-sulfonate with phosphorus pentachloride. Dabsyl chloride reacted rapidly with all amino acids, aliphatic amines, and polyamines to form the corresponding dabsyl derivatives. The dabsyl amino acids (10^?11 mol) were visualized on thin layer plates and found to be photo-stable. During the last 12 years, in combination with HPLC, this newly developed labeling reagent has been shown to be very promising for microdetermination of amino acids, aliphatic amines and polyamines. Recently, another new chromophoric reagent, dabsylhydrazine, was synthesized from the reaction of dabsyl chloride with hydrazine. This reagent reacted readily with monosaccharides and carbonyl compounds to form the corresponding chromophoric dabsylhydrazones with strong absorbance at 425 nm. The application of this new reagent in HPLC analysis of monosaccharides was discribed. By use of Nova-PAK C₁₈ reverse-phase column and a concave gradient system of water and acetonitrile as eluent, the detection limits of monosaccharides in the range of 10 pmol have been reached.     

叶绿宝和霉敌乳剂中有效成分的HPLC测定

用反相液相色谱分离测定了叶绿宝和霉敌乳剂中的有效成分1,2 苯并异噻唑啉酮(霉敌)的含量。方法采用Shim - packCLC -CN色谱柱和甲醇 -磷酸盐缓冲液为流动相。讨论了最佳色谱条件。测定的线性范围为0.1～5μg,相关系数为r=0.9999,霉敌乳剂回收率为 (99.3±0.5) % ,叶绿宝的回收率为 (99.7±0.6) %。     

Isolation of aromatic compounds from a coal extract by semipreparative HPLC

Summary Two methyldibenzofuran isomers and a tetramethylnaphthalene isomer have been isolated from the organic extract of a Sakoa (southwest Madagascar) coal and were positively identified by IR spectroscopy. The isolation procedures were carried out on a semipreparative scale and included two to four normal-phase HPLC steps and a reversed-phase HPLC step. Reproducibility of the normal-phase fractionations on alumina was enhanced by an improved moisture-control system. Substantial enrichment of the compounds of interest was achieved in each step, as evidenced by capillary GC.     

基于水溶性浸出物及HPLC指纹图谱评价不同贮存年限半夏的品质

研究不同贮存年限半夏药材的浸出物,建立浸出物的HPLC特征指纹图谱,为半夏药材品质评控提供参考。浸出物测定方法采用药典法;HPLC指纹图谱的色谱条件:采用C_(18)色谱柱(150 mm×4.6 mm,5μm),以水–甲醇为流动相,梯度洗脱,流量为0.8 m L/min,检测波长为260 nm,柱温为25℃,进样体积为50μL。采用相似度评价及聚类分析技术揭示14批样品的相似性及差异性。14批半夏浸出物有12批合格,2批不合格。建立14批半夏浸出物样品的高效液相指纹图谱,确定了3个共有峰,共有峰保留时间的相对标准偏差小于2%,峰面积的相对标准偏差差异较大。1~#~7~#半夏样品有12个共有峰,共有峰保留时间的相对标准偏差小于1.5%,峰面积的相对标准偏差差异较大。各批次药材化学成分组成及含量均存在一定差异。以半夏浸出物数据与其高效液相色谱指纹图谱数据为基础,将指纹图谱相似度评价与聚类分析结合起来,用浸出物含量及评价软件测评结果对半夏品质进行综合评估,可以更精确地对半夏药材进行质量控制。     

Phytochemical composition,antioxidant activity and HPLC profiles of Swertia species from Western Ghats

Swertia chirayita is one of the potential medicinal plants of the family Gentianaceae in traditional medicine. Due to its high demand and scarcity, trade of chirayita is affected by adulterants. Swertia species from Western Ghats were compared with S. chirayita for phytochemical characterisation and antioxidant activities by using different extracts. This study revealed that acetone is the best extraction solvent of phenolic and flavonoid compounds with antioxidant properties as compared with other extracts. S. chirayita showed better antioxidant activity than other species with highest content of phenolics and flavonoids. Among the species from Western Ghats, Swertia minor has better antioxidant properties with higher content of phenolics and flavonoids when compared with S. chirayita. Gallic acid was detected in all species under study by using HPLC analysis. The Swertia species under study showed similar phytochemical properties and antioxidant potential and hence their use as substitute to S. chirayita needs to be further investigated.     

Quantification of Chemical Groups and Quantitative HPLC Fingerprint of Poria cocos (Schw.) Wolf

(1)Objective: In this study, a quantitative analysis of chemical groups (the triterpenoids, water-soluble polysaccharides, and acidic polysaccharides) and quantitative high liquid performance chromatography (HPLC) fingerprint of Poria cocos (Schw.) Wolf (PC) for quality control was developed. (2) Methodology: First, three main chemical groups, including triterpenoids, water-soluble polysaccharides, and acidic polysaccharides, in 16 batches of PC were evaluated by ultraviolet spectrophotometry. Afterward, the quantitative fingerprint of PC was established, and the alcohol extract of PC was further evaluated. The method involves establishing 16 batches of PC fingerprints by HPLC, evaluating the similarity of different batches of PC, and identifying eight bioactive components, including poricoic acid B (PAB), dehydrotumulosic acid (DTA), poricoic acid A (PAA), polyporenic acid C (PAC), 3-epidehydrotumulosic acid (EA), dehydropachymic acid (DPA), dehydrotrametenolic acid (DTA-1), and dehydroeburicoic acid (DEA), in PC by comparison with the reference substance. Combined with the quantitative analysis of multi-components by a single marker (QAMS), six bioactive ingredients, including PAB, DTA, PAC, EA, DPA, and DEA, in PC from different places were established. In addition, the multivariate statistical analyses, such as principal component analysis and heatmap hierarchical clustering analysis are more intuitive, and the visual analysis strategy was used to evaluate the content of bioactive components in 16 batches of PC. Finally, the analysis strategy of three main chemical groups in PC was combined with the quantitative fingerprint strategy, which reduced the error caused by the single method. (3) Results: The establishment of a method for the quantification of chemical groups and quantitative HPLC fingerprint of PC was achieved as demonstrated through the quantification of six triterpenes in PC by a single marker. (4) Conclusions: Through qualitative and quantitative chemical characterization, a multi-directional, simple and efficient routine evaluation method of PC quality was established. The results reveal that this strategy can provide an analytical method for the quality evaluation of PC and other Chinese medicinal materials.     

Enhancing and inhibiting effects of aromatic compounds on luminol-dimethylsulfoxide-OH(-) chemiluminescence and determination of intermediates in oxidative hair dyes by HPLC with chemiluminescence detection

The effect of 36 aromatic compounds on the luminol-dimethylsulfoxide-OH⁻ chemiluminescence (CL) was systematically studied. It was found that dihydroxybenzenes, and ortho- and para-substituted aminophenols and phenylenediamines inhibited the CL and phenols with three or more than three hydroxyls except phloroglucin tended to enhance the CL. The CL inhibition and enhancement was proposed to be dependent on whether superoxide anion radical (O₂⁻) was competitively consumed by compounds in the CL system. Trihydroxybenzenes were capable of generating superoxide anion radical, leading to the CL enhancement, whereas dihydroxybenzenes were superoxide anion radical scavenger, causing the CL inhibition. Based on the inhibited CL, a novel method for the simultaneous determination of p-phenylenediamine, o-phenylenediamine, p-aminophenol, o-aminophenol, resorcinol and hydroquinone by high-performance liquid chromatography coupled with chemiluminescence detection was developed. The method has been successfully applied to determine intermediates in oxidative hair dyes and wastewater of shampooing after hair dyed.     

Chiral HPLC and physical characterisation of orthoconic antiferroelectric liquid crystals

New orthoconic antiferroelectric liquid crystalline materials were synthesised and characterised in their racemic forms and as (S) enantiomers. The materials possess oligo-methylene spacers of different lengths in semi-fluorinated achiral chains and lateral substitution by fluorine at two different positions of the molecular core. For comparison purposes, analogical materials without fluorine lateral substitutions were also prepared. Polysaccharide chiral stationary phases based on two different chiral selectors were used for the separation of the enantiomers of the individual racemic mixtures by high-performance liquid chromatography. A baseline separation of (S) and (R) enantiomers was obtained for four of the six studied liquid crystalline materials. Two of the materials were partially separated under the optimised separation conditions. The elution order of the individual enantiomers in the racemic mixtures was successfully assigned, as pure (S) enantiomers of all the studied materials were available. Both the position of the fluorine atom within the molecular core and the size of the achiral moiety had significant effects on the separation of the individual enantiomers of the studied compounds. Moreover, it was also found that the structure of the chiral stationary phase selector significantly influenced the enantiomeric resolution.     

Characterization and Reactivity of a Tetrahedral Copper(II) Alkylperoxido Complex

A tetrahedral Cu^II alkylperoxido complex [Cu^II(TMG₃tach)(OOCm)]⁺ ( 1^OOCm ) (TMG₃tach={2,2′,2′′-[(1s,3s,5s)-cyclohexane-1,3,5-triyl]tris-(1,1,3,3-tetramethyl guanidine)}, OOCm=cumyl peroxide) is prepared and characterized by UV/Vis, cold-spray ionization mass spectroscopy (CSI-MS), resonance Raman, and EPR spectroscopic methods. Product analysis of the self-decomposition reaction of 1^OOCm in acetonitrile (MeCN) indicates that the reaction involves O−O bond homolytic cleavage of the peroxide moiety with concomitant C−H bond activation of the solvent molecule. When an external substrate such as 1,4-cyclohexadiene (CHD) is added, the O−O bond homolysis leads to C−H activation of the substrate. Furthermore, the reaction of 1^OOCm with 2,6-di-tert-butylphenol derivatives produces the corresponding phenoxyl radical species (ArO^.) together with a Cu^I complex through a concerted proton-electron transfer (CPET) mechanism. Details of the reaction mechanisms are explored by DFT calculations.     

对羟基苯甲醛的溴化及甲氧基取代反应液的高效液相色谱分析法

应用高效液相色谱技术，在正相硅胶柱上对时羟基苯甲醛滇化及甲氧基取代反应液进行内标法定性定量分析。流动相采用含１％冰醋酸的二氯甲烷，内标物采用对硝基苯酚，紫外检测波长为２７０ｎｍ。     

Determination of carbonyl compounds in the atmosphere of charcoal plants by HPLC and UV detection

A chromatographic quantification method with two different mobile phases (elution conditions 1 and 2) was developed to determine carbonyl compounds (CCs) in air samples collected from charcoal production workplaces, using C18 cartridges coated with 2,4-dinitrophenylhydrazine (DNPHi). Several 2,4-dinitrophenylhydrazones (DNPHo) were separated and quantified using an HPLC system and UV detection. In 16 min, elution condition 1 successfully separated and quantified the DNPHo of 14 CC including acetaldehyde, acrolein, formaldehyde, and furfural, and estimated the sum of C4 isomers, butanal-isobutanal-butanone. This elution condition was able to resolve the pairs acrolein/furfural and propanone/propanal, which have been cited in the literature as difficult mixtures to be separated. The elution condition 2 allowed separation and quantification, in less than 30 min, of 13 out of the 17 CC listed above. This elution condition was also able to separate propanone from propanal and butanone from the other components of the C4 mixture. When the two mobile phases were used together, they allowed confirmation of the presence of the DNPHo in the real samples. Thus, both elution conditions have been shown to be appropriate to determine CC, in personal and stationary samples, collected in charcoal production plants.     

动力学分析法研究生物反应活性中间体及其相关反应

评述了动力学分析法研究生物反应活性中间体的意义，存在的困难，研究方法及近年来 一多学科交叉与渗透领域的研究进展。