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研究了Pichia fermentans酵母菌产多糖YP5的单糖组成和结构。将酵母菌进行超声破碎后,采用乙醇沉淀法得到粗多糖,然后进行DEAE-纤维素色谱柱分离,得到均一的水溶性多糖YP5。经气相色谱分析表明,糖基由鼠李糖、阿拉伯糖、木糖、甘露糖、葡萄糖与半乳糖组成,其摩尔比为9.51∶1.33∶2.31∶0.94∶84.93∶0.96。乌氏粘度计法测得多糖的分子量为8.3×104。结合红外光谱和核磁共振1HNMR分析表明,该多糖YP5具有多糖特征性的红外吸收峰,存在酰胺结构,主要由β-D-葡聚糖组成。 相似文献
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建立了薄层色谱-紫外可见分光光度法测定纸张样品水解液中单糖组成的方法。纸张样品水解后点样在以丙酮处理过的硅胶G薄层板上,以正丁醇∶乙酸乙酯∶异丙醇∶乙酸∶吡啶∶水=7∶20∶12∶7∶6∶5(体积比)为展开剂,以苯胺-草酸为显色剂,测定了单糖的Rf值。以1-萘酚为显色剂,测定了纸张样品水解液中的单糖含量,方法的线性关系较好,5种单糖的样品加标回收率为96.10%~98.18%。该方法分离效果好,操作简便,可用于纸张样品水解液中5种单糖的同时测定,从而为法庭科学中纸张的检验提供依据。 相似文献
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提出了测定多糖样品中单糖含量的气相色谱法。10.00 mg多糖样品经0.4 mL4mol·L-1三氟乙酸溶液于100℃水解5h变为单糖,再进行乙酰化。所得溶液采用气相色谱法进行分离测定。以DB-5色谱柱为固定相,采用分流比为10∶1的分流模式进样。6种单糖的质量浓度在2.00~100.00mg·L-1内与其峰面积呈线性关系,检出限(3S/N)为0.11~0.18mg·L-1。按标准加入法进行回收试验,回收率为88.0%~110%,峰面积的相对标准偏差(n=6)为1.3%~2.3%。 相似文献
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气相色谱法测定芦荟及芦荟干粉中的多糖 总被引:1,自引:0,他引:1
提取芦荟及芦荟干粉样品中的多糖,将多糖水解为单糖之后衍生化反应,用气相色谱法进行分析,实验选择了最佳分离条件,以木糖醇为内标物,用OV-225与OS-138为色谱柱固定液,使衍生物得到了很好的分离,结果表明:未经水解的芦荟中含有少量的单糖以葡萄糖的形式存在,水解后的单糖主要为甘露糖和葡萄糖,这与用乙醇沉淀多糖后测定结果一致,即芦荟及芦荟干粉中的多糖主要为甘露聚糖和甘露葡聚糖。 相似文献
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气相色谱法测定芦荟及芦荟干粉中的多糖 总被引:4,自引:0,他引:4
用气相色谱法测定了芦荟及芦荟干粉样品中的多糖。实验以木糖醇为内标物,采用以OV-225与OS-138为固定液的色谱柱,使多糖水解为单糖后的衍生物得到了分离。结果表明:未经水解的芦荟中含有少量的单糖,主要为葡萄糖;水解后的单糖主要为甘露糖和葡萄糖。这与用乙醇沉淀多糖后的测定结果(即芦荟及芦荟干粉中的多糖主要为甘露聚糖和葡甘露聚糖)是一致的。 相似文献
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蒲黄多糖的研究 总被引:4,自引:0,他引:4
缪平 《高等学校化学学报》1990,11(12):1362-1366
蒲黄经热水提取,脱除蛋白质、乙醇沉淀,Sephadex G50柱层析分离,DEAE-Sephadex A25和DEAE-Cellulose离子交换柱层析分离得3种白色粉末状多糖TAA、TAB、TAC。经凝胶柱层析、醋酸纤维素薄膜电泳证明,三者为均一体。3种多糖经酸全水解、纸层析和气相色谱分析,确定了糖基的组成及摩尔组成比。用核磁共振、甲基化分析、NaIO_4氧化等方法对多糖结构进行了初步探讨。 相似文献
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Summary The chromatographic behaviour of anions on paper strips treated with tri-n-octylamine (TOA) salts or Aliquat 336 and developed with aqueous solutions of acetic, formic, monochloroacetic or trifluoroacetic acids and their sodium salts was investigated. Liquid-liquid extraction of organic acids by 0.1 M solution of TOA in benzene as well as the anion exchange between benzene solutions of TOA salts or Aliquat 336 (in acetate form) in benzene and aqueous solutions of sodium halides was also studied. It was found that extraction increases in the following order of the acids: CH3COOOH<HCOOH<CH2CICOOH<CF3COOH; the relative affinity of organic anions to the quaternary alkyl-ammonium cation also increase in a similar order. The extraction of acid in excess over the amount necessary to neutralize the amine was observed for all four acids. The RF values of anions investigated depend markedly on the type of organic acids or their salts and their concentration in the mobile phase. Halide ions are more strongly retained on paper treated with Aliquat 336 as compared with TOA salts. The chromatographic systems investigated offer many possibilities to separate various anion mixtures.Parts and II: refs. [1, 2]. 相似文献
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Meire R. Silva Felipe N. Andrade Bruno H. Fumes Fernando M. Lanças 《Journal of separation science》2015,38(17):3071-3083
The concept of unified chromatography has been in existence for 50 years after the work of Giddings proposing that all modes of chromatography (gas chromatography, liquid chromatography, supercritical fluid chromatography and so on) may be treated together under a single unified theory. His idea was partially fulfilled 23 years later by Ishii, Takeuchi and colleagues, who demonstrated for the first time the possibility to analyze a complex sample containing substances with a wide range of boiling points and polarities in the same instrument and column, just by varying the mobile phase pressure and temperature to change from one chromatographic mode to another. This approach has been demonstrated through application to the separation of complex mixtures in several areas including crude oil, edible oils and polymers. Still, unified chromatography has not yet been fully developed. In the present work, we will review the fundamentals, instrumentation and several applications of the technique. Also discussed are the drawbacks that still hinder development, as well as the recent developments and trends in instrumentation and columns that suggest the most feasible ways forward to the full development of unified chromatography. 相似文献
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Although there are many simple thin-layer chromatography (TLC) separations, many more are complex and involve more than a few components, that means having to use special high-performance TLC (HPTLC) plates or microspotting or banding devices to increase its resolving power if developing in only one direction. However, adding a second development to perform two-dimensional TLC (2D TLC) allows even better resolution of complex samples. This is because different modes of chromatography are being invoked by the use of one stationary phase with two mobile phases, bilayer plates, graft TLC, or multidimensional TLC. This paper is a review of recent applications that have benefitted from using 2D TLC in its various forms. They were chosen for their variety of sample types as well as the unique choices of plates and/or mobile phases made by the researchers to yield improved separations. 相似文献
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W. Gołkiewicz 《Chromatographia》1981,14(11):629-632
Summary A method is described and experimentally verified permitting the determination of the optimal gradient programs in HPLC on the basis of isocratic TLC data. The proposed method has many advantages and can also be used in reversed-phase systems. A satisfactory agreement between the theoretical and experimental of VR/VO values has been confirmed. Some discrepancies for more strongly retained solutes are, probably due to the respective equilibrium and nonequilibrium state of the column in isocratic and gradient elution.Part I: Ref. [1]. 相似文献
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O. Bobleter 《Chromatographia》1996,43(7-8):444-446
Summary In November 1995, theDeutsches Museum, the world's largest technical museum, opened a new branch in Bonn, devoted to achievements after 1945. There, the first gas chromatographic system used by Erika Cremer and Fritz Prior, in 1945–47, in Innsbruck, is exhibited. The new display is described and the early activities of Erika Cremer and her students are summarized. 相似文献
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研究了蛋白质纯化制备的二种运行模式,其一,在色谱柱超载下纯化制备蛋白质模式,并成功地用离子交换色谱纯化制备了大豆中的胰蛋白酶,用反相液相色谱纯化了细胞色素C;其二,用溶质-溶质顶替色谱纯化制备了核糖核酸酶-A,并对顶替色谱过程中诸参数进行了讨论和选择。 相似文献