防风多糖化学成分的研究

从中药防风Saposhnikovia divaricata（Turcz．）Schichk中分离得到两种酸性杂多糖SPSa和SPSb,经凝胶渗透色谱证实为均一组分．UV-Vis光谱证实两种多糖中不含蛋白质．采用薄层色谱和毛细管电泳色谱确定了SPSa和SPSb中单糖的组成及摩尔比,SPSa：半乳糖：阿拉伯糖：鼠李糖：半乳糖醛酸=1：2．3：0．15：4．8;SPSb：半乳糖：阿拉伯糖：鼠李糖：木糖：半乳糖醛酸=1：1．5：0．8：0．2：10．2．采用IR光谱对多糖进行了初步结构研究．与现有的防风多糖的组成相比较,确定出SPSa和SPSb为新的防风多糖．     

Physico‐chemical Properties and Bioactivities of a Glycoconjugate LbGp5B from Lycium barbarum L

A glycoconjugate designated as LbGp5B was isolated from the fruit of Lycium barbarian L. and purified to homogeneity by gel filtration. LbGpSB is composed of rhamnose (Una), arabinose (Ara), galactose (Gal), glucose (Glc), galacturonic add (GalA) and seventeen amino adds. The molecular weight of LbGpSB was determined by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE) and by matrix‐assisted laser desorption/ionization (MALDI) time of fight (TOF) mass spectrometry (MS). The preliminary experiments showed that LbGpSB promoted splenocyte proliferation in mice and inhibited the peroxidation of low density lipoprotein (LDL).     

Preparation, separation and degradation of oligouronides produced by the polygalacturonic acid transeliminase of Bacillus pumilus.

Production of the end products of polygalacturonic acid degradation on a large scale was done by reacting free galacturonic acid with Bacillus pumilus polygalacturonic acid transeliminase (PATE, EC 4.2.2.2) to obtain a mixture of the barium salts of several oligouronides. Small amounts of the unsaturated oligouronides were separated by paper chromatography. Large quantities of unsaturated oligouronides were separated on a AG-1-X8 (formate) column by applying a sample of mixed oligouronides and stepwise elution was carried out with sodium formate buffer (pH 4.7). The unsaturated oligouronides were identified on the basis of chromatographic mobilities, Sephadex gel filtration data, COOH/CHO ratio, thiobarbituric acid-reacting material, bromine uptake, and chemical and enzymatic degradation data as unsaturated tri-, tetra-, and hexagalacturonic acids. The chemical degradation of these unsaturated oligouronides, done with 6 N HCl by heating at 100 degrees for 30 min, gave qualitatively identical products of hydrolysis. These products compared with authentic standards, were identified as galacturonic acid, formic acid, 5-formyl-2-furancarboxylic acid, and 2-furancarboxylic acid. Analysis of the enzymatic breakdown products of the higher unsaturated uronides showed that a minimum of four galacturonic acid units was required for the action of purified endo-PATE from B. pumilus. The unsaturated trimer was not attacked, thus accounting for its accumulation as the major end product of polygalacturonate degradation by this enzyme.     

山茱萸酸性多糖FCP5-A的分离纯化与结构表征

从山茱萸中提取出水溶性粗多糖, 经柱色谱分离纯化得到一种酸性多糖组分FCP5-A. 采用高效凝胶渗透色谱法(HPGPC)测定其为均一性多糖, 平均分子量为8.7×104. 经IR、GC、部分酸水解、13C NMR及甲基化分析等方法对该多糖的化学结构进行了表征. 结果表明, 该多糖由鼠李糖、阿拉伯糖、半乳糖及半乳糖醛酸组成, 其摩尔比为1∶5.7∶0.6∶1.2. FCP5-A为多分支结构, 由-2)Rha(1-及-4)GalA(1-构成主链, 在鼠李糖的4位存在分支; 支链主要由高度分支的阿拉伯糖构成, 此外还存在-3)Gal(1-; 末端残基为Ara(1-及Gal(1-. 结果提示, FCP5-A为一种新的山茱萸酸性分支多糖.     

桑叶多糖SJB的结构分析和蛋白酪氨酸磷酸酯酶PTP1B抑制活性

通过DEAE-纤维素和凝胶过滤柱色谱对桑叶碱提粗多糖进行分级分离, 获得均一多糖SJB, 进行结构鉴定. 采用蛋白酪氨酸磷酸酯酶PTP1B体外模型对SJB进行降血糖活性测定. 结果表明: SJB的相对分子质量为5.4×104, 由鼠李糖、阿拉伯糖、葡萄糖、半乳糖、半乳糖醛酸组成的酸性杂多糖; 主链由1,2-、1,2,4-连接的鼠李糖和1,4-、1,3,4-连接的半乳糖醛酸组成; 侧链包括末端、1,5-、1,3,5-连接的阿拉伯糖; 末端、1,4-连接的葡萄糖以及末端、1,3-、1,4-、1,6-连接的半乳糖, 主要通过鼠李糖的O4位和半乳糖醛酸的O3位与主链相连. 该多糖为首次从桑叶中获得的酸性杂多糖. 20 μg/mL SJB对PTP1B的抑制率为31.7%.     

Rapid large-scale preparation of polysaccharides from jackfruit peel waste by high-speed countercurrent chromatography and their antioxidant and hypoglycemic activities

Polysaccharides with antioxidant and hypoglycemic activities were first isolated from jackfruit (Artocarpus heterophyllus Lam.) peel through the one-step high-speed countercurrent chromatography. The separation process was completed using the polymer two-phase aqueous system constituted by PEG1000-K₂HPO₄-KH₂PO₄-H₂O (0.8:1.25:1.25:6.5, w/w). For every separation process, two main polysaccharides, namely, fraction-1 and fraction-2 (165 and 225 mg, respectively) were obtained from a 2.0 g crude sample. As suggested by high-performance gel permeation chromatography, jackfruit peel polysaccharides had the mean molecular weight values of 113.3 and 174.3 kDa, separately. Physicochemical analysis suggested that two polysaccharides were dominant in galacturonic acid, galactose, rhamnose, arabinose, glucose, mannose, as well as fucose, which were highly esterified. Biological activity analysis showed that fraction-1 exhibited stronger antioxidant activity in vitro and hypoglycemic activity in streptozotocin-induced diabetic mice compared with fraction-2. The results suggest that polysaccharide fraction-1 may be developed as a potential functional food supplement.     

Characterisation of natural polysaccharides (plant gums) used as binding media for artistic and historic works by capillary zone electrophoresis

The monosaccharide constituents of plant gums were separated by capillary electrophoresis at pH 12.1 and detected with indirect UV absorbance. The plant gums investigated were gum arabic, gum acacia, gum tragacanth, cherry gum and locust bean gum (carob gum). The monosaccharides obtained after hydrolysis with 2M trifluoroacetic acid and lyophilisation of the hydrolysate were arabinose, galactose, mannose, rhamnose, xylose, fucose, and glucose, and the two sugar acids galacturonic and glucuronic acid, in accordance with the literature. They were separated in a background electrolyte consisting of NaOH to adjust the pH, 20 mM 2,6-pyridinedicarboxylic acid as chromophore for detection and 0.5 mM cetyltrimethylammonium bromide as additive to reverse the electroosmotic flow. Based on their electropherograms, the plant gums could be identified by their typical composition (depicted in a decision scheme) as follows: a peak of glucuronic acid, together with that of rhamnose, is indicative for gum arabic. Peaks of galacturonic acid and fucose point to gum tragacanth. Locust bean gum shows a major peak for mannose (with the concomitant galactose peak in ratio 4-1), whereas a glucuronic acid and a mannose peak together with a prominent arabinose peak indicates cherry gum. The method was applied to identify the plant gums in samples like watercolours and in several paint layers like gum tempera or those with egg white or drying oils as additives. Artificial aging experiments of thin layers of gum arabic on paper or glass carried out with UV-A radiation (366 nm) did not result in changes of the saccharide patterns, in contrast to the simultaneously conducted aging of a drying oil layer.     

Separation of trimethylsilylated oximes of monosaccharides by capillary gas-liquid chromatography

Summary Trimethylsilylated oximes (TMS-oximes) of arabinose, fucose, galactose, glucose, mannose, rhamnose, xylose, glucuronic acid, and galacturonic acid were prepared using a two-step derivatization procedure. The TMS-oximes were separated and quantitated by gas-liquid chromatography using a 25-m fused-silica capillary column coated with crosslinked methylsilicone stationary phase. Starting with dried sugar extract, the entire procedure can be accomplished within 2 hours.     

Polysaccharides ofPlantago major

Summary 1. The partial hydrolysis of the polysaccharide of the leaves ofPlantago major L. has given degraded pectic acid.2. A study of the physicochemical properties and IR spectra of the polygalacturonide and the products of its periodate-nitric acid oxidation has shown that the galacturonic acid residues in degraded pectic acid are in the pyranose from and are linked by a-0-1-4 bonds.Khimiya Prirodnykh Soedinenii, Vol. 3, No. 2, pp. 80–83, 1967     

Simultaneous determination of uric acid and creatinine in biological fluids by column-switching liquid chromatography with ultraviolet detection

A column-switching liquid chromatographic method for the simultaneous determination of uric acid and creatinine in human serum and urine was developed. Creatinine and uric acid were separated by size-exclusion chromatography on a hydrophilic gel column (C1) and creatinine eluted from Cl was separated from proteins by filtration through a longer hydrophilic gel column (C2). The creatinine fraction eluted from C2 was transferred to a weakly acidic cation-exchange column (C3) and then to a strongly acidic cation-exchange column (C4). Uric acid eluted from Cl after creatinine was transferred to an anion-exchange column (C5) and then to a hydrophilic gel column (C6). The mobile phase was a mixed buffer of pH 5.1 (propionic acid-succinic acid-NaOH, 60:15:60 mmol/1 in water). Diluted serum and urine could be injected onto C1, and Cl was backflushed after the transfer of uric acid from Cl to C5.

Creatinine and uric acid in the eluate were determined by measuring their ultraviolet absorption at 234 and 290 nm, respectively. The recovery of uric acid and creatinine added to diluted serum (20-fold dilution, concentration 20 and 5 μmol/1, respectively) was 98.9±0.56% and 100.9±1.29%, respectively. The recovery of uric acid and creatinine added to diluted urine (100-fold dilution, concentration 50 and 100 μmol/l, respectively) was 99.4±0.72% and 98.7±1.45%, respectively (mean±R.S.D., n=6).     

Synthesis of polymerizable poly(alkenoic acid)s via reversible addition fragmentation transfer polymerization for dental applications

The novel polymerizable poly(alkenoic acid)s 1a–1c (expected = 2500, 5000, and 10,000 g/mol) were synthesized in three steps starting from tert‐butyl acrylate. A RAFT polymerization using 2,2‐(thiocarbonylbis(sulfanediyl))bis(2‐methylpropanoic acid) 4 as a chain transfer agent, followed by a Mitsunobu esterification and a deprotection of the tert‐butyl ester groups with trifluoroacetic acid, provided the desired acidic polymers in moderate to good yields. The synthesized polymers were characterized by ¹H NMR spectroscopy and by gel permeation chromatography. The number‐average molecular weights measured for 1a–1c were in good agreement with the expected values. Self‐etch adhesives (SEAs) based on poly(alkenoic acid)s 1a–1c were formulated in order to investigate their adhesive properties. The addition of 1a–1c to a SEA formulation containing 10‐methacryloyloxydecyl dihydrogen phosphate resulted in a strong increase of the shear bond strength (SBS) of a dimethacrylate‐based composite to dentin. No significant influence of the polymer molecular weight on the dentin and enamel SBS was observed. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1814–1821     

Extraction, Purification and Anti-tumor Activity of Polysaccharide from Mycelium of Mutant Cordyceps Militaris

A water-soluble polysaccharide(named MCMP) was isolated from the mycelium with high yield mutation Cordyceps militaris by hot-water extraction, deproteinization by sevage, alcohol precipitation, anion-exchange and gel filtration chromatography CL-6B. The polysaccharide contained mannose, rhamnose, galactose and glucose in a molar ratio of 59.36:1:8.31:39.50, of which the average molecular weight is 8100. In our research, Hep-G2 cells, Hela cells and mesangial cells were chosen to determine the anti-tumor activity of the polysaccharide. The results of MTT assay show that polysaccharides of the mutant strain presented inhibitory activity on the cells proliferation after 48 h incubation.     

Isolation,purification and structural characterization of a water-soluble polysaccharide HM41 from Halenia elliptica D. Don

A water-soluble polysaccharide, HM_(41), was obtained from Halenia elliptica D. Don by acidic ethanol fractionation and gel filtration. Its homogeneity was confirmed by chromatography using multiple systems. HM_(41) was composed of rhamnose(Rha), arabinose(Ara), xylose(Xyl), mannose(Man),galactose(Gal), glucose(Glc) with a molar ratio of 1.0:5.5:1.8:3.0:9.4:21. The average molecular weight of HM_(41) was approximately 1.17 * 10~4. Periodate oxidation, Smith degradation, methylation and GC, IR,NMR, XRD, GC–MS analysis were used for the structural analysis of HM_(41). Its main chain was composed mainly of β-(1→4)Gal, β-(1→4)Glc and β-(1→6)Glc. β-(1 →4)Gal were substituted at 6-O and on average there were 14 branches among 23 main chain residues;(1→ 4)Glc had no branch;(1→6)Glc were substituted at 3-O and on average there were 9 branches among 14 main chain residues. The side chain was composed of(1→3,6)-Rha,(1→4)/(1→5)-Ara,(1 →4)/(1→5)-Xyl,(1→4,6)-Man and(1→2)-Glc. The terminal residue was composed of Ara, Xyl, Man, Gal, and Glc. Then, we demonstrated that HM and HM_(41) had strong scavenging activities in vitro hydroxyl. Overall, HM and HM_(41) may have potential applications in the antioxidants for medical and food industry.     

Simultaneous Determination of Aldoses and Uronic Acids of Citrus Pectin by LC with Precolumn Derivatization and UV Detection

The simultaneous determination of aldoses and uronic acids is now available by liquid chromatography. The procedure involves acid hydrolysis followed by derivatization with 3-amino-9-ethylcarbazole, which was first employed for aldoses and uronic acids derivatization. The usefulness of this method is seen in the ability to analyze commercially available citrus pectin. The results show that citrus pectin consists of xylose, glucose, arabinose, rhamnose, galactose and galacturonic acid in molar ratios of 0.3:1.0:1.8:2.8:7.4:50.9, which was consistent with the result obtained by GC. The described method is suitable for routine analysis of pectin or other polysaccharides containing uronic acids.     

Polysaccharides from the stems ofAlthea nudiflora

From the heart of the stems of the hollyhockAlthea nudiflora (Lindl.) Boiss., growing on the territory of Southern Kazakhstan we have isolated a polysaccharide (yield 5%) containing residues of glucuronic and galacturonic acids (totalling 42%), and also of glucose, rhamnose, galactose, arabinose, xylose (traces) and mannose (traces). From the bark of the stems of this plant we have isolated a polysaccharide (yield 1.8%) consisting of a branched polymer composed of residues of rhamnose, glucose, and arabinose (22:17:2) and also of glucuronic and galacturonic acids (totalling 30%). In the products of the methylation of this polysaccharide previously reduced at the COOH groups we have established the presence of 2,3,4-tri-O-methylrhamnose, 3,4-di-O-methylrhamnose, 2,3,4,6-tetra-O-methylglucose, 2,6-di-O-methylglucose, and a mixture of 2,3,6-tri-O-methylglucose and 2,3,6-tri-O-methylgalactose (1:10:14:5:7).V. L. Komarov Botanical Institute, Academy of Sciences of the USSR, Leningrad. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 145–148, March–April, 1980.     

超高效液相色谱-串联质谱法测定螺旋藻多糖的单糖组成

建立了同时测定螺旋藻多糖水解产物中鼠李糖、木糖、阿拉伯糖、果糖、甘露糖、葡萄糖、半乳糖、甘露醇、核糖、岩藻糖、葡萄糖醛酸、半乳糖醛酸12种糖类化合物的超高效液相色谱-串联质谱分析方法。螺旋藻样品经超声波辅助提取,用三氟乙酸水解,经Waters Acquity BEH Amide色谱柱(100 mm×2.1 mm,1.7μm)分离,以10mmol/L甲酸铵和10 mmol/L甲酸铵-乙腈为流动相,在电喷雾电离源负离子(ESI-)模式下,用多反应监测(MRM)模式检测。结果表明,12种糖类化合物的定量限为0.005~0.15 mg/kg,线性范围为0.05~5 mg/L。按照样品中每种糖本底含量的50%、100%、150%进行添加,回收率为80.21%~121.6%。应用该方法对螺旋藻样品进行分析,结果发现:大部分样品都能检测到岩藻糖、半乳糖、阿拉伯糖、鼠李糖、葡萄糖、果糖、木糖、核糖,含量在0.3~889.4 mg/g之间。此外,测定的15个样品中岩藻糖、半乳糖、阿拉伯糖、鼠李糖、葡萄糖、果糖、木糖、核糖是共有组分,含量差异较大,但在所有样品中均未检测到甘露醇和甘露糖。该方法的建立可为阐明螺旋藻多糖的结构组成及其活性提供技术支撑及基础数据。     

Comparative Analysis of Polysaccharides from Two Ecological Types of Leymus chinensis

Leymus chinensis(Trin.) Tzvel., widely distributed at eastern Eurasian steppe and divided into gray-green type and yellow-green type, has different stress resistance to environment. In the present study, the water-soluble polysaccharides from two ecotypes of L. chinensis were analyzed in detail, and the differences between polysaccharides from the two ecotypes of L. chinensis in the yield, monosaccharide composition, molecular weight and structure were clarified. The polysaccharides of L. chinensis were composed of both neutral and acidic polysaccharides. The neutral polysaccharides contained mannose, glucose, galactose, xylose and arabinose, and mainly consisted of β-1,4-Glcp, α-1,3-Galp and α-1,2-Xylp residues. The acidic polysaccharides contained mannose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, xylose and arabinose. However, the yields, monosaccharides contents and the molecular weights of the polysaccharides from the two ecotypes of L. chinensis were different. Moreover, the resistance type(gray-green type) of L. chinensis contained a number of α-1,3-Manp and reducing end of β-Glcp residues, and much more O-methyl groups than normal type(yellow-green type) of L. chinensis. The differences of the polysaccharides of the two ecotypes of L. chinensis might be due to the long-term environmental adaptability of plant, and the differences of the polysaccharides might influence the stress resistance of L. chinensis.     

Isolation of gentamicin C compounds from culture filtrates of Micromonospora purpurea

A liquid chromatographic method was developed for the isolation of gentamicin C compounds from commercial fermentation products in order to monitor health hazards (oto- and nephrotoxicity). Chromatography was carried out on silica gel 60 (15-40 microns) with a medium-pressure chromatographic system, employing methanol-25% ammonia solution (85:15, v/v) and methanol-chloroform-25% ammonia solution (20:10:5, v/v) as mobile phases. The eluted fractions were neutralized with 1.0 M hydrochloric acid, concentrated in vacuo and desalted by gel filtration. It was possible to demonstrate by 1H NMR spectroscopy and high-performance liquid and thin-layer chromatography that the separated fractions contained components C1, C1a and C2 in purities of more than 95%.     

β,γ-CHF- and β,γ-CHCl-dGTP diastereomers: synthesis, discrete 31P NMR signatures, and absolute configurations of new stereochemical probes for DNA polymerases

Deoxynucleoside 5'-triphosphate analogues in which the β,γ-bridging oxygen has been replaced with a CXY group are useful chemical probes to investigate DNA polymerase catalytic and base-selection mechanisms. A limitation of such probes has been that conventional synthetic methods generate a mixture of diastereomers when the bridging carbon substitution is nonequivalent (X ≠ Y). We report here a general solution to this long-standing problem with four examples of β,γ-CXY dNTP diastereomers: (S)- and (R)-β,γ-CHCl-dGTP (12a-1/12a-2) and (S)- and (R)-β,γ-CHF-dGTP (12b-1/12b-2). Central to their preparation was conversion of the prochiral parent bisphosphonic acids to the P,C-dimorpholinamide derivatives 7 of their (R)-mandelic acid monoesters, which provided access to the individual diastereomers 7a-1, 7a-2, 7b-1, and 7b-2 by preparative HPLC. Selective acidic hydrolysis of the P-N bond then afforded "portal" diastereomers, which were readily coupled to morpholine-activated dGMP. Removal of the chiral auxiliary by H(2) (Pd/C) gave the four individual diastereomeric nucleotides 12, which were characterized by (31)P, (1)H, and (19)F NMR spectroscopy and by mass spectrometry. After treatment with Chelex-100 to remove traces of paramagnetic ions, at pH ~10 the diastereomer pairs 12a,b exhibit discrete P(α) and P(β)(31)P resonances. The more upfield P(α) and more downfield P(β) resonances (and also the more upfield (19)F NMR resonance in 12b) are assigned to the R configuration at the P(β)-CHX-P(γ) carbons on the basis of the absolute configurations of the individual diastereomers as determined from the X-ray crystallographic structures of their ternary complexes with DNA and polymerase β.     

Optimized hydrolysis and analysis of Radix Asparagi polysaccharide monosaccharide composition by capillary zone electrophoresis

Using orthogonal design, optimized conditions for the hydrolysis of the polysaccharide from Radix Asparagi were determined, as well as its monosaccharide composition. Optimized hydrolysis conditions were a temperature of 100°C in 1.5 M sulfuric acid solution for 5 h. The resulting monosaccharides were derivatized with 1‐phenyl‐3‐methyl‐5‐pyrazolone, then separated by capillary zone electrophoresis in 40 mM sodium tetraborate buffer (pH 10.1), and detected by ultraviolet absorption at 245 nm. Results indicate that the polysaccharide from Radix Asparagi is composed of xylose, arabinose, glucose, rhamnose, mannose, galactose, glucuronic acid, and galacturonic acid, which differs from published findings. Moreover, xylose, glucuronic acid, and galacturonic acid have not been previously reported in Radix Asparagi polysaccharide. This method is simple, fast, and yields a highly efficient separation. As well, these findings can be applied to quality control of Radix Asparagi and for in‐depth study of the biological activity of Radix Asparagi polysaccharide.