野生和人工栽培漆树液多糖的分子结构与生物活性

从湖北毛坝野生(大木)和人工栽培(小木)漆树液中分离纯化出酸性杂多糖D-LP和X-LP,化学降解和光谱分析表明两种多糖均含有D-Gal、D-GlcA、L-Ara和L-Rha,其摩尔比分别为77:18.3:3.7:1和63.7:13.3:3.9:1.两种漆多糖都是以β(1→3)D-Gal为主链的高度支化酸性杂多糖.D-LP支化度较高,分支点在Gal的C₆和C₄位;而X-LP仅有部分主链D-Gal的C₆位发生支化.小鼠腹腔注射试验表明,两种漆多糖均具有明显的免疫抑制作用,同时由野生漆树液提取的D-LP显示出比X-LP更高的免疫抑制功能和升白细胞活性功能.     

木蹄多糖提取工艺研究

通过对木蹄多糖提取得率有影响的子实体粉末颗粒大小、料水比、提取温度和提取时间进行的单因素研究,其中对料水比、提取温度和提取时间3个因素采用应用响应面法进行了优化,确定了木蹄子实体多糖的最佳提取工艺条件：子实体粉末颗粒60目,料水比1：42．92,提取温度88．92℃,提取时间3．92h,多糖得率达到5．68％。     

百合皂甙多糖的连续提取工艺研究

皂甙和多糖是药用百合的两个主要有效成份。文章用正交实验法对百合皂甙多糖的提取工艺进行了研究。优选出简便可靠且适合工业化生产的连续提取百合皂甙多糖的工艺。百合皂甙的最佳提取工艺条件是:温度为70℃,乙醇浓度为80%,固液比例为1:6,提取时间3h,提取次数3次。多糖的最佳提取工艺条件是:温度为95℃,固液比例为1:10,提取时间3h,提取次数2次。用AB-8大孔吸附树脂分离、乙醚-丙酮分步沉淀得到纯百合皂甙。     

Optimization of the Hydrolysis of Freshwater Polysaccharides

Abstract

Three techniques of acid hydrolysis are verified for their ability to efficiently hydrolyse freshwater polysaccharides. Polysaccharides isolated from two eutrophic lakes were hydrolysed rapidly as compared to model or marine polysaccharides. No single technique is 100% satisfactory for all polysaccharides (i.e. complete hydrolysis with no degradation). Hydrolysis by 0.1 M HCl appeared to give the best results while acceptable results were also obtained for 1.2 M H₂SO₄. The results suggest that it is prudent to hydrolyse freshwater polysaccharides under the least drastic conditions and for as short of a time as possible in order to minimize decomposition of the sample, (esp. uronic acids). Interferences due to humic acid; did not appear to increase as a function of hydrolysis time.     

百合多糖的超声波提取工艺研究

以百合多糖的得率为指标,对超声波提取与沸水回流提取进行了比较。采用单因素试验和正交试验对超声波提取百合多糖工艺进行优选。实验表明,超声波提取百合多糖的最佳工艺条件为:提取温度90℃,料液比1∶6,提取3次,提取时间40 min,百合多糖的得率为1.37%。     

Central Composite Design for Optimized Extraction of Polysaccharides from Undaria pinnatifida

Response surface methodology was used to optimize the extraction conditions of polysaccharides from Undaria pinnatifida. The effects of three independent variables, extraction time, extraction temperature and ratio of water to raw material were investigated by a central composite design. The experimental data were fitted to a second-order polynomial equation via multiple regression analysis and also examined with the appropriate statistical methods. The adjusted coefficient of determination(R_ADj²) for the model was 0.9171. An optimum extraction yield of 30.78% was obtained when the extraction temperature was 95℃, extraction time was 4.5 h, and the ratio of water to raw material was 35(mL/g). Under these conditions, validation experiments were done and the mean extraction yield of polysaccharides was 30.79%, which was in good agreement with the predicted model value.     

Vacuum Ultraviolet Action Spectroscopy of Polysaccharides

We studied the optical properties of gas-phase polysaccharides (maltose, maltotetraose, and maltohexaose) ions by action spectroscopy using the coupling between a quadrupole ion trap and a vacuum ultraviolet (VUV) beamline at the SOLEIL synchrotron radiation facility (France) in the 7 to 18 eV range. The spectra provide unique benchmarks for evaluation of theoretical data on electronic transitions of model carbohydrates in the VUV range. The effects of the nature of the charge held by polysaccharide ions on the relaxation processes were also explored. Finally the effect of isomerization of polysaccharides (with melezitose and raffinose) on their photofragmentation with VUV photons is presented.

山药多糖的制备及其体外抗氧化活性

提取山药粗多糖并进行精制,分析了山药多糖的单糖组成,并研究了山药多糖的体外抗氧化活性.结果表明,山药精制多糖纯度较高,由鼠李糖、阿拉伯糖、甘露糖、葡萄糖和半乳糖组成.体外抗氧化活性测试结果表明,山药多糖具有一定的还原能力,对羟自由基具有较强的清除能力,并对小鼠肝匀浆自氧化有明显的抑制作用.因此,山药多糖具有较好的抗氧化活性,可作为潜在的抗氧化剂或抗衰老药物进行深入研究和开发.     

碱溶性茶多糖的提取及其分析

在煎煮后的低档绿茶茶渣中提取碱溶性茶多糖,经HPGPC-ELSD法分析其含有3种均一性多糖组分,依出峰顺序其质量分数约为5.96%、78.99%和15.05%;GC-MS法测得组成碱溶性茶多糖的6种单糖:鼠李糖、阿拉伯糖、木糖、甘露糖、葡萄糖和半乳糖,并分析了其摩尔比例.紫外-可见吸收光谱分析显示,碱溶性茶多糖在250～290 nm区段有"波浪状"吸收.红外光谱表征了碱溶性茶多糖的特征,圆二色谱分析了其水溶液的cotton效应.结果表明,在190 nm有正cotton效应,在203 nm有负cotton效应.     

海藻多糖的组成及结构光谱分析

海藻多糖具有抗凝血等多种生物活性,其活性与多糖的组成结构有关。本文对近年来红藻、褐藻及少量绿藻多糖的单糖组成及含量研究以及FT-IR和12^C NMR两种主要光谱手段对多糖结构研究的结果进行了介绍。     

A novel and rapid HPGPC-based strategy for quality control of saccharide-dominant herbal materials: Dendrobium officinale,a case study

Qualitative and quantitative characterization of natural saccharides, especially polysaccharides, in herb materials remains a challenge due to their complicated structures and high macromolecular masses. Currently available methods involve time-consuming and complicated operations, and present poor specificity. Here, a novel and rapid high-performance gel permeation chromatography (HPGPC)-based approach is described for quality assessment of saccharide-dominant herbal materials by simultaneous qualitative and quantitative analysis of saccharide components. Dendrobium officinale, one of the rarest tonic herbs worldwide, was employed as the model herb in this study. First, a HPGPC fingerprint based on the molecular weight distribution of its carbohydrate components was established for qualitative identification of D. officinale. Then, HPGPC-guided dominant holistic polysaccharide marker was separated using ultra-filtration followed by HPGPC determination for quantitative evaluation of D. officinale. The experimental results suggest that this method is more efficient, stable, and convenient compared with the currently available methods for authentication and quality evaluation of D. officinale, and we expect the method will have similar advantages when used for quality control of other saccharide-dominant herbal materials and products. Graphical Abstract

The characteristic HPGPC fingerprint of Dendrobium officinale compared with other confused Dendrobium species     

Sorption of Anionic Polysaccharides and Bovine Serum Albumin on a Macroporous Glass

Concentration and time dependences of the sorption of alginic acid and -carrageenan on an MPS-1000 macroporous glass were studied. The character of pH effect on the sorption of these polysaccharides was established. For a number of sorbents prepared by the preliminary adsorption of polysaccharides on an MPS-1000 glass, the dependence of the sorption of bovine serum albumin (BSA) on the surface content of alginic acid and -carrageenan was studied. The model of adsorption in the silica–polysaccharide–protein system accounting for the interaction between polysaccharide ionic groups and active sites at the sorbent surface and protein molecules was proposed. Acid-base properties of silica modified with polysaccharides were investigated by the potentiometric titration, and the results supporting the validity of the proposed model were obtained.     

多糖类大分子与表面活性剂相互作用的研究进展

多糖类大分子具有天然、无毒、使用安全和可再生及来源丰富等优点. 将多糖类大分子与表面活性剂复配使用, 不仅可利用各自的优势和特性, 而且能发挥二者的协同作用, 大大改善二者的性能. 由于两者之间存在诸如静电作用、疏水作用、偶极相互作用、氢键作用、空间位阻效应等, 水体系中表面活性剂在多糖分子链上的缔合得到调控, 并引起表面活性剂的临界聚集浓度(cac)、临界胶束浓度(cmc)、结合量, 以及体系的表面吸附、界面流变性等呈现各种变化. 本文简要总结了近年来多糖类大分子与表面活性剂复配体系研究方面取得的一些进展, 述及复配体系研究中所采用的方法与手段, 主要讨论复配体系的物理化学性质以及多糖类大分子与表面活性剂相互作用的机制.     

An Exploration of Seaweed Polysaccharides Stimulating Denitrifying Bacteria for Safer Nitrate Removal

Excessive use of nitrogen fertilizer in intensively managed agriculture has resulted in abundant accumulation of nitrate in soil, which limits agriculture sustainability. How to reduce nitrate content is the key to alleviate secondary soil salinization. However, the microorganisms used in soil remediation cause some problems such as weak efficiency and short survival time. In this study, seaweed polysaccharides were used as stimulant to promote the rapid growth and safer nitrate removal of denitrifying bacteria. Firstly, the growth rate and NO₃⁻-N removal capacity of three kinds of denitrifying bacteria, Bacillus subtilis (BS), Pseudomonas stutzeri (PS) and Pseudomonas putida (PP), were compared. The results showed that Bacillus subtilis (BS) had a faster growth rate and stronger nitrate removal ability. We then studied the effects of Enteromorpha linza polysaccharides (EP), carrageenan (CA), and sodium alginate (AL) on growth and denitrification performance of Bacillus subtilis (BS). The results showed that seaweed polysaccharides obviously promoted the growth of Bacillus subtilis (BS), and accelerated the reduction of NO₃⁻-N. More importantly, the increased NH₄⁺-N content could avoid excessive loss of nitrogen, and less NO₂⁻-N accumulation could avoid toxic effects on plants. This new strategy of using denitrifying bacteria for safely remediating secondary soil salinization has a great significance.     

Tailormade Polysaccharides with Defined Branching Patterns: Enzymatic Polymerization of Arabinoxylan Oligosaccharides

The heterogeneous nature of non‐cellulosic polysaccharides, such as arabinoxylan, makes it difficult to correlate molecular structure with macroscopic properties. To study the impact of specific structural features of the polysaccharides on crystallinity or affinity to other cell wall components, collections of polysaccharides with defined repeating units are required. Herein, a chemoenzymatic approach to artificial arabinoxylan polysaccharides with systematically altered branching patterns is described. The polysaccharides were obtained by glycosynthase‐catalyzed polymerization of glycosyl fluorides derived from arabinoxylan oligosaccharides. X‐ray diffraction and adsorption experiments on cellulosic surfaces revealed that the physicochemical properties of the synthetic polysaccharides strongly depend on the specific nature of their substitution patterns. The artificial polysaccharides allow structure–property relationship studies that are not accessible by other means.     

实时直接分析质谱分析中草药多糖

建立了一种机械力化学提取法和实时直接分析质谱(DART-MS)分析相结合的中草药多糖分析方法,同时测定了黄芪、银耳、百合、茯苓、鼓槌石斛、金钗石斛、铁皮石斛和党参8种中草药多糖。比较了机械力化学提取(MCE)法与传统方法的提取效果,并优化了MCE法的提取参数。通过体积排阻色谱分离中草药多糖,建立分子质量校准曲线,估算了多糖分子质量。利用DART-MS直接裂解多糖大分子,可瞬时获得m/z<350的碎片离子,不同的中草药多糖得到的特征性的质谱离子峰可用于多糖样品的有效区分。该方法具有简单、快速、高通量、无需预消化的特点,是直接从复杂多糖大分子中获取特征指纹图谱的有力工具。     

Stability of W/O Emulsions Encapsulating Polysaccharides

In the frame of formulation of W/O emulsions entrapping polysaccharides devoted to agricultural applications, the aim of this work was to study the stability over time of these emulsions, stabilized with either soybean lecithin or polyglycerol polyricinoleate (PGPR) as emulsifiers. Emulsifiers were dissolved in oil phase, and polysaccharides (carboxymethycellulose (CMC), guar, xanthan) in ultrapure water. Emulsions stability was studied through natural aging tests and accelerated aging tests, using bottle tests, microscopy and calorimetry. Experiments showed that PGPR was more efficient than lecithin to stabilize emulsions containing the polysaccharides studied, and that emulsions prepared with CMC showed the best stability.     

Polysaccharides ofAconitum zaravschanicum

The dynamics of the accumulation of water-soluble polysaccharides and pectin substances of Aconitum zaravschanicum Steinb over the vegetation periods have been studied. The maximum amounts of polysaccharides have been established and their comparative physicohemical characteristics have been determined. Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbekistan Republic, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 357–359, May–June, 1993.     

多糖类药物的毛细管电泳分析方法及其应用

从迁移、检测和应用3方面综述了多糖药物毛细管电泳在近20年来的研究进展。     

淫羊藿多糖的分子特征及免疫活性研究

用超声复合酶提取、离子交换凝胶分离、分子筛凝胶纯化得到3个淫羊藿叶多糖组分(EPs-1,EPs-2和EPs-3).3个多糖组分的分子特征通过气相色谱、高效凝胶渗透色谱进行了表征,并采用体外淋巴细胞增殖和巨噬细胞吞噬活性实验对多糖的免疫活性进行了评价.3个多糖组分EPs-1,EPs-2和EPs-3的总糖含量分别为90.36%,94.51%和89.19%.EPs-1,EPs-2和EPs-3主要由半乳糖醛酸(GalA)、半乳糖(Gal)、鼠李糖(Rha)、木糖(Xyl)、阿拉伯糖(Ara)和甘露糖(Man)组成,其平均相对分子质量分别为81.64×10~3,60.53×10~3,21.85×103;3个多糖都能够促进脾淋巴细胞增殖和激活巨噬细胞活性.这些结果说明淫羊藿多糖可以作为天然的免疫活性调节剂应用于医药和功能食品.