过硫酸化岩藻多糖硫酸酯

岩藻多糖硫酸酯(fucoidan或fucan sulfate,FS)是一种硫酸多糖,具有多种生物活性。硫酸基团对多糖活性起重要作用,并且多糖活性与硫酸基团含量呈正相关。近些年,国内外研究者对SF进行硫酸化修饰以获得高硫酸基团含量和高活性的过硫酸化岩藻多糖硫酸酯。为促进对FS硫酸化修饰的深入了解,本文对FS活性与硫酸基团含量及位置的关系、过硫酸化方法及过硫酸化岩藻多糖硫酸酯活性的研究进展进行了综述。     

不同硫取代度昆布多糖硫酸酯的合成及理化性质初步研究

目的:对昆布多糖进行不同硫取代度的硫酸酯化修饰,并对其产物的硫酸基含量、糖含量与分子量进行检测,为研究不同硫取代度昆布多糖硫酸酯的生物活性奠定物质基础。方法:采用氯磺酸-吡啶法对昆布多糖进行硫酸化修饰,通过改变硫酸化修饰条件,来制取不同硫酸基取代度的昆布多糖硫酸酯;利用盐酸水解-硫酸钡比浊法测定昆布多糖硫酸酯的硫酸基含量,并通过公式求得其硫取代度;用苯酚-硫酸法测定昆布多糖硫酸酯的多糖含量,并使用HPGPC法测定其分子量。结果:两种不同硫取代度昆布多糖硫酸酯的硫酸基含量分别为37.8%、45.92%,取代度分别为1.07、1.51,糖含量分别为44.52%、37.19%,分子量分别为13000、16000。结论:利用氯磺酸-吡啶法对昆布多糖进行硫酸酯化修饰,该方法可以获取不同取代度产物,酯化率高。     

正交实验法优选香菇多糖的提取工艺及其硫酸酯化研究

目的:考察香菇多糖的提取工艺,制备香菇多糖硫酸酯。方法:采用正交试验法考察加水量、提取时间、提取温度和粒度4个因素对香菇多糖硫酸酯提取率及其中总糖含量的影响,应用硫酸法制备香菇多糖硫酸酯并对得到的成分进行鉴别。结果:通过对正交实验结果的极差分析。得出提取温度和加水量对多糖提取率影响比较著性,提取温度和提取时间对多糖含量的影响比较著性。确定香菇多糖提取的最佳工艺为:应用40倍量的水,每次提取4 h,提取温度90℃,香菇粒度为80目。制备的多糖硫酸酯中硫酸基含量为22.80%,显示了相对较强的生物活性。结论:本实验成功的确定了提取香菇多糖的最佳工艺,制备了硫酸基含量较高的硫酸酯化香菇多糖。     

多糖的化学修饰对其生物活性影响研究进展

多糖是重要的药用活性成分,将其结构进行化学修饰,得到的修饰后多糖有可能具有较修饰前更高的活性或者产生新的活性。本文对这一方面进行研究,阐述了硫酸化、磷酸化、羧甲基化、烷基化、乙酰化等化学修饰方法对多糖生物活性的影响,并对多糖化学修饰应用前景加以展望。     

多糖及其硫酸化衍生物的抗病毒及免疫增强活性研究进展

近年来,人们发现多糖具有广泛的生物活性,并且越来越多的多糖被投入临床应用.其中,增强免疫和抗病毒作用是绝大多数多糖的主要药理作用,是多糖的共性.其中硫酸多糖因其显著的抗病毒和增强免疫活性而具有广阔的应用前景.文章就近年来国内外多糖分类及其硫酸化产物在抗病毒、增强免疫作用进行了综述.     

响应面法优化猴头菌硫酸化多糖

[目的]为了获得猴头菌多糖的最佳硫酸化修饰条件,提高猴头菌硫酸化多糖硫酸基团的取代度。[方法]采用单因素比较氯磺酸-吡啶摩尔比、反应温度和反应时间对猴头菌硫酸化多糖取代度的影响,利用响应面法对各因素的最佳水平以及各因素之间的交互作用进一步研究。[结果]猴头菌多糖的最佳硫酸化修饰条件为:氯磺酸-吡啶摩尔比为1:4、反应温度为59℃、反应时间为2. 6 h,取代度为0. 457,与模型的预测值基本相符。[结论]响应面法优化得到猴头菌多糖的硫酸化修饰条件参数准确,该模型可以用于猴头菌多糖硫酸化修饰条件的优化。     

薤白多糖的硫酸化修饰及体外抗氧化活性

为探讨薤白多糖硫酸化修饰的最佳条件,以及硫酸化修饰提高薤白多糖活性的可能性,采用氯磺酸-吡啶法对醇沉法得到的薤白多糖和柱层析纯化的3种分级薤白多糖进行硫酸化修饰,以氯磺酸-吡啶配比、反应温度和反应时间为自变量,修饰产物的硫酸基取代度(DS)为响应值,应用响应面设计法确定硫酸化修饰的最佳条件,用H2O2/Fe2+体系法和邻苯三酚自氧化法测定修饰产物的抗氧化活性。结果表明:薤白多糖氯磺酸-吡啶法修饰的最佳条件为氯磺酸∶吡啶=1∶3,反应温度65℃,反应时间2 h,此条件下硫酸根取代度为0.470,硫酸化修饰能提高薤白多糖的体外抗氧化活性。     

灰树花子实体多糖D-组分的提取、硫酸化及免疫测定

从灰树花(Maitake)子实体中提取分离得到子实体多糖D组分,并分别考察了提取中的几个关键因素对D组分得率的影响,包括加水倍数、浸提时间、醇沉浓度、浓缩倍数。然后,对D组分进行了硫酸化修饰,得到了两种不同取代度的硫酸化多糖。最后,研究了灰树花多糖D组分及硫酸化灰树花多糖D组分对小鼠的免疫器官重量、腹腔巨噬细胞吞噬功能、血清溶血素形成及淋巴细胞转化率的影响。结果表明,在10mgkg剂量下,灰树花多糖D组分及硫酸化灰树花多糖D组分具有免疫增强作用,并且在合适的取代度下硫酸化灰树花多糖D组分比灰树花多糖D组分表现了更强的免疫调节作用。     

多糖硫酸酯化修饰及其抗凝血作用研究进展

硫酸多糖是一种单糖分子上的一个或多个羟基被硫酸根取代的多糖,近年来由于其良好的抗凝血活性及其较低的副作用被人们所关注.硫酸多糖包括天然硫酸多糖和化学法硫酸化多糖两种,研究证实两者都具有较好的抗凝血活性.对于硫酸多糖的抗凝血活性的构效关系的研究是改进其功能性质的核心,也是国内外研究的热点.本文综述了硫酸多糖的硫酸化方法,硫酸多糖的抗凝血活性以及机理,并对硫酸多糖的研究方向进行了展望.     

灰树花多糖的分子修饰及其活性研究进展

灰树花是一种高蛋白低脂肪的食品,具有免疫调节、抗氧化和抗肿瘤等生物活性。其中,多糖是灰树花的主要活性成分之一。对多糖进行分子修饰是提高它原有的生物活性或增加新活性的重要途径之一。综述了灰树花多糖的分子修饰方法,以及修饰后灰树花多糖的生物活性及其构效关系的研究进展,以期为灰树花多糖的深入研究和开发利用提供参考。     

Chemically Sulfated Polysaccharides from Agaricus blazei Murill: Synthesis,Characterization and Anti-HIV Activity

AIDS, caused by HIV-1, is one of the most dangerous infectious diseases in the world. Therefore, it is necessary to develop new drugs with more potent bioactivities, less toxicity and higher tolerability for controlling the viral load, particularly by using the raw materials that are widely available. Agaricus blazei Murill (AbM), known in China as jisongrong, is of great importance as a food source and as a health-promoting supplement for immunomodulation. The polysaccharides of AbM exhibit various biological activities, such as regulating cellular immunity and providing anti-oxidative, anti-infective, and anti-inflammatory effects. At present, to our knowledge, no report has explored the chemically sulfated and anti-HIV-1 activity of AbM polysaccharides. Herein, the sulfated AbM polysaccharides with different sulfur contents were prepared by the chlorosulfonic acid-pyridine method. The characteristics of sulfated derivatives were established by the determination of the sulfur content, the relative molecular weight, and the Fourier-transform infrared spectroscopy. The anti-HIV activities of the sulfated AbM polysaccharides were evaluated by CCK-8 and the single-cycle pseudovirus infection (TZM-bl) assay. The sulfated AbM polysaccharides had strong antiviral properties, and the half-maximal inhibitory concentrations approached that of the positive control, azidothymidine. Sulfated modification of AbM polysaccharides can increase their anti-HIV pharmacological activity, which makes them promising alternative candidates as bioactive macromolecules for biomedical applications in HIV/AIDS.     

Antiviral Activities of Marine Pseudomonas Polysaccharides and Their Oversulfated Derivatives

A marine Pseudomonas species WAK-1 strain simultaneously produces extracellular glycosaminoglycan and sulfated polysaccharide. Among the antiviral activities tested for these polysaccharides, the latter showed anti-HSV-1 activity in RPMI 8226 cells (50% effective concentration is 1.4 μg/ml). Oversulfated derivatives of these polysaccharides prepared by dicyclohexylcarbodiimide-mediated reaction for both polysaccharides showed antiviral activities against influenza virus type A (for glycosaminoglycan, 50% effective concentration is 11.0 μg/ml; for another, 2.9 μg/ml). Glycosaminoglycan, sulfated polysaccharide, and their chemically synthesized oversulfated derivatives did not show antiviral activities against influenza virus type B and human immunodeficiency virus type 1. No cytotoxicity of these products was noted against host cells at the 50% cytotoxic concentration of 100 μg/ml, except that naturally occurring sulfated polysaccharide had 50% cytotoxicity against MT-4 cells at 8–21 μg/ml. Received May 1, 1998; accepted July 24, 1998.     

功能性低分子量岩藻多糖的研究进展

低分子量岩藻多糖来源于褐藻,是一类含有硫酸基团的多糖,具有多种生物学功能,如抗凝血、抗病毒、抗血栓、抗肿瘤等功能,因此可被广泛地应用于医药、食品等领域。着重介绍了低分子量岩藻多糖的制备及其生物学功能的研究进展。     

Review: Prospects for the Use of Extracts and Polysaccharides from Marine Algae to Prevent and Treat the Diseases Caused by Helicobacter pylori

Helicobacter pylori possesses a broad spectrum of pathogenic factors that allow it to survive and colonize the gastric mucosa, and thus, the pathogenetic targets, which have the same diversity, require search for and the development of alternative, effective, and innocuous means for the eradication of H. pylori. In recent years, fucoidans have been extensively studied due to the numerous interesting biological activities, including the anti‐adhesive, anti‐oxidative, antitoxic, immunomodulatory, anticoagulant, and anti‐infection effects. This review summarizes the data on the effects of extracts and sulfated polysaccharides of marine algae, mainly fucoidans, on pathogenic targets in Helicobacter infection. The pathogenetic targets for therapeutic agents after H. pylori infection, such as flagellas, urease, and other enzymes, including adhesins, cytotoxin A (VacA), phospholipase, and L‐8, are characterized here. The main target for the sulfated polysaccharides of seaweed is cell receptors of the gastric mucosa. This review presents the published data about the pleiotropic anti‐inflammatory effects of polysaccharides on the gastric mucosa. It is known that fucoidan and other sulfated polysaccharides from algae have anti‐ulcer effects, prevent the adhesion of H. pylori to, and reduce the formation of biofilm. The authors speculate that the effect of sulfated polysaccharides on the infectious process caused by H. pylori is related to their action on innate and adaptive immunity cells, and also anti‐oxidant and antitoxic potential. Presented in the review are materials indicated for the study of extracts and sulfated polysaccharides from seaweed during H. pylori infection, as these compounds are characterized by multimodality actions. Based on the analysis of literary materials in recent years, the authors concluded that fucoidan can be attributed to the generation of new candidates to create drugs intended for the inclusion in the scheme of eradication therapy of H. pylori infection.     

植物多糖对巨噬细胞的免疫调节作用

植物多糖是一类广泛存在于植物中具有多种生物学活性的天然大分子物质,对免疫系统的影响普遍认为是通过对天然免疫系统的调节作用,尤其是对巨噬细胞免疫功能的影响. 许多研究表明,植物多糖与巨噬细胞表面多种受体结合启动不同信号途径而发挥生物学作用.本文综述了来源于不同种属的多种植物多糖对巨噬细胞释放活性氧、分泌细胞因子和趋化因子等的免疫调节作用,为新型免疫调节药物的研究开发提供了新的思路.     

食用蕈菌硒多糖研究进展

食用蕈菌硒多糖是无机硒与蕈菌多糖结合而成的有机硒化合物,兼有二者的活性。该文综述了食用蕈菌硒多糖的组成分析、提取、分离纯化以及生理功能、应用现状等方面的研究进展。     

Effect of Sulfated Modification on the Molecular Characteristics and Biological Activities of Polysaccharides from Hypsizigus marmoreus

The effect of sulfated modification on polysaccharides from Hypsizigus marmoreus was examined by determining their molecular structures and bioactivities. The sulfation, which was implemented by using an orthogonal array design, produced polysaccharides with varying degrees of substitution (DS) ranging from 0.11 to 1.06. The sulfated polysaccharides exhibited a lower average molecular weight (M _w) and considerably higher radius of gyration (R _g) than those of native polysaccharide, suggesting that the conformation of the sulfated polysaccharides had been changed towards a more extended type. The inhibitory activity toward cancer cell growth was enhanced by treating with the sulfated polysaccharides by up to 34%, as compared to the native polysaccharide. In addition, treating with the sulfated polysaccharides increased the nitric oxide (NO) and cytokine (IL-1β and TNF-α) release to levels comparable to those detected in the positive control, lipopolysaccharide (LPS), suggesting that the sulfated polysaccharides might have strong immunomodulatory activity.     

A 2-sulfated, 3-linked alpha-L-galactan is an anticoagulant polysaccharide

Marine alga is an abundant source of sulfated polysaccharides with potent anticoagulant activity. However, several attempts to identify the specific structural features in these compounds, which confer the biological activity, failed due to their complex, heterogeneous structure. We isolated and characterized several sulfated alpha-L-galactans and sulfated alpha-L-fucans from marine invertebrates. In contrast to the algal fucans and galactans, these invertebrate polysaccharides have a simple structure, composed of well-defined units of oligosaccharides. We employed two of these compounds to elucidate their structure-anticoagulant action relationship. Our results indicate that a 2-sulfated, 3-linked alpha-L-galactan, but not an alpha-L-fucan, is a potent thrombin inhibitor mediated by antithrombin or heparin cofactor II. The difference between the activities of these two polysaccharides is not very pronounced when factor Xa replaces thrombin. Thus, the anticoagulant activity of sulfated galactan and sulfated fucan is not merely a consequence of their charge density. The interaction of these polysaccharides with coagulation cofactors and their target proteases are specific. Identification of specific structural requirements in sulfated galactans and sulfated fucans necessary for interaction with coagulation cofactors is an essential step for a more rational approach to develop new anticoagulant and antithrombotic drugs.