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从虎奶菇菌核中提取出一种水溶性高支化葡聚糖,并用氯磺酸和吡啶在无水二甲亚砜中进行硫酸酯衍生化,制备出硫酸酯衍生物.用巴比赛小鼠动物实验研究该多糖及其硫酸酯衍生物的体内抗肉瘤S-180活性,以及用肝癌细胞株HepG2研究体外活性,同时讨论多糖分子尺寸与抗癌活性的关系.通过形态学、组织切片、以及酶联免疫法研究硫酸酯化对多糖抗肿瘤活性的影响.结果表明,支链多糖的均方根旋转半径在42.5~113 nm之间,显示出较高的体内和体外抗肿瘤活性,硫酸酯衍生物的均方根旋转半径在17.8~34.9 nm之间,抗癌活性随其分子尺寸的增大而逐渐提高.多糖及其硫酸酯衍生物能诱导人体肝癌HepG2细胞凋亡,且具有时间依赖性.它们对免疫反应的调节作用可通过肿瘤坏死因子TNF-α来介导. 相似文献
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黑木耳酸性杂多糖的超声波辐射降解 总被引:3,自引:0,他引:3
黑木耳酸性杂多糖的超声波辐射降解李翔,张俐娜(武汉大学化学系武汉430072)关键词黑木耳多糖,超声波辐射,特性粘数,糖醛酸含量,凝胶渗透色谱黑木耳多糖具有抗肿瘤,抗炎症,抗凝血及免疫功能[1~5],黑木耳子实体含两种酸性杂多糖和3种有不同支链和相对... 相似文献
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海洋硫酸多糖911的荧光标记研究 总被引:7,自引:0,他引:7
硫酸多糖(911)的性末端的半缩醛基,通过还原胺化反应与酪胺(Tyr)的氨基共价偶联,911-Tyr中酪胺引入的仲氨基通过与异硫氰酸酯荧光素(FITC)进行亲核反应,实现对911还原末端的选择性荧光标记。用UV-Vis吸收光谱,^1H NMR和HPSEC对偶联与标记结果进行确证,从^1H NMR谱推测911与酪胺的偶联率及FITC为911-Tyr标记率分别为60%和80%。由于采用的是911末端选择性标记,对911的抗凝活性无明显影响,也无明显细胞的毒性。以荧光标记的911作为探针,对淋巴细胞有较强的选择性标记染色。该法适用于具有还原末端的多糖及寡糖的荧光标记。 相似文献
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6-氨基-3-取代吲哚的合成和生物活性研究 总被引:1,自引:0,他引:1
6-氨基-3-取代吲哚及其衍生物是一种重要的医药和有机化工中间体,不仅能合成一些具有生理活性和药理活性的化合物,如:合成一些具有药物活性的色胺类化合物及其衍生物[1,2];合成一些植物生长调节剂,如吲哚-3-乙腈和吲哚-3-乙酸类化合物[3];合成一些具有生物活性的天然化合物Drag 相似文献
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单乙酰二茂铁Shiff碱(单-m-氨基)卟啉及汞配合物合成樊耀亭吕秉玲(郑州大学化学系450052)(大连理工大学化工院院116012)二茂铁及其衍生物具有强的生物活性,是许多酶催化反应的抑制剂,而卟啉及其金属配合物与生命物质密切相关,新近已用于传能... 相似文献
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为研究关白附多糖及其硫酸酯的经典途径抗补体活性, 以关白附[Aconitum coreanum(Lévl.) Raipaics]为原料, 经水提醇沉、 DE-32、 Superdex-200和Superdex-75凝胶柱分离纯化, 得到1个均一的中性多糖KMPS-2A. 采用高效凝胶渗透色谱法、 甲基化、 核磁共振和红外光谱等手段对KMPS-2A的结构进行了鉴定; 采用氯磺酸吡啶法制备了多糖硫酸酯, 并测定了多糖及硫酸酯的抗补体活性. 结果表明, KMPS-2A的平均相对分子量为6.76×105, 结构为α-1,6-D-Glc链接的线性多糖; 在氯磺酸与吡啶的体积比为1.75∶1.0时制备的多糖硫酸酯1.75B的取代度最高为1.79. 碳核磁谱分析结果表明, 硫酸基团先后取代C2, C3及C4位. 该多糖硫酸酯的抗补体活性与其硫酸基团取代度呈现一定的相关性, 多糖硫酸酯1.75B的经典途径抗补体活性优于阳性对照药肝素, 表明其具有开发成为补体抑制剂的潜力. 相似文献
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黑木耳酸性杂多糖构效关系的研究 总被引:5,自引:0,他引:5
研究了不同分子量的黑木耳酸性杂多糖6个分级和未分级试样的生物活性,小鼠腹腔注射试验结果表明该多糖具有促进白细胞增加、抗凝血和降低血小板的作用,其活性随着多糖分子量和糖醛酸含量降低而增大,即生物活性依赖于多糖在水中的溶解度,用酸碱返滴定法测定多糖中糖醛酸含量。实验结果与文献值一致。 相似文献
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Tomoyuki Miyazawa Haruka Abe Takayuki Suzuki Yosuke Togashi Kazuhiro Koshiji Yuki Nonaka 《Journal of carbohydrate chemistry》2013,32(5):252-266
We evaluated the potential of a linear β-1,3-glucan (curdlan) as a starting material to access C6-modified glucose derivatives and found that 6-bromo-6-deoxyglucose, 6-azide-6-deoxyglucose, and 6-acetamido-6-deoxyglucose could be readily prepared from curdlan through its C6-selective and quantitative modifications and subsequent acid-catalyzed hydrolysis. 相似文献
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Tegshi Muschin Shuqin Han Taisei Kanamoto Hideki Nakashima Takashi Yoshida 《Journal of polymer science. Part A, Polymer chemistry》2011,49(15):3241-3247
To develop a biomaterial with an influenza virus‐adsorptive functionality, an alkyl curdlan sulfate was prepared by ionic interaction between a positively charged didodecyldimethyl ammonium bromide and a negatively charged sulfate group of curdlan sulfate, which has potent anti‐HIV activity, and then it was coated on a membrane filter with a 1‐μm pore size by hydrophobic interaction with the long alkyl groups in the curdlan sulfate. The alkyl curdlan sulfate with the degree of alkylation (DOA) of 0.03 (one didodecyldimethyl group/12 sugar residues with 36 hydroxyl or sulfate groups) showed potent anti‐HIV activity in a 50% effective concentration (EC50) as low as 0.87 μg/mL (standard curdlan sulfate EC50 = 0.3 μg/mL), and the activity decreased with increasing DOA. A DOA higher than 0.1 (one didodecyldimethyl group/three sugar residues with nine hydroxyl or sulfate groups) gave no anti‐HIV activity. Although both curdlan sulfate and alkyl curdlan sulfates did not inhibited infection of Madin‐Darby canine kidney cells by influenza viruses, the alkyl curdlan sulfate‐coated membrane filter was found to have a specific adsorptive functionality for influenza A virus in vitro. When 1.6 mg of the alkyl curdlan sulfate with the DOA of 0.03 was coated on a membrane filter (φ13 mm; pore size, 1 μm), three stacked alkyl curdlan sulfate‐coated membrane filters dramatically decreased hemagglutination to 1/4–1/32. However, the membrane filter did not effectively remove on influenza B viruses, and thus a membrane filter without alkyl curdlan sulfate was not effective against influenza viruses. These results can therefore be presumed to demonstrate that the alkyl curdlan sulfate‐coated membrane filter removed influenza A viruses by adsorption between the negatively charged sulfate groups and the positively charged envelope protein of the virus. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
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Yang Jin Hongbin Zhang Yimei Yin Katsuyoshi Nishinari 《Colloid and polymer science》2006,284(12):1371-1377
Tapping mode atomic force microscopy was used to study the bacterial polysaccharide curdlan deposited from dimethyl sulfoxide (Me2SO) and NaOH aqueous solutions. For curdlan in Me2SO, flexible single chains corresponding to a disordered conformation were observed at a concentration of 5 mg/l, and the chain diameter was measured to be 0.65±0.05 nm, which showed good agreement with the expected value of the single polysaccharide chain. Because the concentration of curdlan increased, the chains became more rigid and aggregated, subsequently, the network structures of curdlan appeared. However, curdlan samples deposited from a 5 mM NaOH solution showed entirely different conformations. The chains observed were almost in the form of micelles of several nanometers, which were supermolecular assemblies. The heterogeneously dense zones were observed as the curdlan concentration increased to 40 mg/l. When the concentration of curdlan was above 100 mg/l, which might cause the real concentration of curdlan on the mica substrate after drying treatment exceeding some critical value of gelation, gel network structures were formed. Keeping on increasing the concentration of curdlan, the image showed a more homogeneous fibrous network. 相似文献
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《Polymer Gels and Networks》1997,5(3):241-250
Gelation occurred at a concentration of 0.3% curdlan solution at room temperature (25 °C). The curdlan showed a Newtonian behavior at 0.1%, but plastic behavior above 0.2% even at a temperature of 38 °C. The dynamic modulus remained at a constant value with an increase of temperature up to 40 °C., which was estimated to be a transition temperature, then it decreased rapidly with an increase of temperature until 55 °C; however, it increased gradually with a further increase of temperature. The dynamic viscoelasticity of curdlan solution remained at very low values on addition of urea (4 M) and decreased with increasing temperature. The optical rotation of curdlan (0.1%) increased with a decrease of temperature.Possible modes of intra- and intermolecular hydrogen bonding within and between curdlan molecules were proposed. A hydrophobic interaction might take place at high temperatures (>55 °C), the mode of which was also proposed. 相似文献
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Numata M Koumoto K Mizu M Sakurai K Shinkai S 《Organic & biomolecular chemistry》2005,3(12):2255-2261
We already found that beta-1,3-glucan polysaccharides form polymeric complexes with certain polynucleotides, but the parallel vs. anti-parallel orientation in those complexes had remained unsolved. In this paper, this controversial problem has been discussed for curdlan/oligo(dA) complexes utilizing two different energy transfer techniques. The first system consists of a combination of fluorescein-labeled curdlan and 3'-(or 5'-)tetramethyl-rhodamine (TAMRA)-labeled oligo(dA). The second system utilizes gold nanoparticles: that is, two curdlan chains were linked by a disulfide bond and after complexation with oligo(dA), the complex was immobilized on gold nanoparticles. In this system, TAMRA was attached to the 3'(or 5') end of oligo(dA) and the gold particle acted as a fluorescence quencher (energy acceptor). These experiments have led us to conclude that in the curdlan/oligo(dA) complex, parallel orientation is more favourable than anti-parallel orientation. These findings have enabled us to envision a clearer image for the complexation mode between beta-1,3-glucan polysaccharides and polynucleotides. 相似文献
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Fermentative production of curdlan 总被引:1,自引:0,他引:1
Curdlan was produced by pure culture fermentation using Agrobacterium radiobacter NCIM 2443. Three different carbon sources (glucose, sucrose, maltose) were selected for study. Sucrose was found to be the most efficient. Utilization of sugar during the course of fermentation was studied, and the data were correlated to the production of curdlan. Curdlan mimics a secondary metabolite, in that its synthesis is associated with the poststationary growth phase of nitrogen-depleted batch culture. This was inferred from the results obtained from utilization of nitrogen. Regulation of pH at 6.1 +/- 0.3 resulted in an increased yield of curdlan from 2.48 to 4.8 g/L, and the corresponding increase in succinoglucan production was from 1.78 to 2.8 g/L. An attempt was made to increase curdlan production by the addition of the uridine nucleotides UMP and UDP-glucose to the fermentation broth. It was found that UDP-glucose at 0.8 microg/mL and UMP at 0.6 microg/mL served as precursors for curdlan and succinoglucan production when added after 18 h of nitrogen depletion in the fermentation broth. 相似文献
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不同分子量可德胶水悬浮液的粘弹性研究 总被引:2,自引:0,他引:2
采用动态粘弹性测量研究了不同分子量的生物大分子可德胶 (Curdlan)水悬浮液 (ASC)的流变学特性 .室温下观察到ASC具有弹性 (Solid like)行为 ,储能模量G′在测量范围内轻微依赖频率 ,而损耗模量G″和损耗角正切tanδ存在最小值 .ASC粘弹性随可德胶分子量和浓度的增加而增强 .ASC的流动特性符合Herschel Bulkley模型 ;其弹性行为可以通过渗流理论的标度弹性模型来描述 .网络结构是由于可德胶颗粒聚集或絮凝而形成的 ,当可德胶含量超过临界浓度cs=0 3 %时 ,弹性模量G′与可德胶浓度存在标度关系G′=Goεt,其中标度指数t=2 5 4. 相似文献
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Hidehisa Kawashima Itsuki Ozawa Masashi Kijima 《Journal of polymer science. Part A, Polymer chemistry》2020,58(13):1747-1756
Rigid and little moldable curdlan, a linear β-1,3-glucan having intra- and interchain hydrogen bonds, was reacted with several alkyl isocyanates, which gave thermoplastic curdlan alkyl carbamates (CrdC) with degree of substitution about 2. The alkyl carbamation at hydroxy groups in the glucan skeleton effectively broke the interchain hydrogen bonds of curdlan and increased flexibility of CrdC, while the newly formed carbamate moieties could moderately keep the hydrogen bonding ability in CrdC. Elongating the alkyl groups in the carbamate side chains increased solubility in organic solvents and thermoplasticity of CrdC, which enabled to make homogeneous and free-standing films by both methods of solution-casting and hot-pressing. 相似文献
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Jeongyun Heo Thomas A. Sobiech Hilliard L. Kutscher Lee Chaves Dinesh K. Sukumaran Shanta Karki Admire Dube Paras N. Prasad Jessica L. Reynolds 《Macromolecular bioscience》2021,21(1)
A nanoformulation composed of curdlan, a linear polysaccharide of 1,3‐β‐linked d ‐glucose units, hydrogen bonded to poly(γ ‐glutamic acid) (PGA), was developed to stimulate macrophage. Curdlan/PGA nanoparticles (C‐NP) are formulated by physically blending curdlan (0.2 mg mL?1 in 0.4 m NaOH) with PGA (0.8 mg mL?1). Forster resonance energy transfer (FRET) analysis demonstrates a heterospecies interpolymer complex formed between curdlan and PGA. The 1H‐NMR spectra display significant peak broadening as well as downfield chemical shifts of the hydroxyl proton resonances of curdlan, indicating potential intermolecular hydrogen bonding interactions. In addition, the cross peaks in 1H‐1H 2D‐NOESY suggest intermolecular associations between the OH‐2/OH‐4 hydroxyl groups of curdlan and the carboxylic‐/amide‐groups of PGA via hydrogen bonding. Intracellular uptake of C‐NP occurs over time in human monocyte‐derived macrophage (MDM). Furthermore, C‐NP nanoparticles dose‐dependently increase gene expression for TNF‐α, IL‐6, and IL‐8 at 24 h in MDM. C‐NP nanoparticles also stimulate the release of IL‐lβ, MCP‐1, TNF‐α, IL‐8, IL‐12p70, IL‐17, IL‐18, and IL‐23 from MDM. Overall, this is the first demonstration of a simplistic nanoformulation formed by hydrogen bonding between curdlan and PGA that modulates cytokine gene expression and release of cytokines from MDM. 相似文献