共查询到17条相似文献,搜索用时 140 毫秒
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本研究以济源冬凌草多糖为原料,选用化学合成方法对多糖进行结构修饰。采用UV、FT-IR、SEM、TGA、HPLC等方法对冬凌草多糖以及硒多糖结构特征进行了表征;通过DPPH(1,1-二苯基-2-三硝基苯肼)自由基法、羟自由基法等4种方法对其抗氧化活性进行了探究。结果:制备的硒多糖中硒质量分数为1.35 mg/g。硒化修饰后,冬凌草多糖的基本骨架得到保留,单糖种类未发生改变,但其分解温度降低、稳定性下降,多糖形貌也发生明显变化,球状与条状形貌增多,片状形貌减少。此外,在体外抗氧化性实验中,当硒多糖质量浓度为1.6mg/mL时,对DPPH自由基、ABTS自由基、羟自由基清除率分别为68.68%、86.69%、45.12%,均强于冬凌草多糖。 相似文献
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冬凌草硒多糖的制备及其抗氧化活性分析 总被引:1,自引:0,他引:1
以济源冬凌草为原料,水提得到冬凌草多糖,对多糖进行结构修饰制得冬凌草硒多糖.采用UV、FTIR、SEM、TGA、HPLC对冬凌草多糖以及硒多糖结构进行表征;通过1,1-二苯基-2-三硝基苯肼(DPPH)自由基法、2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐(ABTS)自由基法、羟基自由基法以及还原能力测定4种方法对冬凌草多糖及其硒多糖的抗氧化活性进行探究.结果表明,冬凌草硒多糖中硒含量为1.35 mg/g.硒化修饰后,冬凌草多糖的基本骨架得到保留,单糖种类未发生改变,但分解温度降低、稳定性下降,多糖形貌也发生明显变化,球状与条状形貌增多,片状形貌减少.在体外抗氧化性实验中,当冬凌草硒多糖质量浓度为1.6 g/L时,对DPPH自由基、ABTS自由基、羟基自由基清除率分别为68.69%、86.90%、45.12%,均强于冬凌草多糖. 相似文献
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许多有机硒化合物具有生理活性,在医药和添加剂等方面显现出巨大的应用前景。有机硒化合物按照结构可以分为:硒化氨基酸,硒化多糖,肌醇硒酸酯,硒化茶多酚,硒化亚油酸等几大类。本文综述了以上各类有机硒化合物的合成方法。 相似文献
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多糖微量元素络合物作为一类优质的有机微量元素, 因其不仅能发挥多糖的优异生物学功能,而且能显著提高微量元素利用率,减少环境污染等,备受国内外研究者关注。综述了植物、藻类和微生物多糖与硒、锌、铁等微量元素络合物的最新研究进展,强调了多糖分子结构对络合工艺条件的影响及多糖微量元素络合物在饲料工业的应用潜力,并讨论其当前面临的技术难题和解决方案,旨在从生化工程的角度为多糖微量元素络合物的生产提供指导,促进绿色农业种植与绿色畜牧养殖的融合发展。 相似文献
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药用植物内生真菌多糖研究进展 总被引:1,自引:0,他引:1
真菌多糖具有多种生理活性,广泛应用于医药、农业、食品等行业。基于植物内生真菌生长过程中会产生与宿主相同或相似的生理活性成分,药用植物生理活性的多样性赋予了其内生真菌活性的多样性,药用植物内生真菌是开发新型天然活性多糖的资源宝库。综述了近些年来关于药用植物内生真菌作为诱导子调节植物生长、代谢及其体外抗氧化、抗肿瘤、抑菌、降血糖等多种生理作用的研究进展。并对今后的研究方向进行展望,以期为药用植物内生真菌多糖的开发利用提供参考。 相似文献
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纳米硒的制备与应用研究进展 总被引:1,自引:0,他引:1
硒是生物体必需的微量元素之一,具有重要的生理功能,而纳米硒具有毒性低、生物活性高等特征.综述了载体/模板法、溶胶法、固相法等纳米硒的制备与保护方法,并简要介绍了纳米硒在保健食品、医药以及饲料添加剂等领域中的应用. 相似文献
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Sandra Grska-Jakubowska Marzenna Klimaszewska Piotr Podsadni Beata Kaleta Radosaw Zagodon Sabina Grska Andrzej Gamian Tomasz Strczek Czesaw Kapusta Marcin Cielak Julia Ka
mierczak-Baraska Barbara Nawrot Jadwiga Turo 《International journal of molecular sciences》2021,22(23)
In continuation of our research on the influence of selenium incorporation on the biosynthesis, structure, and immunomodulatory and antioxidant activities of polysaccharides of fungal origin, we have isolated from a post-culture medium of Lentinula edodes a selenium (Se)-containing exopolysaccharide fraction composed mainly of a highly branched 1-6-α-mannoprotein of molecular weight 4.5 × 106 Da, with 15% protein component. The structure of this fraction resembled mannoproteins isolated from yeast and other mushroom cultures, but it was characterized by a significantly higher molecular weight. X-ray absorption fine structure spectral analysis in the near edge region (XANES) suggested that selenium in the Se-exopolysaccharide structure was present mainly at the IV oxidation state. The simulation analysis in the EXAFS region suggested the presence of two oxygen atoms in the region surrounding the selenium. On the grounds of our previous studies, we hypothesized that selenium-enriched exopolysaccharides would possess higher biological activity than the non-Se-enriched reference fraction. To perform structure–activity studies, we conducted the same tests of biological activity as for previously obtained mycelial Se-polyglucans. The Se-enriched exopolysaccharide fraction significantly enhanced cell viability when incubated with normal (human umbilical vein endothelial cells (HUVEC)) cells (but this effect was absent for malignant human cervical HeLa cells) and this fraction also protected the cells from oxidative stress conditions. The results of tests on the proliferation of human peripheral blood mononuclear cells suggested a selective immunosuppressive activity, like previously tested Se-polyglucans isolated from L. edodes mycelium. The Se-exopolysaccharide fraction, in concentrations of 10–100 µg/mL, inhibited human T lymphocyte proliferation induced by mitogens, without significant effects on B lymphocytes. As with previously obtained Se-polyglucans, in the currently tested Se-polymannans, the selenium content increased the biological activity. However, the activity of selenium exopolysaccharides in all tests was significantly lower than that of previously tested mycelial isolates, most likely due to a different mode of selenium binding and its higher degree of oxidation. 相似文献
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以自制的浒苔多糖为原料,在硝酸催化下与亚硒酸钠进行硒化反应,制备了浒苔硒多糖。通过单因素实验和正交实验确定最佳合成条件为:亚硒酸钠与浒苔多糖的质量比1.0∶1、反应时间8h、反应温度60℃、硝酸体积分数0.5%,此条件下合成的浒苔硒多糖的硒含量为512.3μg.g-1,其单糖组成为D-甘露糖∶L-鼠李糖∶D-半乳糖醛酸∶D-葡萄糖∶D-木糖=0.01∶0.80∶0.12∶0.65∶0.09(物质的量比)。光谱分析表明产品中含有亚硒酸酯基团。与浒苔多糖相比,浒苔硒多糖清除有机自由基DPPH的能力明显增强,在1.0~10.0mg.mL-1浓度范围内具有一定的还原能力,但清除羟自由基(.OH)的能力变化不大。 相似文献
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评述了腐植酸、微量元素锌和硒的生物学效应、生理功能和药用价值.提出合成腐植酸锌和硒络合物的研究构想、潜在意义和前景预测.并指出今后研究的课题。 相似文献
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Analyzing Xyloglucan Endotransglycosylases by Incorporating Synthetic Oligosaccharides into Plant Cell Walls
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Dr. Colin Ruprecht Pietro Dallabernardina Peter J. Smith Dr. Breeanna R. Urbanowicz Dr. Fabian Pfrengle 《Chembiochem : a European journal of chemical biology》2018,19(8):793-798
The plant cell wall is a cellular exoskeleton consisting predominantly of a complex polysaccharide network that defines the shape of cells. During growth, this network can be loosened through the action of xyloglucan endotransglycosylases (XETs), glycoside hydrolases that “cut and paste” xyloglucan polysaccharides through a transglycosylation process. We have analyzed cohorts of XETs in different plant species to evaluate the substrate specificities of xyloglucan acceptors by using a set of synthetic oligosaccharides obtained by automated glycan assembly. The ability of XETs to incorporate the oligosaccharides into polysaccharides printed as microarrays and into stem sections of Arabidopsis thaliana, beans, and peas was assessed. We found that single xylose substitutions are sufficient for transfer, and xylosylation of the terminal glucose residue is not required by XETs, independent of plant species. To obtain information on the potential xylosylation pattern of the natural acceptor of XETs, that is, the nonreducing end of xyloglucan, we further tested the activity of xyloglucan xylosyl transferase (XXT) 2 on the synthetic xyloglucan oligosaccharides. These data shed light on inconsistencies between previous studies towards determining the acceptor substrate specificities of XETs and have important implications for further understanding plant cell wall polysaccharide synthesis and remodeling. 相似文献