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1.
羊肚菌(Morchella spp.)是一种珍稀食药用真菌,从羊肚菌中提取的多糖在抗癌、抗氧化、降血糖、降血脂及免疫调节等方面具有良好的生物活性,在食品、药品和保健品开发方面具有广阔的应用前景。羊肚菌多糖的有效提取是对其进行结构解析和生物活性研究的基础,不同的提取方式对羊肚菌多糖的结构和生物活性具有一定影响。羊肚菌多糖的结构特性如分子量、单糖组成、一级结构等,对其生物活性具有很大影响,因此研究羊肚菌多糖的结构对揭示其生物活性及作用机制具有重要意义。针对羊肚菌多糖进行综述,总结羊肚菌多糖提取分离、结构解析及生物活性的研究进展,分析羊肚菌多糖生物活性的作用机制,并对今后研究方向提出展望,以期为羊肚菌多糖的研究与开发提供理论基础。  相似文献   

2.
[目的]探究从羊肚菌发酵液中提取胞外多糖的最佳工艺。[方法]实验原料为羊肚菌发酵液,采用单因素实验的方法探究在不同醇沉浓度、醇沉温度、醇沉时间、醇沉p H的条件下,运用正交实验分析从羊肚菌发酵液中提取多糖的最佳工艺条件;根据实验结果,提取7 d中羊肚菌胞外多糖,分别绘制多糖变化曲线和菌丝体生物量曲线。[结果]通过对羊肚菌胞外多糖提取的研究得到最佳工艺条件为:醇沉浓度95%,醇沉温度-25℃,醇沉时间24 h,醇沉p H 7。[结论]利用优化后的实验条件得出,羊肚菌胞外多糖含量最高为0. 874 g/L,在一定程度上为羊肚菌胞外多糖的研究提供了依据,具有十分重要的意义。  相似文献   

3.
通过液体深层发酵获得羊肚菌菌丝体和发酵液为羊肚菌的开发利用提供了新的途径,本文以胞内多糖和胞外多糖为综合指标,对羊肚菌的最佳培养基组成进行了优化,并对羊肚菌发酵液的成分进行了分析。  相似文献   

4.
为了探讨碱法提取羊肚菌多糖的工艺条件并测定其抗氧化活性,该研究以四川北川羊肚菌为原料,采用碱法提取羊肚菌多糖,利用苯酚-硫酸法对羊肚菌多糖得率进行测定,并通过单因素探讨提取温度(70、80、90、100℃)、提取时间(2、4、6、8 h)、碱液浓度(0.4、0.6、0.8、1.0 mol·L~(-1))、料液比(1∶15、1∶20、1∶25、1∶30 g·mL~(-1))对羊肚菌多糖得率的影响,同时采用正交试验优化提取工艺,对其抗氧化活性进行测定。结果表明:在提取温度90℃、提取时间5 h、碱液浓度0.7 mol·L~(-1)、料液比1∶20(g·mL~(-1))条件下得到的羊肚菌多糖得率为5.39%。羊肚菌多糖具有较强的清除DPPH自由基、羟自由基、超氧阴离子的能力和较好的还原能力,其IC50分别为0.468、0.208、0.022、0.014 mg·mL~(-1),抗氧化能力依次为还原能力超氧阴离子清除能力羟自由基清除能力DPPH自由基清除能力。优化后的羊肚菌多糖提取工艺合理、可行,且羊肚菌多糖具有较强的抗氧化活性。  相似文献   

5.
马利  李霞  张松 《菌物学报》2014,33(2):385-393
不同浓度尖顶羊肚菌胞外多糖提取物作用人皮肤成纤维细胞(human skin fibroblasts,HSF),检测对HSF细胞形态、细胞增殖、衰老相关β‐半乳糖苷酶活性、羟脯氨酸含量的影响,探究尖顶羊肚菌胞外多糖提取物对HSF增殖和衰老的影响。结果显示,125μg/mL尖顶羊肚菌胞外多糖提取物使HSF细胞活力增加了25.2%,羟脯氨酸含量增加了12.1%,β‐半乳糖苷酶活性降低了48.1%。说明适宜浓度尖顶羊肚菌胞外多糖提取物具有促进HSF细胞增殖、胶原蛋白合成,延缓细胞衰老的作用。  相似文献   

6.
分离纯化人工栽培的六妹羊肚菌子实体多糖,对其结构和抗氧化活性进行研究。采用水提醇沉法提取六妹羊肚菌子实体多糖(MSP),采用DE-52纤维素柱和Sephadex G-100进行多糖的分离纯化,借助HPGPC和HPLC测定多糖分子量及单糖组成。通过DPPH自由基、羟自由基和超氧阴离子自由基的清除作用,评估其体外抗氧化活性。构建H_2O_2介导的氧化压力损伤的PC12细胞模型,评估其基于抗氧化的神经保护作用。结果显示,六妹羊肚菌水溶性多糖平均分子量为287 588 Da,单糖组成为甘露糖,葡萄糖和半乳糖,占比约为9∶1∶6。六妹羊肚菌多糖具有优良的自由基清除活性,同时,能够通过重塑SOD、CAT、GSH-Px等抗氧化酶系活性,缓解H_2O_2诱发的氧化压力的细胞损伤,抑制PC12细胞凋亡。涉及通路为Bax/Bcl及Caspase。六妹羊肚菌水溶性多糖具有优良的抗氧化活性,表现出一定的神经保护作用。  相似文献   

7.
为提高羊肚菌多糖体外降血糖能力,本试验在筛选羊肚菌多糖改性方法的基础上,以α-淀粉酶抑制率为参数,运用单因素试验结合响应面分析法建立了羊肚菌多糖改性产物对α-淀粉酶抑制率的多元二次回归方程模型,优化了羊肚菌多糖过氧化氢氧化降解工艺条件。试验表明料液比为1∶8.55、pH为7.09、温度为47.8℃、时间为3.02 h的条件下的改性效果最好,在该条件下重复测定三次所得羊肚菌多糖过氧化氢氧化改性产物的α-淀粉酶抑制率为16.30%±1.22%,与模型预测结果的相对误差为0.11%,是改性前的17.16倍。同时,蔗糖酶抑制率为78.13%±5.09%,麦芽糖酶抑制率为16.48%±3.27%,α-葡萄糖苷酶抑制率为21.40%±3.81%,分别比改性前提高了1.07倍、1.64倍、1.22倍。与常用的降糖药阿卡波糖相比,羊肚菌多糖改性产物的α-淀粉酶抑制率、麦芽糖酶抑制率、α-葡萄糖苷酶抑制率分别提高了1.44、1.63和1.88倍,蔗糖酶抑制率与阿卡波糖差异不显著(P0.05)。羊肚菌多糖经过氧化氢氧化改性的产物呈现明显的多糖红外吸收特征,对糖苷酶抑制效果显著提升,提高了其体外降血糖能力。  相似文献   

8.
对羊肚菌多糖的结构和免疫调节活性进行初步探究,采用热水浸提法提取羊肚菌粗多糖,DEAE纤维素柱层析法对粗多糖进行分离纯化,CCK-8法检测羊肚菌多糖免疫调节能力。结果显示:分离纯化后的羊肚菌多糖(ME-X)重均分子量为1. 635×10~4。ME-X能显著提高免疫细胞增殖能力,当其质量浓度为10μg/mL时,淋巴细胞T、B的增殖效果最佳,增殖率分别达到31. 18%、63. 02%;质量浓度为20μg/mL时,巨噬细胞增殖效果最好,增殖率高达63. 12%,同时该浓度值的ME-X刺激巨噬细胞吞噬中性红能力也最强,吞噬率为22. 49%。ME-X的活性探究实验表明,ME-X能有效促进免疫细胞增殖,同时能显著促进巨噬细胞的吞噬作用。  相似文献   

9.
王珍珍  官月  刘洋  刘淑艳 《菌物学报》2019,38(9):1548-1558
六妹羊肚菌Morchella sextelata是一种珍贵的食药用真菌,具有重要的经济价值。本研究在单因素试验基础上,采用响应面分析法优化其多糖提取工艺,利用Sevage法及透析法对粗多糖进行初步纯化,获得六妹羊肚菌多糖(Morchella sextelata polysaccharide,MSP)组分。采用凝胶色谱-示差-多角度激光光散射(gel permeation chromatography- refractive index-multi angle laser light scattering,GPC-RI-MALLS)、高效阴离子交换色谱(high performance anion exchange chromatography,HPAEC)、傅里叶变换红外光谱仪(fourier transform infrared spectrometer,FTIR)和气相色谱质谱联用仪(gas chromatography-mass spectrometry,GC-MS)等对其进行结构分析,并检测了该多糖清除自由基活性的能力。结果表明,六妹羊肚菌多糖最优提取工艺为:提取温度89.94℃、液料比31.07mL/g、提取时间162.86min。在此工艺条件下,提取率为23.98%。该多糖主要由分子量为4.655×10 6Da和6.571×10 4Da的两个组分组成,其单糖组成为葡萄糖、甘露糖、半乳糖,摩尔百分比分别为71.60%、23.70%和4.70%。该多糖的糖苷键主要有T-Glc、1,2-Man、1,4-Glc、1,6-Man、1,3,4-Man、1,4,6-Gal。此外,该多糖具有较强的清除2,2‐联氮基双‐3‐乙基苯并噻唑啉‐6‐磺酸[2,2‐azino bis (3‐ethylbenzothiazoline‐6‐sulfonic acid),ABTS]、1,1‐二苯基‐2‐苦基肼(1,1‐diphenyl‐2‐picrylhydrazyl,DPPH)和羟自由基活性的能力。本研究结果为六妹羊肚菌多糖功能食品的开发和利用提供研究基础。  相似文献   

10.
基于遗传算法的羊肚菌液体发酵动力学模型的建立   总被引:1,自引:1,他引:0  
发酵动力学研究是实现发酵过程最优化控制及发酵过程放大的前提条件。本研究对羊肚菌液体深层发酵动力学进行了研究, 在Matlab软件平台上, 应用遗传算法对比了真菌生长较常用的Monod与Logistic方程在描述羊肚菌生长动力学时的优劣, 并对羊肚菌的生长、胞外多糖产生和基质消耗模型进行了参数估计。结果表明, Logistic方程与试验数据拟和情况更好, 并给出了羊肚菌液体深层发酵的动力学模型具体形式, 经验证, 模型的平均误差为5.8%。利用遗传算法选择羊肚菌动力学模型, 并进行参数估计与其他方法相比具有快速、搜索面广、接近全局最优解的特点, 在处理分批发酵动力学问题上具有不可比拟的优势, 发酵动力学模型的建立为发酵过程优化及放大奠定了基础。  相似文献   

11.
The structures of the capsular polysaccharides (S-15B and S-15C) from Streptococcus pneumoniae types 15B and 15C have been investigated by using n.m.r. spectroscopy, methylation analysis, and various specific degradations. It is concluded that the polysaccharides are composed of pentasaccharide repeating-units having the following structure: (Formula: see text). In this structure, R is H (80%) or CH2CH2N+Me3 (20%). S-15B further contains O-acetyl groups, approximately 0.7 per repeating unit, which have not been located. The capsular polysaccharides S-15F and S-15A, which have been studied previously, are also composed of pentasaccharide repeating-units, containing the same sequence of sugars, but in a linear arrangement.  相似文献   

12.
Six polysaccharides were extracted sequentially from the fresh sclerotium of Poria cocos cultivated in China using 0.9% NaCl (PCS1), hot water (PCS2), 0.5M NaOH (PCS3-I and PCS3-II), and 88% formic acid (PCS4-I and PCS4-II). Their chemical and physical characteristics were determined using infrared spectroscopy (IR), gas chromatography (GC), GC-MS methylation analysis, 13C NMR spectroscopy, elementary analysis (EA), protein analysis, size exclusion chromatography combined with laser light scattering (SEC-LLS), light scattering (LS), and viscometry. The results indicated that the polysaccharides PCS1, PCS2, and PCS3-I were heteropolysaccharides containing D-glucose, D-galactose, D-mannose, D-fucose, and D-xylose; the predominant monosaccharide was D-glucose except for PCS1 where it was D-galactose. PCS3-II, the main component of the sclerotium of P. cocos, was a linear (1-->3)-beta-D-glucan of high purity. PCS4-I consisted of (1-->3)-beta-D-glucan with some beta-(1-->6) linked branches. PCS4-II was mainly composed of (1-->3)-beta-D-glucan containing some glucose branches. The M(w) values of the six polysaccharides PCS1, PCS2, PCS3-I, PCS4-I in 0.2M NaCl aqueous solution, PCS3-II, and PCS4-II in dimethyl sulfoxide (Me(2)SO) were determined to be 11.6 x 10(4), 20.8 x 10(4), 17.1 x 10(4), 9.1 x 10(4), 12.3 x 10(4), and 21.1 x 10(4), respectively. The six polysaccharides in aqueous solution or Me(2)SO exist as flexible chains.  相似文献   

13.
The O-antigen polysaccharides of Klebsiella serotype O5 and Escherichia coli serotype O8 are serologically very similar or identical. The structures of these two polysaccharides have now been re-investigated. N.m.r. spectroscopy, chromium trioxide oxidation, hydrolysis with a specific phage enzyme, and f.a.b. mass spectrometry were the principal methods used. It is concluded that the O-antigen has the following structure, in which D-Man3Me is 3-O-methyl-D-mannose and n is approximately 10. (Formula: see text) Biosynthetic studies indicate that these antigens are synthesised by addition of D-mannopyranosyl groups to the "non-reducing" end of the mannan chain, and it seems possible that addition of a 3-O-methyl-D-mannopyranosyl group involves termination.  相似文献   

14.
The 4,6-O-(1-methoxycarbonylethylidene), -(hydroxyisopropylidene), and -(methoxyisopropylidene) acetals of methyl 2,3-di-O-methyl-alpha-D-glucopyranoside were subjected to reductive cleavage in the presence of triethylsilane and trimethylsilyl methanesulfonate-boron trifluoride etherate (Me3SiOMs-BF3.Et2O), BF3.Et2O, or trimethylsilyl trifluoromethanesulfonate (Me3SiOSO2CF3) and the mole fractions of products were determined as a function of reaction time. The 4,6-(1-methoxycarbonylethylidene) acetal was quite stable to reductive-cleavage conditions but isomerization of the initial R,S mixture of diastereomers to the more-stable S diastereoisomer was noted. In addition, a slow, regiospecific, reductive ring-opening of the acetal was observed to give 6-O-[1-(methoxycarbonyl)ethyl] derivatives. The 4,6-(hydroxyisopropylidene) acetal was very unstable under reductive-cleavage conditions. Both Me3SiOMs-BF3.Et2O and Me3SiOSO2CF3 catalyzed complete removal of the group, via the intermediate 6-[1-(hydroxymethyl)ethyl] ether, but BF3.Et2O gave a mixture of products. The 4,6-(methoxyisopropylidene) acetal was also very labile under reductive-cleavage conditions; Me3SiOMs-BF3.Et2O catalyzed complete removal of the acetal, via the intermediate 6-[1-(methoxymethyl)ethyl]ether, but the intermediate ether was quite stable in the presence of either BF3.Et2O or Me3SiOSO2CF3. It is concluded from these studies that polysaccharides bearing 4,6-O-(1-carboxyethylidene) substituents can be analyzed directly by sequential permethylation and reductive cleavage. It is proposed that the identity of the substituted monomer and the positions of substitution of the acetal can be determined by sequential permethylation, ester reduction, and reductive cleavage.  相似文献   

15.
Starch, amylopectin, inulin, pullulan and methyl α- -glucopyranoside (Me α-Glcp) were oxidised by 4-acetamido-2,2,6,6-tetramethylpiperidine-1-oxyl (4-AcNH-TEMPO) as the mediator and peracetic acid or monoperoxysulfate (Oxone®) as the regenerating oxidant. The conversion of primary alcohol groups to the corresponding carboxyl groups proceeded with high yield and selectivity, provided that sodium bromide was added as co-catalyst.The mass molecular distributions of the oxidised polysaccharides indicated that no major depolymerisation occurred during oxidation. Oxone appeared to be the most efficient oxidant as the reaction rate was 25 times higher than that of peracetic acid in the oxidation of Me α-Glcp. On the other hand, oxone produces a larger amount of waste as by-product than peracetic acid.  相似文献   

16.
A mixture of two structurally distinct neutral O-polysaccharides was obtained by mild acid degradation of the lipopolysaccharide isolated by the phenol/water extraction from the asymbiotic diazotrophic rhizobacterium Azospirillum brasilense S17. The following structures of the O-polysaccharides were established by composition and methylation analyses, Smith degradation, and 1H and 13C NMR spectroscopy, including a 2D NOESY experiment: [Formula: see text] where L-Rha2Me stands for 2-O-methyl-L-rhamnose and SHb for the (S)-3-hydroxybutanoyl group. The occurrence of two distinct polysaccharides is reported for the first time in Azospirillum spp.  相似文献   

17.
研究发现,多糖的生物活性不仅与其一级结构(如分支度、单糖组成及糖苷键连接方式等)有关,而且与其空间结构也密不可分。 因此,对多糖高级结构的研究将有助于阐释其构效关系,为寻找具有生物活性的多糖和开发多糖药物提供理论依据。传统的多糖结构分 析方法具有一定的局限性,已不能满足多糖研究的需求,而现代物理技术的发展则为多糖高级结构解析提供了新的手段。综述近年来多 糖高级结构解析方法的研究进展。  相似文献   

18.
Hydrodynamic properties of connective-tissue polysaccharides.   总被引:2,自引:0,他引:2       下载免费PDF全文
The major hydrodynamic properties of the connective-tissue polysaccharides are those that describe polysaccharide-water interaction as embodied in their osmotic-pressure and hydraulic-conductivity properties. This study shows that, for polysaccharides such as chondroitin sulphate, hyaluronate and the heparin-like polysaccharides, their hydrodynamic properties depend primarily on the presence of the uronic residue and the nature of the glycosidic linkage. Other parameters such as the degree of N-acetylation and sulphation were found not to influence these properties to any great extent. These studies particularly delineate structural-functional aspects of the connective-tissue polysaccharides in terms of their primary structure.  相似文献   

19.
Here, we show the binding results of a leguminosae lectin, winged bean basic agglutinin (WBA I) to N-trifluoroacetylgalactosamine (NTFAGalN), methyl-α-N-trifluoroacetylgalactosamine (MeαNTFAGalN) and methyl-β-tifluoroacetylgalactosamine (MeβNTFAGalN) using 19?F NMR spectroscopy. No chemical shift difference between the free and bound states for NTFAGalN and MeβNTFAGalN, and 0.01-ppm chemical shift change for MeαNTFAGalN, demonstrate that the MeαNTFAGalN has a sufficiently long residence time on the protein binding site as compared to MeβNTFAGalN and the free anomers of NTFAGalN. The sugar anomers were found in slow exchange with the binding site of agglutinin. Consequently, we obtained their binding parameters to the protein using line shape analyses. Aforementioned analyses of the activation parameters for the interactions of these saccharides indicate that the binding of α and β anomers of NTFAGalN and MeαNTFAGalN is controlled enthalpically, while that of MeβNTFAGalN is controlled entropically. This asserts the sterically constrained nature of the interaction of the MeβNTFAGalN with WBA I. These studies thus highlight a significant role of the conformation of the monosaccharide ligands for their recognition by WBA I.  相似文献   

20.
抗补体活性多糖   总被引:2,自引:0,他引:2  
补体系统在宿主免疫中具有重要的作用。近年来,由某些中药中纯化的多糖具有明显的抗补体作用。这些多糖大多数含有阿拉伯糖、半乳糖和半乳糖醛酸,分子量范围6.000到500.000。它们的结构很复杂,多为具聚鼠李半乳糖醛酸结构中心的酸性杂多糖和果胶类多糖。这些多糖的抗补体活性可能和整个大分子的结构有关。一旦发生降解活性就大为下降甚至消失。它们都可以经典的方式激活补体系统。大部分也可以改变的方式激活补体系统。  相似文献   

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