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1.
鸡腿菇子实体多糖分离纯化和光谱分析   总被引:1,自引:0,他引:1  
从鸡腿菇子实体中提取纯化多糖,鉴定其纯度并测定其结构.利用水浴浸提、乙醇沉淀多糖、TCA法去除蛋白质等工艺提取粗多糖;将得到的粗多糖通过DEAE-52柱层析和Sephadex G-200柱层析进行分离纯化,收集得到4个糖组分Ccp-Ⅰ-A、Ccp-Ⅰ-B、Ccp-Ⅱ-C和Ccp-Ⅱ-D;采用紫外分光光度计、红外光谱仪对多糖结构进行初步的光谱分析.  相似文献   

2.
北极海参多糖的分离纯化及抗肿瘤活性研究   总被引:1,自引:0,他引:1  
采用人肺癌细胞A549、人胃癌细胞SGC-7901、人乳腺癌细胞MCF-7及人胰腺癌细胞PANC-1共4种癌细胞株,通过MTT法研究北极海参多糖组分的体外抗肿瘤活性;利用胃蛋白酶、胰蛋白酶连续水解制备海参粗多糖,用sephadex G-50及DEAE-52分离纯化,得到Ⅱ-ⅠC、Ⅱ-ⅠD和Ⅱ-ⅠE 3种精制多糖;对3种精制多糖的组成及性质进行分析。结果表明:3种精制多糖对4种肿瘤细胞的抑制作用明显强于粗多糖,且与多糖质量浓度正相关;3种精制多糖对MCF-7的抑制作用最强,对A549的抑制作用相对较弱;实验浓度(0.02、0.04、0.06、0.08、0.10 mg/m L)下,Ⅱ-ⅠD和Ⅱ-ⅠE对A549的抑制作用显著强于Ⅱ-ⅠC;Ⅱ-ⅠD对MCF-7、SGC及PANC-1的抑制作用强于Ⅱ-ⅠE和Ⅱ-ⅠC;3种精制多糖的质量分数均大于93%,为不含肽链及核酸的β-吡喃构型,硫酸根的质量分数为31.52%~32.67%。单糖组成分析显示,3种多糖均属于海参硫酸软骨素。  相似文献   

3.
采用水体醇沉法得香菇多糖粗品,再通过分级醇沉及Sephadex G-200葡聚糖凝胶进一步分离纯化得到香菇多糖;用硫酸苯酚法测定香菇多糖含量,采用分子排阻色谱法测定香菇多糖分子量,用糖腈乙酸酯柱前衍生化-气相色谱法测定单糖组成,红外光谱(IR)测定多糖结构,结果显示:香菇多糖初次提取纯化的两个组分由β糖苷键岩藻聚糖构成,相对分子量分别为9.5×104和1.7×104.二次提取纯化多糖组分1由岩藻糖、阿拉伯糖、木糖、甘露糖、葡萄糖、半乳糖组成(3.6∶1.3∶1.2∶9.2∶63.3∶21.4),相对分子量4.2×104,以α糖苷键链接;组分2由岩藻糖、阿拉伯糖、木糖、甘露糖、葡萄糖、半乳糖组成(10.7∶1.5∶0.6∶14.2∶25.4∶47.5),相对分子量1.5×104,以β糖苷键链接.香菇多糖结构复杂,其化学结构与生物活性密切相关,通过对香菇多糖的分离纯化和结构表征,可为获取高活性多糖、提升多糖在食品和药品中的应用价值提供科学依据.  相似文献   

4.
野西瓜正丁醇提取物中化学成分研究   总被引:1,自引:1,他引:0  
对野西瓜Capparis spinosa L.中正丁醇提取物化学成分进行研究,为进一步探索野西瓜活性成分的分离提取方法及其充分开发利用提供科学依据.渗漉法阳离子交换树脂、索式提取法和硅胶柱色谱对野西瓜果实进行初步分离提取,结合反复硅胶柱色谱、Sephadex LH - 20和重结晶技术对正丁醇部位的浸膏进行分离纯化,并...  相似文献   

5.
目的:找到一种操作简单、结果准确的香菇多糖提取及分子量测定的方法。方法:用水煮醇沉法提取香菇多糖,用蒽酮-硫酸法在621nm波长下,测定吸光度值计算糖含量,通过Sephadex-LH20柱,分离得到分子量范围不同的三段组分,GPC测定分子量范围。结果:蒽酮-硫酸法测定得到香菇多糖的糖含量为52.3%,经GPC测定三段组分分子量范围分别为27w、1w、300D。结论:结果表明,水煮醇沉法提取香菇多糖操作简单,柱分离纯化后,GPC测定分子量结果准确。  相似文献   

6.
目的:找到一种操作简单、结果准确的香菇多糖提取及分子量测定的方法。方法:用水煮醇沉法提取香菇多糖,用蒽酮-硫酸法在621nm波长下,测定吸光度值计算糖含量,通过Sephadex-LH20柱,分离得到分子量范围不同的三段组分,GPC测定分子量范围。结果:蒽酮-硫酸法测定得到香菇多糖的糖含量为52.3%,经GPC测定三段组分分子量范围分别为27w、1w、300D。结论:结果表明,水煮醇沉法提取香菇多糖操作简单,柱分离纯化后,GPC测定分子量结果准确。  相似文献   

7.
目的:研究菊芋多糖的降血糖及抗病毒作用,开发菊芋的药用价值.方法:水提醇沉法提取多糖、Sevag法纯化,以苯酚-硫酸法对菊芋多糖的纯度进行测定;采用四氧嘧啶高糖小鼠造模法造模,以不同剂量给药,测定小鼠的血糖值,观察其活动状况和体质量变化;将纯化后的菊芋多糖进行体外抗病毒实验,通过显微镜观察细胞病变效应(CPE),噻唑蓝(MTT)法染色,酶标仪测定吸光度值,计算治疗指数(TI).结果:经纯化后的菊芋多糖纯度为71.54%,提取率为68.99%,多糖含量较高;经降血糖实验发现,菊芋多糖有良好的降血糖作用;在细胞水平下,通过抗病毒实验得,菊芋多糖对HSV-1、RSV、EV-71病毒均有一定程度的抑制效果,其TI为分别为9.849、51.191、13.826.结论:菊芋多糖具有降血糖和抗病毒的作用,药物安全性好,有较高的开发价值.  相似文献   

8.
通过多糖提取分离技术对羊肚菌子实体中的多糖进行分离纯化.利用水提醇沉法对其进行分离,利用离子交换柱和凝胶柱层析,高效凝胶渗透柱色谱对其进行分离纯化.得到3个多糖化合物,分别为:MEWP-H_2O-Ⅱa、MEWP-H_2O-Ⅱb及MEWP-H_2O-Ⅱc.  相似文献   

9.
野生榛蘑多糖采用水提法得到多糖粗品,经Sevage法除蛋白,H2O2法脱色素和透析法去除小分子后,采用DEAE-纤维素柱层析纯化,分离得三种多糖成分Ⅰ,Ⅱ和Ⅲ.纯化得的榛蘑多糖经葡聚糖凝胶层析法测得相对分子量分别为132429,93917,74687 Da.  相似文献   

10.
春砂仁多糖的提取及组分分析   总被引:3,自引:0,他引:3  
报道春砂仁多糖的分离纯化及结构分析的研究.以凝胶过滤色谱法测定春砂仁多糖的数量及分子量,结果显示:春砂仁主要含两种多糖,其数均分子量分别为56 421及1 743;多糖经酸解成为单糖并衍生为乙酰化的糖肟,对照标样采用气相色谱法测定其单糖组分为阿拉伯糖、甘露糖、葡萄糖及半乳糖,4种单糖含量的相对比例:1.00∶0.68∶0.97∶0.86.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

14.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

15.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

16.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

17.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

18.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
The non-orthogonal localized molecular orbital(NOLMO)is the most localized representation of electronic degrees of freedom.As such,NOLMOs are thus potentially the most efficient for linear scaling calculations of electronic structures for large systems.However,direct ab initio calculations with NOLMO have not been fully implemented and widely used,partly because of the slow convergence issue in the optimization of NOLMO.We devel-  相似文献   

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