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1.
坛紫莱多糖的分离纯化和结构分析(Ⅱ)   总被引:2,自引:0,他引:2  
对广东产坛紫菜沸水提取多糖采用Sevag法脱蛋白,冻干后得粗多糖,得率为8%。在粗多糖溶中加入CTAB以沉淀除去酸性多糖PP1,超滤以纯化中性多糖PP2,PP2经DEAE-纤维素、葡聚糖凝胶G200进一步纯化。经纸层析、凝胶过滤及紫外光谱分析鉴定为纯品。通过红外光谱、气相色谱对PP2进行组成分析,再用化学方法测定其总糖,3,6-内醚-L-半乳糖及硫酸基的含量,分别为86.33%、5.425%和12.2%。最后通过高碘酸氧化,Smith降解等方法测定PP2的化学结构,结果表明,PP2由半乳糖、3,6-内醚-L-半乳糖、甘露糖、葡萄糖、木糖和阿拉伯糖组成,具有α,β型糖苷键,连接方式有(1→3)、(1→4)、(1→2)3种。PP1分子量通过凝胶过滤法初步测得为16.2万左右。  相似文献   

2.
莪术多糖的分离纯化   总被引:2,自引:0,他引:2  
研究莪术多糖分离纯化的最佳条件,优化莪术多糖的提取纯化工艺,为进一步探讨莪术多糖的生物活性奠定基础.莪术经热水提取,酒精沉淀,脱色,脱蛋白得粗多糖.粗多糖用50%、75%乙醇分级沉淀得2个级分CZ1、CZ2,进行DEAE-纤维素柱层析.调节DEAE-纤维素的pH值,比较洗脱曲线的不同.CZ1经DEAE-纤维素柱层析得到1个组分,CZ2在酸性、中性条件下层析得2个组分,在碱性条件下得1个组分,随pH升高,回收率降低,纯度增高.各纯化得到的多糖组分经纸层析、琼脂糖凝胶电泳鉴定为单一成分.实验证明,pH是影响层析的一个重要因素,因此莪术多糖的最佳纯化pH值为7.0.  相似文献   

3.
坛紫菜多糖的分离纯化和结构分析(Ⅱ)   总被引:1,自引:0,他引:1  
对广东产坛紫菜沸水提取多糖采用Sevag法脱蛋白 ,冻干后得粗多糖 ,得率为 8%.在粗多糖溶液中加入CTAB以沉淀除去酸性多糖PP1,超滤以纯化中性多糖PP2 ,PP2经DEAE 纤维素、葡聚糖凝胶G2 0 0进一步纯化 .经纸层析、凝胶过滤及紫外光谱分析鉴定为纯品 .通过红外光谱、气相色谱对PP2进行组成分析 ,再用化学方法测定其总糖 ,3,6 内醚 L 半乳糖及硫酸基的含量 ,分别为 86 .33%、5.4 2 5%和 12 .2 %.最后通过高碘酸氧化 ,Smith降解等方法测定PP2的化学结构 ,结果表明 ,PP2由半乳糖、3,6 内醚 L 半乳糖、甘露糖、葡萄糖、木糖和阿拉伯糖组成 ,具有α ,β型糖苷键 ,连接方式有 (1→ 3)、(1→ 4 )、(1→ 2 ) 3种 .PP1分子量通过凝胶过滤法初步测得为 16 .2万左右 .  相似文献   

4.
以蛹虫草菌丝体粗多糖为材料进行分离纯化及性质的研究.提取液浓缩用3倍体积乙醇沉淀,等电点Sevag法除蛋白,10%H2O2脱色,得到的粗多糖经DEAE-DE52纤维素柱层析,用0~0.2mol/L的NaCl洗脱,可以得到未完全分离的多糖.将此多糖经Sephadex-G200柱层析,用蒸馏水洗脱.将多糖用Sepharose CL-6B柱层析进行纯度鉴定,经验证是单一多糖.对多糖进行纸层析,证明组分是D-葡萄糖和D-半乳糖.用高效液相色谱法测定多糖分子质量为3.76×104ku.以昆明种小鼠对多糖进行生物活性研究,多糖对小鼠S180肉瘤抑制率达到71.92%.  相似文献   

5.
蕨麻水溶性多糖的提取及其单糖组分的分析   总被引:3,自引:0,他引:3  
本文采用热水提取、乙醇沉淀、a-淀粉酶法脱淀粉、链酶蛋白酶和Sevag法联合除蛋白,得到蕨麻多糖.对提取的蕨麻多糖进行了总糖含量及糖醛酸含量的测定.粗多糖(P1)总糖含量为41.8%,糖醛酸含量为11.1%.脱淀粉脱蛋白多糖(P2)总糖含量为39.4%,糖醛酸含量为35.9%.经纸层析和高效液相色谱分析,表明该多糖主要由阿拉伯糖、鼠李糖、葡萄糖、半乳糖、半乳糖醛酸组成,说明蕨麻多糖为酸性杂多糖.  相似文献   

6.
灰树花子实体多糖和菌丝体多糖的比较分析   总被引:8,自引:0,他引:8  
从灰树花 (Grifolafrondosa)子实体和菌丝体中提取分离得到子实体多糖F -D和菌丝体多糖M -D ,得率分别是 0 .5 9%、0 .31% ;F -D的糖、蛋白质含量为 6 4 .8%、15 .6 % ,M -D糖、蛋白质含量是 6 5 .9%、7.37% ;气相色谱分析单糖组成 ,F -D由岩藻糖、阿拉伯糖、木糖、甘露糖、半乳糖、葡萄糖组成 ,各单糖的摩尔比为 0 .9:0 .5 :1.3:5 .0 :2 .9:10 0 .0 ;M -D由鼠李糖、岩藻糖、阿拉伯糖、木糖、甘露糖、半乳糖、葡萄糖组成 ,各单糖的摩尔比为 5 .9:8.5 :3.2 :2 3.2 :6 .5 :11.7:10 0 .0 ;红外光谱图显示F -D和M -D约在 890cm- 1处有吸收 ,1H -NMR谱显示两者在 5mg/L以上均无吸收 ,13C -NMR谱显示两者在 10 5× 10 - 6 、86× 10 - 6 、和 71× 10 - 6 处均有吸收 ,提示F -D和M -D多糖中均存在 β(1→ 3)和 (1→ 6 )糖苷键。  相似文献   

7.
对条斑紫菜蛋白酶解获得的血管紧张素转换酶抑制肽(ACEI)进行纯化和结构鉴定,并研究了条斑紫菜ACEI肽体外贮存稳定性和对原发性高血压大鼠的降血压作用.结果表明:通过2步反相高效液相制备色谱纯化得到2种单一组分ACEI肽,经液质联用质谱分析肽序列分别为Cys-Ser-Asn-Arg和Pro-Cys-His-Trp,二者对血管紧张素转换酶半数抑制浓度分别为24.71和5.38 μmol·L-1;条斑紫菜ACEI肽不耐高温,在中性或酸性条件下较稳定;用分子质量小于3 ku条斑紫菜ACEI肽组分对原发性高血压大鼠灌胃后有显著降血压效果,且降血压幅度随灌胃剂量增大而提高.  相似文献   

8.
文章采用醇沉分级法来获取和纯化枳椇多糖,并研究各组分的理化性质及免疫调节活性。从枳椇肉质果柄中提取粗多糖,用蒸馏水洗脱过DEAE纤维素柱后进行分级醇沉,获得了醇沉组分HDP1-1、HDP1-2和HDP1-3,研究了其化学成分、单糖组成、分子量分布、红外吸收特征峰及其对巨噬细胞的免疫调节活性。结果表明,总糖质量分数分别为(97.26±0.17)%、(92.90±1.02)%和(95.48±2.45)%;HDP1-1是分子量为2 187kDa的均一性多糖,由半乳糖组成;HDP1-2和HDP1-3主要由葡萄糖、鼠李糖和半乳糖组成,其中HDP1-3还含有少量木糖;红外光谱分析表明各醇沉组分均具有多糖的特征吸收峰。免疫调节活性实验表明,HDP1-3在巨噬细胞增殖、NO产量和中性红吞噬实验中,比其他2个组分对巨噬细胞的刺激作用更强。  相似文献   

9.
牛舌菌(Fistulinahepatica)子实体经热水抽提,乙醇沉淀,蛋白酶法和Sevag法去蛋白后得粗多糖FHP.FHP经DEAE-纤维素和SephadexG-200柱进一步纯化得到牛舌菌多糖纯品FHP-2P.经测定该多糖为均一组分,相对分子质量为7.6×104.红外扫描呈现出典型的多糖吸收峰,并含有β-型糖苷连接键;紫外扫描无核酸和蛋白质的特征吸收峰.纸层析和气相色谱分析结果表明FHP-2P的单糖组成为D-葡萄糖、D-甘露糖、D-半乳糖和D-木糖,其摩尔比为13.9∶2.85∶3.25∶0.48.  相似文献   

10.
白沙蒿籽多糖的分离纯化及结构研究   总被引:1,自引:0,他引:1  
以白沙蒿籽为原料,经水提醇沉,酶法和Seveg法脱蛋白,乙醇分级沉淀,得到两种酸性多糖ASP1和ASP2.将ASP1和ASP2分别完全酸水解、高碘酸氧化、Smith降解后经高效液相色谱分析表明ASP1主要成分是木糖,含有少量葡萄糖和阿拉伯糖,数均分子量2.84×105,ASP2由葡萄糖、半乳糖、阿拉伯糖和甘露糖组成,摩尔比为2.1:1.3:1.0:1.4,数均分子量3.50×104,ASP1中糖苷键以1→3连接为主,ASP2中糖苷键以1→4连接为主,红外光谱及核磁共振光谱表明ASP1,ASP2中均含有糖醛酸为酸性多糖,且均含有α和β两种构型.  相似文献   

11.
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   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
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   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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