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1.
采用硅胶柱层析、薄层层析、Sephadex LH-20柱层析从红树内生真菌BYY-1的次级代谢产物中分离到化合物B1.通过乙酰化、NMR、HR ESI-Q-TOF MS等技术鉴定了化合物B1的结构,确定其为首次从红树内生真菌中分离到的化合物.运用MTT法和流式细胞术研究了化合物B1的抗肿瘤活性,结果表明,化合物B1可显...  相似文献   

2.
在寻找神农架植物内生真菌活性次级代谢产物的过程中,从七叶一枝花叶片内生真菌Penicillium sp.(NO.64)的马铃薯葡萄糖液体培养(PDB)中分离得到三个生物碱类化合物.通过NMR,MS等波谱学方法鉴定为嘧菌酯(azoxystrobin)1和2及一个线性二肽类衍生物3,3个化合物均为第一次从自然界中分离得到,同时也是第一次从植物内生真菌中获得.  相似文献   

3.
对南海红树林内生真菌Aspergillus sp.9H的次级代谢产物进行研究。利用土豆培养基对菌种进行培养,综合采用多种柱层析技术从Aspergillus sp.9H的次级代谢产物中分离得到了5个单体化合物,运用质谱、核磁等现代波谱技术鉴定其结构分别为brefeldin A(1),methoxyvermistatin(2),6-demethylvermistatin(3),purpurester A(4)和十一烷酸甘油酯(5)。其中化合物2,3,4均为首次从曲霉属海洋真菌中分离得到。  相似文献   

4.
为挖掘木榄内生真菌的降血糖功效,对木榄内生真菌Penicillium sp. GXIMD00006进行扩大培养,采用柱层析技术对其次级代谢产物进行分离纯化,利用NMR、MS等技术结合文献对比对分得的化合物进行鉴定。结果表明:共获得11个化合物,分别为:(+)-sclerotiorin (1)、 sclerotioramine (2)、 isochromophiloneⅧ(3)、 terretonin (4)、 terretonin A (5)、 chrodrimanin A (6)、 chrodrimanin B (7)、 chrodrimanin E (8)、 3,5-二羟基麦角甾醇-7,22-二烯-6-酮(9)、麦角甾醇(10)和过氧化麦角甾醇(11),其中,2个萜类衍生物4和5均为首次从青霉属中分离得到。该研究首次发现化合物1具有较强的α-葡萄糖苷酶抑制活性,IC50值为3.30μmol/L,表明木榄内生真菌的次级代谢产物具有开发成为新的α-葡萄糖苷酶抑制剂的潜力。  相似文献   

5.
采用硅胶柱层析、 ODS柱层析、 Sephadex LH-20以及半制备HPLC等方法,从广豆根内生真菌GDG-178(Fusarium equiseti)代谢产物中分离得到10个化合物,通过波谱分析,鉴定化合物的结构分别为:白僵菌素(1)、fusaproliferin (2)、11-epiterpestacin (3)、吲哚-3-乙酸(4)、indole-3-methylethanoate (5)、4-methyl-5,6-dihydro-2H-pyran-2-one (6)、柄曲霉素(7)、2′-hydroxydecanylpentadec-5,8,10,12-tetraneoate (8)、19-norergosta-5,7,9,22-tetraene-3β-ol (9)、对羟基苯甲醛(10)。其中,化合物7~10为首次从镰刀菌属Fusarium sp.中分离得到,化合物5和6为首次从木贼镰刀菌Fusarium equiseti中分离得到。  相似文献   

6.
为从Talaromyces属中分离获得更多生物活性显著的次级代谢产物,本文对一株药用红 树老鼠簕(Acanthus ilicifolius L.)来源真菌Talaromyces flavus TGGP35的次级代谢产物及其抗氧化 活性进行了研究。综合运用正相硅胶柱层析、Sephadex LH-20凝胶柱层析、半制备HPLC、薄层色 谱 TLC 等色谱分离方法,对该菌发酵产物乙酸乙酯粗浸膏部位进行系统分离纯化;综合利用 1DNMR、MS等波谱方法鉴定化合物的结构;采用抗氧化活性模型对化合物进行生物活性评价。从 内生真菌T. flavus TGGP35中分离得到7个单体化合物,分别为physcion(1),paeciloxanthone(2), 5-[(3E,5E)-3,5-nonadienyl]-1,3-benzenediol(3),trans-ferulic acid(4),3,4-二甲氧基甲苯 (5),对羟基苯甲醛(6)和对羟基苯乙酮(7)。从Talaromyces属真菌中分离鉴定了7个次级代谢产 物,抗氧化活性测试结果表明,化合物6具有显著的抗氧化活性,其IC50值为0.12 mmol/L,强于阳性 对照trolox(IC50值为0.23 mmol/L)  相似文献   

7.
Cytosporone B 的分离纯化,结构鉴定及其生物活性的初步研究   总被引:2,自引:0,他引:2  
从福建九龙江口红树林自然保护区桐花树树皮中分离出内生真菌HTF3菌株,用柱层析和正相HPLC的方法从该菌株的发酵液中纯化出一单体化合物,经ID-、2D-NMR和ESI-MS等方法鉴定该化合物为Cytosporone B.活性检测发现它具有较强的抗肿瘤活性和较广谱的抗真菌活性.本文报道这类物质有抗肿瘤活性.作用机理值得进一步深入研究。  相似文献   

8.
采用反复硅胶柱色谱法和Sephadex LH-20凝胶色谱法分离纯化南海红树林内生真菌Gx-3a的代谢产物,并通过理化常数测定和光谱分析鉴定其化学结构.结果从南海红树林内生真菌Gx-3a的菌体中分离得到4个代谢产物:ditryptophenaline(1),3-hydroxy-4-(2,6,6-trimethyl-tetrahydro-2 H-pyran-2-yl)benzoic acid (2),(E)-4,5-dihydroxy-3-(prop-1-enyl) cyclopent-2-enone(3),3,6-di-sec-butyl-1,4-dihy Droxypiperazine-2,5-dione(4),化合物1对口腔癌细胞KB,KBv200的抗肿瘤活性值分别为8.0和12.0 μmol/ml.4个化合物均首次从南海红树林内生真菌Gx-3a中分离得到.  相似文献   

9.
从广豆根内生真菌GDG-180中分离得到5个化合物,利用波谱技术确定其结构分别为麦角甾醇(1)、variecoxanthone A(2)、sydonic acid(3)、hydroxysydonic acid(4)、WIN64821(5)。其中,化合物2和4为首次从陆生真菌中分离得到,化合物3和5为首次从槐属植物内生真菌中分离得到。  相似文献   

10.
对烟台近岸的绿藻刺松藻来源的一株内生真菌长枝木霉的次生代谢产物进行了探索.通过硅胶柱层析、葡聚糖凝胶Sephadex LH-20柱层析、制备薄层层析和高效液相色谱等色谱分离手段,以及超导核磁共振等波谱鉴定技术,从该菌的马铃薯-葡萄糖和菊芋-葡萄糖液体培养基发酵产物中继续分离并鉴定了5个化合物,包括5α,8α-环氧麦角甾-6,22-二烯-3β-醇(1);麦角-7,22-二烯-3β,5α,6β-三醇(2);β-谷甾醇(3);5-羟基-3-甲基戊-2-烯酸(4)和角鲨烯(5).化合物4和5均为首次从木霉中分离得到.抑菌活性测试结果表明化合物1~5对细菌和真菌无明显抑制作用.  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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