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1.
苦豆草生物碱对松材线虫的抑制作用   总被引:6,自引:0,他引:6  
分别用槐果碱、苦参碱、槐胺碱、苦豆碱、野靛碱、N-甲基野靛碱、莱曼碱和总碱配制成生物碱浓度为1×10-4g/mL的PDA培养基,并在培养基上接种灰葡萄孢菌后再接种松材线虫,观察、记录松材线虫繁殖的情况。结果表明,苦豆碱、野靛碱和总碱对线虫的抑制繁殖作用都较强,其中,苦豆碱能完全抑制线虫的繁殖,且能引起线虫的死亡。对测定的生物碱的分子结构及对松材线虫的活性的分析进一步验证了关于双稠哌啶类生物碱对松材线虫的活性与其分子结构中的官能团对之间关系的假说。  相似文献   

2.
苦豆子生物碱抗菌活性的测定   总被引:2,自引:0,他引:2  
采用抑菌圈法测定了槐定碱、苦参碱、氧化苦参碱、氧化槐果碱、苦豆子总碱对大肠杆菌、金黄色葡萄球菌、枯草芽孢杆菌、番茄早疫、番茄灰霉和辣椒炭疽的抗菌活性。试验结果表明,5种生物碱对3种细菌生长均具有显著的抑制作用,其中槐定碱和苦参碱对大肠杆菌、枯草芽孢杆菌和番茄早疫的抗菌效果明显优于其他3种生物碱,苦参碱对大肠杆菌和枯草芽孢杆菌的最小抑菌浓度(MIC)达到12.5μg/mL。5种生物碱对3种真菌的抗菌效果弱于对3种细菌的抗菌效果,5种生物碱对3种真菌的MIC大于等于100μg/mL,氧化苦参碱、氧化槐果碱和苦豆子总碱对番茄灰霉菌的MIC均达400μg/mL。在质量浓度为100μg/mL时,5种生物碱中仅槐定碱表现出对辣椒炭疽菌的抑制作用。苦豆子总碱抗菌活性影响因素的试验结果表明,苦豆子总碱具有良好的热稳定性,在弱碱性条件下(pH 8左右)具有更好的抑菌活性,在至少12h内能够持续、稳定的对供试菌产生抑制作用。  相似文献   

3.
六种植物提取物对马尾松毛虫的抑食作用及毒性   总被引:15,自引:5,他引:15  
通过生物测定检验了合欢、木槿、皂荚、川楝、苦楝和苦豆草六种植物的提取物对马尾松毛虫的抑食作用和毒性。木槿和合欢的提取物对松毛虫取食无显著影响,也不具毒性。皂荚的乙醇提取物对松毛虫有抑食作用,但不具毒性。川楝、苦楝的石油醚提取物及川楝的乙醇提取物在较高浓度下抑制松毛虫的取食并对它们具毒性。苦豆草总生物碱的水溶部分对松毛虫有显著的抑食作用。水溶性生物碱、苦参碱、N-氧化苦参碱、槐定碱,野靛碱、苦豆碱均对松毛虫有不同程度的抑食作用和毒性。其中,N-氧化苦参碱和槐定碱表现出较强的抑食作用,槐定碱和苦豆碱对松毛虫表现出较高的毒性。  相似文献   

4.
从中药北豆根中提取北豆根生物碱.应用微量量热仪分别测定了不同浓度的北豆根生物碱对大肠杆菌、金黄色葡萄球菌、枯草杆菌代谢作用的热功率—时间曲线,运用Logistic方程计算出细菌的生长速率常数,建立了生长速率常数与药物浓度间的关系,进而确定了最佳抑菌浓度.北豆根生物碱对大肠杆菌、金黄色葡萄球菌、枯草杆菌的最佳抑菌浓度分别为0.7977mg/mL、0.2089mg/mL、0.1129mg/mL.通过对三个最佳抑菌浓度数据的比较,可知北豆根生物碱对三种细菌抑制效果为:枯草杆菌金黄色葡萄球菌大肠杆菌.  相似文献   

5.
采用生物测定的方法,选择苦参碱、槐啶碱、槐果碱、对羟基苯甲酸和阿魏酸5种物质,研究各物质水和丙酮溶液以及不同物质丙酮混合溶液对黄芪根腐病2种主要致病菌菌丝生长和孢子萌发的抑制活性和最低抑菌质量浓度.结果表明:不同物质对2种致病菌菌丝生长和孢子萌发的影响不同,同种物质丙酮溶液的抑菌效果明显好于水溶液的抑菌效果.3种生物碱对2种致病菌菌丝生长的抑制作用比较显著,其中槐啶碱丙酮溶液的抑菌活性最强,在质量浓度为1.00 g/L时的相对抑制率分别为43.63%,27.10%,最低抑菌质量浓度均为0.062 5 g/L.2种酚酸类物质对2种致病菌孢子萌发的抑制作用明显强于对菌丝生长的抑制作用.不同物质丙酮混合溶液对2种致病菌菌丝生长和孢子萌发的抑制活性与单个物质丙酮溶液无明显差异,抑制效果最好的槐啶碱和苦参碱混合液对2种致病菌抑制的EC50为31.62,10.00 g/L,最低抑菌质量浓度均为0.062 5 g/L.不同物质的水和丙酮溶液对2种致病菌活性的抑制作用存在明显的浓度效应,抑制作用随溶液浓度降低而减弱.  相似文献   

6.
凤尾草抗菌药物的提取与开发研究   总被引:1,自引:0,他引:1  
采用碱液提取凤尾草中的有效成分,确定了最佳提取方法;对提取物进行细菌和真菌的抑菌作用及最低抑菌浓度的研究结果表明该提取物对金黄色葡萄球菌、枯草杆菌、黑曲霉均有很强的抑菌效果,对大肠杆菌、青霉均有不同程度的抑菌效果,对黄曲霉基本上没有抑制作用.对金黄色葡萄球菌、枯草杆菌、黑曲霉的最低抑菌浓度(提取物g/100ml培养基)分别为0.59,0.72,0.78;对青霉、枯草杆菌的最低抑菌浓度(提取物g/100ml培养基)为0.98、1.05.  相似文献   

7.
凤尾草抗菌药物的提取与开发研究   总被引:12,自引:0,他引:12  
采用碱液提取凤尾草中的有效成分,确定了最佳提取方法;对提取物进行细菌和真菌的抑菌作用及最低抑菌浓度的研究结果表明;该提取物对金黄色葡萄球菌、枯草杆菌、黑曲霉均有很强的抑菌效果,对大肠杆菌、青酶均有不同程度的抑菌效果,对黄曲霉基本上没有抑制作用,对金黄色葡萄球菌,枯草杆菌、黑曲霉的最低抑菌浓度(提取物g/100ml培养基)分别为0.59,0.72,0.78;对青霉、枯草杆菌的最低抑菌浓度(提取物g/100ml培养基)为0.98、1.05。  相似文献   

8.
采用高效液相色谱法(HPLC)来测定新疆不同产地苦豆子种子中6种生物碱(金雀花碱、氧化苦参碱、N-甲基野靛碱、烟碱、槐定碱、苦参碱)的含量,并运用SPSS 22.0和SIMCA-P 14.1分析软件对不同产地样品中生物碱成分含量进行聚类分析和主成分分析。结果显示,不同产地苦豆子中金雀花碱、氧化苦参碱、槐定碱的含量存在差异,北疆产地的苦豆子种子中金雀花碱和槐定碱的含量普遍高于南疆。以上结果表明,所建HPLC法精密度、稳定性、准确度良好,可为完善苦豆子的质量控制标准提供参考。聚类分析和主成分分析方法可为苦豆子药材的道地性评估提供依据。  相似文献   

9.
印楝提取物及双稠哌啶类生物碱对桑天牛存活及生殖的影响   总被引:18,自引:2,他引:16  
用1.0μg/mm2剂量的黄华碱和野靛碱处理的构树枝分别喂饲桑天牛,黄华碱不表现拒食作用,但野靛碱表现出显著的拒食作用。同样剂量条件下,两种生物碱均能使桑天牛的产卵量和卵孵化率显著下降,但没有引起死亡。用8.0×10-2,4.0×10-2,2.0×10-2,1.0×10-2,5.0×10-3μg/mm2剂量的印楝提取物(含azadirachtin10%)处理的构树枝喂饲桑天牛,前二种剂量引起100%死亡率,2.0×10-2μg/mm2剂量引起80%死亡率并导致雌虫不再产卵,而后两种剂量引起的死亡率为30%和0%,并导致产卵量和卵孵化率较对照急剧地下降。报道了双稠哌啶类生物碱对昆虫引起产卵量和卵孵化率下降作用及天牛科中印楝提取物抑制产卵和卵孵化的作用。  相似文献   

10.
检测盐酸小檗碱和苦参碱联合氨苄西林对表皮葡萄球菌的抗菌作用.利用二倍稀释法、微量棋盘稀释法、时间-杀菌曲线评估法对8株临床分离的表皮葡萄球菌进行药物敏感性测定.结果表明,盐酸小檗碱、苦参碱、氨苄西林单药对表皮葡萄球菌的最小抑菌质量浓度分别为0.8~3.1μg/mL、12.5mg/mL和0.5~16.0μg/mL.盐酸小檗碱联合氨苄西林作用于8株分离株后,盐酸小檗碱和氨苄西林的最小抑菌质量浓度分别下降了88%~94%和75%,抑菌浓度指数为0.187~0.498;苦参碱联合氨苄西林作用于8株分离株后,苦参碱和氨苄西林的最小抑菌质量浓度分别下降了80%和75%~94%,抑菌质量浓度指数为0.188~0.450.2种生物碱联合氨苄西林作用于表皮葡萄球菌的时间-杀菌曲线显示,菌落减少量大于等于2lg N.盐酸小檗碱、苦参碱与氨苄西林联合作用表皮葡萄球菌均具有抗菌协同作用.  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.
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   

20.
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.  相似文献   

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