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克雷伯氏菌和伯克霍尔德氏菌复合菌群催化三硝基甲苯降解 总被引:1,自引:0,他引:1
通过摇瓶实验研究了克雷伯氏菌 (S1) 和伯克霍尔德氏菌 (S2) 复合菌群 (简称 S) 降解三硝基甲苯 (TNT) 的特性和机理. 结果表明, 在外加碳源和氮源时, 100 mg/L TNT 在 16 h 内可被菌群 S 完全去除. 只外加碳源时, TNT 的最高去除率为 80%; 只加入氮源时, 仍可除去 12% 的 TNT. 在 S1 催化体系中检测到较高活性硝基还原酶的存在, 该酶催化 TNT 转化为缩合中间产物二硝基双偶氮甲苯, 其分子量为 326. 但是只有 S1 和 S2 共存才能产生高活性的甲苯双加氧酶和邻苯二酚 2,3-双加氧酶, 两类酶共同催化中间产物的开环分解. 伴随着二硝基双偶氮甲苯的开环分解, 硝基脱落生成 NO2–, 后者进一步氧化生成 NO3–. 通过 S1 和 S2 的协同作用, 实现了 TNT 的好氧开环和硝基脱落, 该结果表明在 TNT 生物催化降解中复合菌群比单一菌株更具优势和潜力. 相似文献
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Marine sponges are one of the prolific producers of bioactive natural products with therapeutic potential. As an important subgenus of Haliclona, Reniera sponges are mainly distributed in the Mediterranean Sea and Atlantic area, and had been chemically investigated for over four decades. By an extensive literature search, this review first makes a comprehensive summary of all natural products from Reniera sponges and their endozoic microbes, as well as biological properties. Perspectives on strengthening the chemical study of Reniera sponges for new drug-lead discovery are provided in this work. 相似文献
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式根岛海绵及其高度复杂的共生体系是生物活性物质的丰富重要来源, 产生以calyculins为主要成分的毒性物质. 活性物质含量低, 使得直接从海绵分离大量活性物质不可取. 海绵共生菌是活性物质的主要生产者, 但是大部分的共生菌是不可培养的, 使得单纯的分离培养不能发挥很好的作用. 功能宏基因组学避开了培养的瓶颈, 可以获取独特的活性物质及其功能基因. 对式根岛海绵2013年2月以前分离出的活性物质作一综述, 并对非培养依赖型的功能宏基因组学, 在蕴含大量不可培养微生物的式根岛海绵中的应用进行综述. 探讨功能宏基因组在研究开发式根岛海绵及其他海绵的活性物质及有趣功能基因中的应用潜能, 为研究国内海绵的丰富活性物质和有趣的基因提供一种思路和方法. 相似文献
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海绵Phacelliafusca中含氮化合物的分离与结构鉴定 总被引:1,自引:0,他引:1
从采自中国南海西沙群岛海域的海绵Phacellia fusca Schmidt中得到4个含氮 化合物。经~1H NMR,~(13)C NMR,HMQC,HMBC,~1H-~1HCOSY,FABMS和EIMS等光谱分析 ,确证其结构分别为:N,N'-二[2-乙氧基-1(Z)-乙烯基]脲(1),2- Bromoaldisin(2),Aldisin(3)Dibromophakellin盐酸盐(4)。其中化合物1为一具有 对称结构的新脲类化合物,命名Phacelliaurea A;化合物4是首次从该海绵中分离 得到的已知胍基生物碱,首次报到了它的~(13)C NMR数据及其归属。 相似文献
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Sterols are essential components of all eukaryotic cells and were the first group of marine sponge natural products used in the taxonomic characterization of marine sponges. Thus, in the past decade there has been an increasing interest in sterols of marine sponge, which has led to the discovery of a large number of novel compounds. The use of a variety of separation techniques has demonstrated the complexity of the sterol components of marine extracts, up to 50 sterols from one species of organism. However, the quantity of each sterol 相似文献
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建立了一种用于水体中副溶血弧菌、河弧菌和大肠杆菌检测定量的蛋白微阵列免疫分析法。以Cy3标记免疫球蛋白(IgG)为探针,蛋白芯片为载体,对孵育反应的IgG浓度、反应时间和温度等条件进行了优化,结果表明:当IgG浓度为0.1g/L在37℃下孵育60min,可以获得理想的检测效果;在优化条件下,本方法中副溶血弧菌、河弧菌和大肠杆菌的检出限分别为9.9×104个/mL、9.3×104个/mL和3.9×105个/mL;将本方法与ELISA进行了比较,结果表明,本方法具有快速、操作便捷、高通量检测等特点;并将本方法应用于海水中这3种致病菌的快速、准确地定量检测。 相似文献
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设计高性能的可压缩电极是实现可压缩电容器器件的关键,碳海绵(CS)具有理想的压缩形变,但却受制于有限的容量。本工作以CS为可压缩基底,通过恒电流沉积及低温热处理技术,在CS骨架上均匀沉积了α-Fe_2O_3纳米片。复合电极中Fe_2O_3的负载量随沉积时间的延长逐渐增加,且在沉积16 h后达到饱和。系统地考察了CS-Fe_2O_3复合电极在不同压力下的可压缩性能,并在三电极体系中,通过循环伏安、恒电流充放电等方法研究了CS-Fe_2O_3复合电极在3.0mol·L~(-1)KOH电解液中的电容性能。结果表明,当复合电极CS-Fe_2O_3压缩率减小时,电极的内阻增大,比电容相应减小。CSFe_2O_3-12电极在电流密度为1 A·g~(-1)时的最大比电容为294 F·g~(-1),且经过10000次恒电流充放电后,电容量仍然能保持初始值的81%,是一种潜在的电化学性能稳定的可压缩超级电容器电极材料。 相似文献
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构建了式根岛海绵的宏基因组文库,对其进行双层琼脂抗菌活性功能筛选,得到1株抗菌活性克隆pDC111. 以抗菌活性为指导,对pDC111的化学成分进行分析和分离,得到化合物1,并通过1D NMR(1H NMR和 13C NMR)及2D NMR(1H-1H COSY,HMQC和HMBC)结合HR-TOFMS数据,确定其结构为吲哚三聚体. 抗菌活性实验结果表明,化合物1在10 μg/paper(id=6 mm)时,对蜡状芽孢杆菌的抑菌圈达到12 mm. 本文利用功能宏基因组方法,从蕴藏大量不可培养微生物的海绵中寻找到活性物,并具有通过分子生物学技术获得其功能基因的潜能. 相似文献
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《Analytical letters》2012,45(6):299-306
Abstract A method for the determination of pyrene, fluoranthrene and phenanthrene in the “anthracene oil” residue, after removal of anthracene, is described utilizing measurements of absorbance at three wavelengths in the ultraviolet and solution of the three simultaneous equations produced. Molar absorptivities for the three hydrocarbons are given and the accuracy of the determination is discussed. 相似文献
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芘和蒽作为荧光探针探测树枝形聚合物微环境 总被引:2,自引:0,他引:2
分别以芘和(9-蒽基)甲基三甲基溴化铵(An)作为荧光探针研究了一系列羧基为外围末端基团的芳醚树枝形聚合物Gn(n=1-4)的内部微环境极性及包结情况. 芘荧光I1/I3值在1-3代树枝形聚合物钾盐水溶液中变化不大, 而3到4代有一个陡降, 推测1-3代树枝形聚合物处于相对开放的结构, G4为相对密闭的球形结构, 4代树枝形聚合物表现出更好的包结特性. An在树枝形聚合物G2钾盐水溶液中的荧光光谱结果表明, 树枝形聚合物G2可以包结两个以上的An分子, An分子疏水的蒽环部分位于树枝形聚合物内部孔穴中, 而带正电荷的铵离子靠近树枝形聚合物分子的极性末端. 相似文献
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6-Phenyl-2,2‘-bipyridine linked pyrene and anthracene were synthesized and their photophysical properties were measured in different solvents with different polarity. 4-Pyren-1““-yl-6-phenyl-2,2‘-bipyridine (Ppbpy) showed significant solvent-dependent properities while 4-anthracen-yl-9““-yl-6-phenyl-2,2‘-bipyridine (Apbpy) displayed solvent-independence, although they had similar molecular structure. Because of different twist angle between thyarene and aryl-bipyridine, Ppbpy displayed intermixing behaviors of local excited state (^1La and ^1Lb) and intramolecular charge transfer (ICT), but Apbpy only showed the properties of local excited state ^1La. 相似文献
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A natural proline‐rich tetrapeptide cyclo‐prolyl‐leucyl‐prolyl‐phenylalanyl was prepared employing solution‐phase method of peptide synthesis through coupling of dipeptide fragments Boc‐l‐Pro‐l‐Leu‐OH and l‐Pro‐l‐Phe‐OMe which utilizes diisopropylcarbodiimide (DIPC) as coupling agent and N‐methylmorpholine (NMM) as the base. Deprotection of linear tetrapeptide unit followed by its cyclization provided a cyclopeptide, identical in all aspects to the natural molecule. Pharmacological evaluation showed cytotoxic, antifungal and antihelmintic potential of synthesized peptide against Dalton's Lymphoma Ascites (DLA) and Ehrlich's Ascites Carcinoma (EAC) cell lines, pathogenic dermatophytes and earthworms. 相似文献
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Natchanun Sirimangkalakitti Kazuo Harada Makito Yamada Masayoshi Arai Mitsuhiro Arisawa 《Molecules (Basel, Switzerland)》2023,28(1)
Chemical diversification of substances present in natural product extracts can lead to a number of natural product-like compounds with a better chance of desirable bioactivities. The aim of this work was to discover unprecedented chemical conversion and produce new compounds through a one-step reaction of substances present in the extracts of marine sponges. In this report, a new unnatural tetracyclic bromopyrrole-imidazole derivative, rac-6-OEt-cylindradine A (1), was created from a chemically diversified extract of the sponge Petrosia (Strongylophora) sp. We also confirmed that 1 originated from naturally occurring (-)-cylindradine A (2) via a new reaction pattern. Moreover, (-)-dibromophakellin (3) and 4,5-dibromopyrrole-2-carboxylic acid (4), as well as 2, were reported herein for the first time in this genus. Studies on the possible reaction mechanism and bioactivities were also conducted. The results indicate that the direct chemical diversification of substances present in natural product extracts can be a speedy and useful strategy for the discovery of new compounds. 相似文献
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利用光热材料的太阳能水蒸发技术是一种绿色、 环保地解决淡水资源短缺的重要技术, 但光热材料的制备成本、 蒸发效率和热损失等因素限制了其推广应用. 本文采用一锅法制备了聚乙烯醇载银海绵(AgNPs/PVA)太阳能界面蒸发器, 并研究了AgNPs含量对AgNPs/PVA在太阳能驱动水蒸发过程中光热性能的影响. 研究结果表明, 当AgNPs的质量为PVA的10%时, 制备的AgNPs/PVA在1 kW/m 2的太阳光强度下具有最优的蒸发速率, 水蒸发速率可达1.62 kg?m ?2?h ?1, 为纯水(0.42 kg?m ?2?h ?1)的3.9倍. 本文制备的AgNPs/PVA具有制备工艺简单、 亲水性能优良和蒸发性能良好的特点, 在太阳能驱动水蒸发领域具有较大的应用前景. 相似文献
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恒能量同步荧光法[’j是同步荧光洁的一个新分支.该法在激发和发射波长的同时扫描过程中,可保持两者之间的一个恒定的能量差关系.苟、危、惠和完均属多环芳烃(PHAS),其振动能层间隔在1400~1600cm‘之间.采用固定能量差凸9一1600cm-’,对4种物质的混合体系进行恒能量同步荧光法测定,可简化谱图,达到混合物体系各组分同时测定的目的.导数技术能放大窄带的灵敏度,对恒能量同步荧光光谱的窄带应用很有利[’j.两者联用可使检测限更低,对各组分的分辨更有效”‘,采用一阶导数一恒能量同步荧光法对药、危、意和芬的检出限依次… 相似文献