瘤状软骨凹顶藻化学成分研究   总被引：1，自引：0，他引：1  

苏华  朱校斌  袁兆慧  李敬  郭书举  韩丽君  史大永 《海洋科学》2009,33(5):33-35

采用硅胶柱色谱以及Sephadex LH-20凝胶色谱手段,对海洋红藻瘤状软骨凹顶藻(Chondrophycus papillous Garbary et Harper)进行化学成分研究,分离得到5个化合物.通过MS、NMR等方法对得到的化合物进行结构确证,分别鉴定为邻苯二甲酸二丁酯(Ⅰ),邻苯二甲酸二异辛酯(Ⅱ),胆甾醇(Ⅲ),植醇(Ⅳ)和4-羟基苯甲醛(Ⅴ).所有化合物均为首次从该种海藻中分离得到.通过MTT法对得到的单体化合物进行细胞毒活性筛选,结果显示所有化合物在10 mg/L浓度下均无明显活性.  相似文献   

Chemical constituents of marine medicinal mangrove plant Sonneratia caseolaris     

TIAN Minqing  DAI Haofu  LI Xiaoming  WANG Bingui 《中国海洋湖沼学报》2009,27(2)

Twenty-four compounds including eight steroids (1-8), nine triterpenoids (9-16, 24), three flavonoids (20-22), and four benzenecarboxylic derivatives (17-19, 23) were isolated and identified from stems and twigs of medicinal mangrove plant Sonneratia caseolaris. The structures of the isolated compounds were determined by extensive analysis of their spectroscopic data. Among these metabolites, compounds 1, 4-20 and 22-24 were isolated and identified for the f'urst time from S. caseolaris. In the in vitro cytotoxic assay against SMMC-7721 human hepatoma cells, compound 21 (3',4',5,7-tetrahydroxyflavone)exhibited significant activity with IC50 2.8 μg/mL, while oleanolic acid (14), 3,3'-di-O-methyl ether ellagic acid (18), and 3,3',4-O-tri-O-methyl ether ellagic acid (19) showed weak activity. None of these compounds displayed significant antibacterial activites.  相似文献   

White spot syndrome virus envelope protein VP124 involved in the virus infection     

ZHU Yanbing  WU Chenglin  YANG Feng 《海洋学报(英文版)》2008,27(4):130-136

White spot syndrome virus （WSSV） is one of the major shrimp pathogens causing large economic losses to shrimp farming. In an attempt to identify the envelope proteins involved in the virus infection, purified WSSV virions were mixed with three antisera against WSSV envelope proteins （VP39, VP124 and VP187 ）, individually. And then they were injected intramuscularly into crayfish （Procambarus clarkii） to conduct in vivo neutralization assays. The results showed that for groups injected with virions only and groups injected with the mixture of virions and antiserum against VP124, the crayfish mortalities were 100% and 60% on the 8th day postinfection, individually. The virus infection could be delayed or neutralized by antibody against the envelope protein VP124. Quantitative PCR was used to further investigate the influence of three antisera described above on the virus infection. The results showed that the antiserum against VP124 could restrain the propagation of WSSV in crayfish. All of the results suggested that the viral envelope protein VP124 played a role in WSSV infection.  相似文献   

分析技术在海洋浮游生物铁载体研究中的应用     

王颜萍  何鹰  郑晓玲  陈发荣  黎先春  王小如 《海洋科学进展》2005,23(2):227-233

铁对海洋浮游植物的生长起着重要的作用。在高营养盐低叶绿素(HNLC)海区，铁是藻类生长的限制因子；而在近岸，铁又是赤潮发生的激发因子之一。研究表明，可溶性铁对浮游植物生长有很强的控制作用，大部分可溶性铁是同具有极强铁亲和力的配位体螯合在一起的，如铁载体。因此，在对铁限制、铁加富实验的研究中，铁载体的提取与分析技术显得尤为重要。着重介绍了海洋浮游植物中铁载体的提取及检测分析技术。  相似文献   

DNA adducts in mussels and fish exposed to bulky genotoxic compounds     

Dolcetti L  Zuanna LD  Venier P 《Marine environmental research》2002,54(3-5):481-486

Biological and procedural factors can influence DNA adduct detection in aquatic organisms. Among them, functional structure and metabolic traits represent major biological determinants for adducts formed by lipophilic pro-mutagenic contaminants. In detecting DNA adducts through the 32P-postlabelling assay, efficiency in DNA purification, digestion, labelling, as well as adduct enrichment and quantification may explain differences between independent studies. Reference DNA adducts have been used to verify some 32P-postlabelling aspects. Data obtained for mussels and fish treated with benzo[a]pyrene (B[a]P) and environmentally exposed to genotoxins confirm the above assertions. Although the 32P-postlabelling assay cannot be proposed for routine biomonitoring it appears a reliable and very sensitive index of exposure to genotoxic pollutants in both fish and mollusks.  相似文献   

应用硫酸苯酚法建立一种甘露糖醛酸C-5差向异构酶活性检测方法的研究          下载免费PDF全文

林育姿  宫倩红  张真庆  韩?? 峰  于文功 《海洋科学》2007,31(2):48-51

建立了一种简便快捷的甘露糖醛酸C-5差向异构酶活性的测定方法。研究发现相同分子质量的聚甘露糖醛酸和聚古罗糖醛酸与苯酚硫酸试剂反应后显色程度不同,以此可以用来测定β-D-甘露糖醛酸/α-L-古罗糖醛酸(M/G)值的变化,从而计算甘露糖醛酸C-5差向异构酶的活性。利用本方法测定了已知结构的褐藻胶片断的M/G比,其结果与传统的1H-NMR测定值基本一致。  相似文献   

Assessing DNA damage in cnidarians using the Comet assay     

Mitchelmore CL  Hyatt S 《Marine environmental research》2004,58(2-5):707-711

The assessment of DNA damage by the Comet assay has been described as a useful non-specific general biomarker of stress in many marine organisms. In field situations it has successfully been employed to distinguish between reference and polluted sites and in the laboratory it has been widely used as a mechanistic tool to determine pollutant effects and mechanisms of DNA damage. To date a wide range of marine vertebrates and invertebrates have been used, however, the usefulness of this assay as a biomarker in cnidarians has not yet been assessed. The aims of this study were to optimize the Comet assay for cnidarian cells and to assess its utility for detecting genotoxic damage in these cells. Cells were isolated from the North American pacific coast temperate sea anemone Anthopleura elegantissima using a non-enzymatic dissociation procedure and viability was determined to be in excess of 90%. Cells were incubated either with (1 h acute exposures) hydrogen peroxide (H(2)O(2)), ethylmethanesulphonate (EMS) or benzo(a)pyrene (B[a]P). In comparison to other marine species, anemone cells exhibited high control or background levels of DNA strand breaks. Despite this, however, we observed dose responses for each of the study chemicals with no reduction in cell viability. This study demonstrates that anemone cells respond to known DNA damaging agents, including B[a]P which requires metabolism to exert its genotoxic effect, and that the Comet assay may prove to be a useful biomarker of stress in cnidarian species.  相似文献   

Periodicity in the crater formation rate and implications for astronomical modeling     

S. Yabushita 《Celestial Mechanics and Dynamical Astronomy》1992,54(1-3):161-178

Claim for periodicity in the crater formation rate is reinvestigated using a criterion proposed by Broadbent, and data sets of Rampino and Stothers and of Grieve are shown to satisfy the periodicity criterion (P 30 Myr).On the other hand, currently observed impactors are mainly asteroids, while long and short periodic comets whose fluxes may vary by external disturbances occupy only a small fraction. Using a Monte Carlo simulation, constraints are obtained for the dispersion Q(Myr) from an exact periodicity and for the periodic components (F _tp) in the signals for their periodicity to be detected. It is found that for = 5, 6 and 7 Myr, F _tp, would have to be 40% or greater, 60% or greater and 80% or greater, respectively. These constraints are used to discuss whether the giant molecular cloud perturbations can give rise to the periodicity in the impact events. The amplitude of the solar Z-motion need to be some 100pc for = 6 Myr, which requires the periodic component (SP and LP comets, if the former originate from the latter) to be 60%, while for = 7 Myr, the periodic component need to be 80%. The GMC perturbation model consistent with the periodicity appears to be the one where the amplitude is 100pc and the periodic component - 60% of the impactors. If SP comets mainly originate from a source such as the hypothetical Kuiper belt, the GMC perturbation would not be consistent with the periodicity.  相似文献   

A model of the galactic tidal interaction with the oort comet cloud     

John J. Matese  Patrick G. Whitman 《Celestial Mechanics and Dynamical Astronomy》1992,54(1-3):13-35

We consider a model of the in situ Oort cloud which is isotropic with a random distrihution of perihelia directions and angular momenta. The energy distribution adopted has a continuous range of values appropriate for long-period (>200 yr) comets. Only the tidal torque of the Galaxy is included as a perturbation of comet orbits and it is approximated to be that due to a quasi-steady state distribution of matter with disk-like symmetry. The time evolution of all orbital elements can be analytically obtained for this case. In particular, the change in the perihelion distance per orbit and its dependence on other orbital elements is readily found. We further make the assumption that a comet whose perihelion distance was beyond 15 AU during its last passage through the Solar System would have orbit parameters that are essentially unchanged by planetary perturbations. Conversely, if the prior passage was inside 15 AU we assume that planetary perturbations would have removed the comet from the in situ energy distribution accessible by the galactic tide. Comets which had their perihelia changed from beyond 15 AU to within 5 AU in a single orbit are taken to be observable. We are able to track the evolution of 10⁶ comets as they are made observable by the galactic tidal touque. Detailed results are obtained for the predicted distribution of new (0 < 1/ < 10^–4 AU^–1) comets. Further, correlations between orbital elements can be studied. We present predictions of observed distributions and compare them with the random in situ results as well as with the actual observed distributions of class I comets. The predictions are in reasonable agreement with actual observations and, in many cases, are significantly different from random when perihelia directions are separated into galactic northern and southern hemispheres. However the well-known asymmetry in the north-south populations of perihelia remains to be explained. Such an asymmetry is consistent with the dominance of tidal torques today if a major stochastic event produced it in the past since tidal torques are unable to cause the migration of perihelia across the latitude barriers ±26°.6 in the disk model.  相似文献   

Development of a fluorescence quenching assay to measure the fraction of organic carbon present in self-assembled gels in seawater     

Yong-Xue Ding  Wei-Chun Chin  Pedro Verdugo   《Marine Chemistry》2007,106(3-4):456-462

The dissolved organic carbon pool (DOC) is among the largest reservoir of reduced carbon on our planet. The demonstration that DOC polymers remain in assembly/dispersion equilibrium forming microscopic hydrogels has a broad range of critical implications. Previous studies estimate that  10% of DOC could be assembled as gels, yielding values of  7 × 10¹⁶ g of organic carbon present as microscopic hotspots of high substrate concentration. This huge mass of reduced carbon emphasizes the need to develop reliable methods to systematically investigate the budget of self-assembled marine gels (SAG), and their role in biogeochemical cycling. However, a quantitative method to measure SAG in seawater has not been available. Here we present the validation of a simple assay to measure the mass of organic carbon assembled as microgels in native seawater. This method is based on the ratio of Chlortetracycline (CTC) fluorescence quenching between Ca bound to non-assembled organic molecules and molecules assembled as microgels. This assay can be readily implemented on board using a low cost fluorometer and provisions to measure TOC.  相似文献