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1.
滨海湿地耐盐植物二色补血草化学成分研究 总被引：5，自引：0，他引：5
采用硅胶柱层析,Sephedex-LH-20凝胶层析,HPLC等方法,从滨海湿地耐盐植物二色补血草中分离得到了10个单体化合物。运用NMR,MS以及与文献对照,鉴定它们的结构分别为豆甾烷-3,6-二酮(1),豆甾-4烯-3,6-二酮(2),6β-羟基-豆甾-4-烯-3-酮(3),5α,8α-环二氧-24-甲基-胆-甾6,22E-二烯-3β-醇(4),5,α8α-环二氧-24-甲基-胆甾-6,9,22E-三烯-3β-醇(5),麦角-甾4,6,8(14),22E?四烯-3-酮(6),植醇(7),正十六烷酸(8),亚油酸(9),亚油酸单甘油酯(10)。化合物1~7和10为首次从该植物中分离得到。 相似文献
2.
对采自广西涠州岛近海多管藻(Poiysiphonia urceolata)分离到的一株内生真菌EN-22的次生代谢产物的化学成分进行了研究.利用正相硅胶柱层析、葡聚糖凝胶Sephadex LH-20柱层析、制备薄层层析(PTLC)以及重结晶等分离手段从该菌发酵液中分离得到15个化合物,通过一维、二维核磁共振技术、质谱技术等鉴定了所有化合物的结构,分别为:4-(4-喹啉)-4-羟基-2-丁酮(1),3-羟基-3-(2-氧丙基)吲哚-2-酮(2),3-吲哚乙醇(3),3-吲哚甲酸(4),2-羟基-3-吲哚丙酸(5),2-酮-3-吲哚乙醇(6),3,3-二吲哚-2-羟基-丙醇(7),β-咔啉(8),尿嘧啶(9),环-(S-脯氨酸-S-异亮氨酸)(10),(22E,24R)-3β,5α,9α-三羟基麦角甾-7,22-二烯-6-酮(11),(22E,24R)-5α,6α-环氧麦角甾-8,22-二烯-3β,7α-二醇(12),5α,6α-环氧-24(R)-甲基胆甾-7,22-二烯-3β-醇(13),胡萝卜苷(14),过氧化麦角甾醇(15);其中化合物1和2为新天然产物,并首次报道化合物1的碳谱数据. 相似文献
3.
从南海圆裂短足软珊瑚(Cladiella krempfi)中分离出12个甾体化合物,分别鉴定为:1,2-[1',3',4']oxodithiin-pregna-20-en-3-one(1);19-nor-4-methylpregna-1,3,5(10),20-tetraen-1-ol(2);pregna-1-en-3-one-20-ol(3);pregna-1,7-dien-20-ol-3-one(4);pregna-5,20-dien-3-O-α-fucopyranoside(5);pregna-20-en-3-O-α-fu-copyranoiside(6);孕甾-1,20-二烯-3-酮(7);孕甾-1,4,20-三烯-3-酮(8);24-甲基-5α-胆甾-7,22-二烯-3β,5,6β-三醇(9);26-甲基-24-亚甲基胆甾-5烯-3β-醇(10);胆甾-5-烯-3β醇(11);β-谷甾醇(12).化合物1～6系首次从Cladiella属软珊瑚中获得的孕甾类化合物.对所获得化合物的生源途径进行了初步讨论. 相似文献
4.
应用色谱－质谱（GC－MS）方法分别鉴定了从广西海涠洲岛水域和海南省陵水县水域采集的莳萝曲网海绵Sigmadocia cymiformis的甾醇类化合物,涠洲岛水域的莳萝曲网海绵所含的旮醇类化合物主要是：胆甾－4，6－二烯3β－醇（1），27－降麦角甾5，22－二烯－3β－醇，（2），胆甾醇（3），（24S）－麦角甾5，22－二烯3β－醇（40，麦角甾5－烯C－3β－醇（5），麦角甾－2，22－二烯－3β－醇（6），豆甾醇（7），β－谷甾醇（8），麦角甾－4，24（28）－二烯－3－酮（9），柳珊瑚甾醇（10）；而陵水县水域的莳萝曲网海绵所含甾醇类化合物主要是：（3），（4），（5），（6），（8），胆甾－2，55－二烯－3β－醇（11），胆旨－3，5－二烯－7－酮（12），这是莳萝曲网海绵中甾醇类化合物组成的首次报道。 相似文献
5.
综合运用正相和反相硅胶柱层析、Sephadex LH-20凝胶柱层析以及制备HPLC等分离方法,从1种中国南海海绵Xestospongia testudinaria中追踪分离抗肿瘤活性次级代谢产物。从95%乙醇提取物中分离获得8个单体化合物,通过NMR,MS等波谱技术鉴定其结构分别为:E-18,18-二溴-9,17-二烯-5,7-二炔硬脂酸甲酯(1),E-18,18-二溴-9,17-二烯-5,7-二炔硬脂酸乙酯(2),麦角甾-5,7,22-三烯-3-醇(3),麦角甾-4,6,8(14),22-四烯-3-酮(4),胆甾-4-烯-3-酮(5),3-吲哚醛(6),3-吲哚酸(7)和5-吲哚醛(8)。其中,化合物2-5和8为首次从该属海绵中分离得到。化合物1对肿瘤细胞株HCT116和A549显示较强的抑制活性。 相似文献
6.
本实验采用群体感应抑制(quorum sensing inhibitory, QSI)活性导向法, 对分离自山东威海近海底泥的真菌WH7-2开展代谢产物研究。综合菌落形态和转录间隔区 (Internal Transcribed Spacer, ITS)全序列分析, 菌株WH7-2鉴定为腐皮镰刀菌Fusarium solani。综合运用多种色谱方法, 从该真菌大米发酵产物的活性部位中分离得到11个化合物。分别鉴定为 (2E, 5E)-3, 5, 7-三甲基-2, 5-辛二烯酸 (1)、不饱和脂肪酸酯混合物 (2—4)、镰红菌素-3-甲醚 (5)、脱水镰红菌素 (6)、(22E)-5α, 8α-过氧化麦角甾-6, 22-二烯-3β-醇(7)、(22E)-5α, 8α-过氧化麦角甾-6, 9 (11), 22-三烯-3β-醇(8)、3β-羟基-胆甾-5-烯-7-酮 (9)、6β-羟基-胆甾-4-烯-3-酮 (10)和(22E)-胆甾-5, 22-二烯-3β-醇 (11)。其中不饱和脂肪酸酯混合物(2—4)具有QSI活性, 其他化合物无QSI活性。除5和6外, 其他化合物均为首次从腐皮镰刀菌F. solani中发现。 相似文献
7.
对采自海南文昌红树林根际土壤样品中分离到的真菌Penicillium sp. MA-37的次生代谢产物的化学成分进行了研究.利用硅胶柱层析、葡聚糖凝胶Sephadex LH-20柱层析、制备薄层层析以及重结晶等分离方法并通过现代波谱技术共分离、鉴定了8个天然产物,分别为:氮-(2-甲氧基-4-羟基苯)-丙酰胺酸(1),氮-(2,4-二甲氧基苯)-丙酰胺酸(2),氮-(2,4-二甲氧基苯)-丙酰胺酸甲酯(3),(22E,24R)-麦角甾-5,7,22-三烯-3β-醇(4),(22E,24R)-麦角甾-4,6,8(14),22-四烯-3-酮(5),(22E,24R)-5α,8α-环二氧麦角甾-6,22-双烯-3β-醇(6), asperamide B (7), cis-4-hydroxy-6-deoxyscytalone (8);其中化合物1为新化合物,化合物2和3为新天然产物. 相似文献
8.
柄海鞘Styela clava中的甾醇化合物的分离和鉴定 总被引：2，自引：0，他引：2
应用GC-MS技术从青岛海域产柄海鞘Styela
clava中分离鉴定出5种甾醇化合物,分别是(22Z)-26,27-二降-麦角甾-5,22-二烯-3β-醇(1),胆甾-5,22-二稀-3β-醇(2),胆甾醇(3),胆甾烷醇(4),(22E)-麦角甾-5,22-二烯-3β-醇(5)。 相似文献
9.
从南海小月柳珊瑚Menella sp.石油醚萃取部位中分离得到7个孕甾烷类化合物,通过波谱分析并与文献对照,其结构分别鉴定为3a-羟基-5β-孕甾-20-酮(1),3β-羟基-5a-孕甾-20-酮(2),3β-羟基-孕甾-5-烯-20-酮(3),5β-孕甾-3,20-二酮(4),5a-孕甾-3,20-二酮(5),孕甾-4-烯-3,20-二酮(6),孕甾-1,4-二烯-3,20-二酮(7);除化合物2外其他化合物都为首次从该属柳珊瑚中分离得到,其中化合物7是首次报道其核磁数据. 相似文献
10.
从采自大连近海的红藻鸭毛藻（Symphyocladia latiuscula）中分离到一株肉座菌目真菌（Hypocreales sp．），对其发酵代谢产物的化学成分进行了研究。利用正相硅胶柱层析、葡聚糖凝胶Sephadex LH-20柱层析、制备薄层层析（PTLC）以及重结晶等分离手段，并通过一维、二维核磁共振技术、质谱技术等从该菌发酵液中分离鉴定了10个化舍物：双酚A（1）；邻羟基苯甲酸（2）；吲哚甲酸（3）；吲哚乙酸（4）；N-乙酰色胺（5）；（22E，24R）-麦角甾-7，9，22三烯-3β-醇（6）；过氧化麦角甾醇（7）；（22E，24R）-5α，6α-环氧麦角甾-8，22-二烯-3β，7α-二醇（8）；（22E，24R）-麦角甾-7，22-二烯-6β-甲氧基-3β，5α-二醇（9）；啤酒甾醇（10）。这些化合物均为首次从该菌中分离得到，其中化合物1为首次作为天然产物分离得到。 相似文献
11.
Arne Schnack-Friedrichsen Angela M. Davis Jim D. Bennell Dei G. Huws 《Marine Georesources & Geotechnology》2001,19(4):221-243
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths. 相似文献
12.
Shigehisa Nakamura 《Marine Geodesy》2000,23(1):55-61
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone. 相似文献
13.
The effect of different fixation and storage protocols on the flow cytometric (FCM) simultaneous analysis of bacterioplankton and phytoplankton in coastal seawater samples (Mediterranean coastal lagoons) was investigated. FCM measurements (cell number, fluorescence and scatter characteristics) were obtained through DAPI staining. Three fixatives [glutaraldehyde (GA), formaldehyde (FA) and paraformaldehyde (PFA)] and two storage (3 months duration) methods (5 °C and −196 °C) were tested. Two dominant populations were detected in studied samples: bacteria and eukaryotic picophytoplankton. Adding fixatives (2% final concentration) appears necessary to obtain FCM exhaustive counts of all the bacteria and phytoplanktonic cells. This was related to the permeation effect of fixatives which allowed a better DAPI staining of the cells. Maximum fluorescence, i.e. optimal staining of the cells was obtained with FA or PFA, and significant lower fluorescences with GA. Fixed samples stored at 5 °C induced rapid cell loss. Only storage in liquid nitrogen of samples fixed with FA or PFA, allows mid-term (≥4 months) preservation of bacteria or picophytoplankton cell numbers, and limited evolution of DAPI-induced fluorescence and scatter characteristics. 相似文献
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15.
《海洋学报(英文版)》2014,(9):F0003-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology, 相似文献
16.
The relationship between the flux of exotic benthic foraminiferal tests (i.e. tests which are supplied from open-sea sources alone) in a tidal inlet and that of bulk sediment was analysed, which can be expressed as two first-order linear equations. According to this relationship, in order to determine net sediment transport directions in the entrance, the test concentration in surficial sediments of the tidal basin can be compared against a ‘ critical level ’. The critical level is determined for the conditions that no net transport of bulk sediment is present within the entrance. If the observed concentration (averaged over the tidal basin) is higher than the simulated critical level, then the net sediment transport is directed to landward. This method is applied to the analysis of net sand transport at Christchurch Harbour, a tidal inlet system located in southern England. In this investigation, concentrations of exotic foraminiferal tests in the surficial sediments of the tidal basin and ebb tidal delta area were obtained from the analysis of sea-bed sediment samples. A series of probable critical levels were calculated based upon the data sets with regard to: (1) sediment discharge from the rivers; (2) magnitude of sediment discharge within the entrance during the ebb; (3) the test concentration outside the harbour; (4) the thickness of the moving layer; and (5) two parameters associated with dispersive processes. The results show that the concentration in the tidal basin sediment is higher than a number of simulated critical concentrations for representative cases. Consequently, the high level of the concentration of exotic benthic foraminiferal tests within the harbour should be explained as a result of landward net transport of sands within the entrance. 相似文献
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18.
Rahul Sharma 《Marine Georesources & Geotechnology》2000,18(3):237-250
Observations on seafloor features from subbottom profiling and seabed photography data show that the undisturbed and natural conditions before the benthic disturbance undergo a substantial change after operation of the disturber. The effects can be seen in the form of deep trenches and grooves, formed by the action of the sleds and the pumping of the sediment along its path, as well as sediment piles on either side of the track. Biological traces such as fecal coils, casts, tubes, burrows, and trails get obliterated in the areas of disturbance and resedimentation. The smooth, uniform nature of the seafloor observed in predisturbance phase shows microtopographic changes in and around the disturbed area as a result of sediment excavation and resettlement. Vertical mixing as well as lateral transport of sediment alter the geological, biological, physical, and chemical conditions on the seafloor, which need to be monitored over time to assess the process and the time taken for restoration of environmental conditions. 相似文献
19.
Vance P. Vicente 《Marine Ecology》1989,10(2):179-191
Abstract. Long-term changes in the distributional patterns of commercial sponges ( Spongia spp. and Hippospongia spp.) within the West Indian Region indicates that: 1) commercial sponges had a widespread distribution throughout the whole West Indian Region and were ubiquitous in very shallow water until about the first half of the present century; 2) they were fished commercially not only in the traditional northern Caribbean sites (Florida, Gulf of Mexico, Bahamas) but also in the Greater ( e. g. , Hispaniola, Jamaica) and Lesser Antilles; and 3) they became extinct throughout most of the Lesser Antilles ( e. g. , Puerto Rico, Vieques, St. Thomas) sometime during the first half of this century. Mortalities of spongiids within the Antilles were found to differ from other marine mortalities in that: 1) species disappeared from a large region; 2) species vanished from different habitats and depths; and 3) natural populations never recovered. Species richness patterns suggest that commercial sponge genera ( Spongia and Hippospongia ) evolved under slightly cooler elimatic conditions than those found at present, and that these extinctions occurred as a direct or indirect effect of positive thermal anomalies in sea surface and atmospheric temperatures between 1900–1950. The concept that species diversity is stable on a regional scale is questioned. 相似文献
20.
The behaviour of an axially pre-loaded cylindrical member of an offshore structure, hit by a supply ship, has been investigated. The effects of axial pre-loading on the dynamic properties of members, the extent of damage and propagation of dynamic instability in the tubular members have also been investigated. Numerical models have been validated using available experimental data from the literature although these are mostly static with no pre-loading. Axial pre-loading was found to change the dynamic characteristics of some cylindrical members quite dramatically while it had no significant effect on others. The study examined whether there was any change in the behaviour between local and global modes when the loading was dynamic rather than static. The effect of damping on the dynamic instability of axially pre-loaded tubes under lateral dynamic loads was also studied. It was observed that for some geometries the quasi-static response can be used to define the boundary between bounded and unbounded dynamic responses. The main contribution of this study, compared with previous investigations reported in the literature, is that both pre-loading and dynamic effects have been included. 相似文献