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1.
从厚藤共生真菌(Fusarium oxysporum Y24-2)发酵液中提取得到胞外多糖,以Q-Sepharose Fast Flow阴离子交换柱和Superdex S-75凝胶色谱柱对其进行分离纯化,得到纯度高的多糖组分F1S。采用HPGPC和HPLC对F1S的分子量及单糖组成进行分析,结果表明F1S主要由Man、Glc和Gal组成,其摩尔比为1.0∶1.9∶2.1,分子量为37.3kD。F1S的GC-MS和1D,2D-NMR分析表明,该多糖是以→6)-β-Galf(1→为主链,以→2)-α-Glcp(1→,α-Glcp(1→和β-Manp(1→为支链的杂多糖,支链取代于→6)-β-Galf(1→的O-2位。该厚藤共生真菌的胞外多糖为富含呋喃型半乳糖的结构新颖的具有多分支结构的中性杂聚多糖。 相似文献
2.
本文以刺松藻(Codium fragile)为原料,依次经冷水、热水提取,得到2种粗多糖CFC和CFH,经Q-SepharoseFF强阴离子交换色谱分离,分别从CFC和CFH中得到组分CFCP1～P6和CFHP1～P5,并对其理化性质进行了分析。分别运用高效凝胶渗透色谱法(HPGPC)、高效离子色谱法(HPIC)、傅里叶变换红外光谱法(FTIR)对其分子量、单糖组成和结构特征进行了分析。结果表明,刺松藻中多种结构复杂的多糖,CFCP1和CFCP6属于硫酸阿拉伯半乳聚糖,CFCP4和CFHP5属于丙酮酸化的硫酸半乳聚糖,CFHP1和CFHP2分别属于葡聚糖和甘露聚糖。多糖CFCP2、CFHP2和CF-HP3中除了含有半乳糖、阿拉伯糖、葡萄糖和甘露糖外,还含有木糖、鼠李糖和岩藻糖。这些结构特殊的多糖为海洋药物研究与开发提供了良好基础。 相似文献
3.
以海萝藻(Gloiopeltis furcata)为原料,依次经冷水、热水和热碱溶液提取,从中获得了3种多糖(GFW,GFH和GFA),其得率分别为57.9%,2.5%和2.6%。运用气相色谱法(GC)、高效凝胶渗透色谱法(HPGPC)、红外光谱(IR)及核磁共振碳谱(13C-NMR)等方法对其单糖组成、分子量以及结构进行了分析。结果表明,GFW和GFH都只含有D-半乳糖(Gal)和3,6-内醚-L-半乳糖(AnG),而GFA除了含有Gal和AnG外,还有木糖;3种多糖的分子量分别为22.6 kD,26.5 kD和49.8 kD;硫酸基含量分别为31.2%,25.1%,22.7%。IR和13C-NMR数据均表明其硫酸基在半乳糖残基C6位。结论:海萝藻中多糖均为硫酸多糖,其中2种为硫琼胶,另一种为含有木糖的硫酸半乳聚糖。 相似文献
4.
本文以厚叶切氏海带(Kjellmaniella crassi folia)为原料,经提取分离获得4种多糖(KW1,KW2,KA1和KA2).运用电泳、高效液相色谱(HPLC)、高效凝胶渗透色谱(HPGPC)及核磁共振氢谱(1H-NMR)法分别对其单糖组成、相对分子量(Mr)以及结构进行分析.结果表明,KW1与KA1是Mr为520 kD和430 kD且M/G(6.14和1.90)显著不同的褐藻胶;KW2是以岩藻糖(82％)为主的岩藻糖硫酸酯;KA2是以半乳糖(34％)、岩藻糖(27％)和甘露糖(21％)为主的杂聚硫酸多糖.KW2和KA2的Mr和硫酸基含量分别为536 kD和427 kD及30％和21％.经1 H-NMR分析表明,KW2的硫酸酯基主要存在于岩藻糖残基的C2和C4位. 相似文献
5.
主要采用傅里叶红外光谱(fourier transform infrared spectroscopy, FTIR)、气相色谱(gas chromatography, GC)和凝胶渗透色谱(gel permeation chromatography, GPC)方法对5种海藻粗多糖的单糖组成、官能团、分子量进行了初步分析。结果显示5种海藻粗多糖均含有木糖和岩藻糖, 其中南方团扇藻多糖含有较为丰富的山梨糖, 属于大分子量均一性多糖, 而孔石莼多糖分子量分布较宽, 均一性较差。红外光谱分析结果表明, 5种粗多糖均为酸性多糖, 棒叶蕨藻、琼枝麒麟菜和匍枝马尾藻多糖具有明显的硫酸基团吸收峰, 琼枝麒麟菜多糖存在呋喃糖和吡喃糖, 并且吡喃糖苷键可能存在β和α两种类型。明胶氯化钡实验结果指出南方团扇藻多糖的硫酸基团含量为38.43%(±2.38%), 明显高于其他几种海藻多糖, 而棒叶蕨藻多糖的硫酸基团含量最低, 仅为8.92%(±1.04%)。 相似文献
6.
毛细管气相色谱法测定海带提取多糖中的L-褐藻糖含量 总被引：1，自引：0，他引：1
建立快速而准确灵敏的方法测定海带(Laminaria japonica)提取多糖——褐藻多糖硫酸酯中的L，褐藻糖含量。海带多糖经酸解后，转化成糖腈乙酸酯衍生物。采用SGEAC225毛细管柱进行分离，实验中以肌醇为内标物。从青岛产海带提取的褐藻多糖硫酸酯中仅含有L，褐藻糖和I)-半乳糖2种单糖，样品10-1，10-2，10-3，1阻4中的L褐藻糖的平均含量分别为32．9072％，32．3147％，31．2924％，32．3571％，回收率为97．1％～99．9％，变异系数为0．23％～0．60％。采用气相色谱法测定海带多糖中的L褐藻糖含量准确、可靠。 相似文献
7.
以龙须菜粗多糖为原料,利用离子交换层析分离纯化,紫外光谱、醋酸纤维薄膜电泳和凝胶过滤层析法鉴定多糖的纯度及其分子量,同时进一步采用气相色谱分析龙须菜多糖的单糖组成.结果表明,利用蒸馏水、0.3mol/L NaCl和1.2mol/L NaCl溶液分步洗脱,DEAE-Sephadex A-25离子交换层析纯化得到龙须菜多糖的三个组分G1、G2和G3,得率分别为3.61%、69.26%、18.70%:G1、G2和G3均显示为单一电泳谱带和单一洗脱峰,无蛋白、核酸杂质,分子量依次为21993、48460、61031U;G2和G3的单糖组成主要为半乳糖、3.6-内醚半乳糖及少量葡萄糖;G2糖链通过1→2键与1→6键方式连接,存在非还原末端基及连三羟基,G3糖链则通过1→3键与1→2键方式连接. 相似文献
8.
螺旋藻多糖和糖蛋白的提纯及其理化特性研究 总被引：6，自引：0，他引：6
采用改进的人螺旋藻中提取多糖和糖蛋白。经恒温加热去蛋白后，用EDAE－52柱层析后得到一种多糖和两种糖蛋白，经Sephadex G-100和凝胶电泳证实所得的多糖和糖蛋白为组的一组分。采用凝胶过滤法测定的多糖近似分子量为19500。由SDS－PAGE测定分子量糖蛋白GS－1的分子量为14900，GS－2的分子量为18400。红外光谱呈现出典型的多糖吸收峰，含有α－型糖苷键。β消去反应初步证明所提取的两种糖蛋白可能是O－连续的糖蛋白。 相似文献
9.
三种绿藻多糖的提取及理化性质和活性比较 总被引：3，自引：0，他引：3
采用80℃水浴8h、乙醇沉淀、Sevage法去除蛋白质的方法提取湛江裂片石莼、肠浒苔和总状蕨藻多糖，并用Molish反应、Fehling反应鉴定多糖的化学性质，用苯酚-硫酸法测定多糖的总糖含量，用Dodgson法测定多糖的硫酸基含量，用Folin-酚法测定多糖的蛋白质含量．结果表明：3种绿藻的多糖提取率和多糖总糖含量以裂片石莼最高，分别为3．0％和72．6％，总状蕨藻最低分别为1．65％和38．6％；3种绿藻的硫酸基含量相差不大．总状蕨藻的蛋白质含量最高，为14．5％．3种多糖溶液作用于体外白血病细胞结果以总状蕨藻的抑制效果最明显，浓度为12mg／dm^3的总状蕨藻多糖溶液作用72h的抑瘤率达66％． 相似文献
10.
利用高效凝胶渗透色谱法(HPGPC)和明胶比浊法研究了海洋硫酸多糖916在溶菌酶和胰蛋白酶作用下的稳定性，分别考察了酶作用下916的重均分子量、分子量分布系数和游离硫酸根含量的变化。结果表明：在所选定的实验条件下，916的重均分子量、分子量分布系数和游离硫酸根含量均未发生显著变化，表明在所选择的实验条件下916对溶菌酶和胰蛋白酶是稳定的。 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
17.
Chandralata Raghukumar G. Sheelu P. A. Loka Bharathi Shanta Nair C. Mohandass 《Marine Georesources & Geotechnology》2001,19(1):1-16
In order to assess the impact of deep-sea mining on the in situ benthic life, we measured the microbial standing stock and concentration of organic nutrients in the deep-sea sediments of the Central Indian Ocean Basin in the Indian pioneer area. Sediments were collected using box core and grab samples during September 1996. The total bacterial numbers ranged from 10 10 -10 11 cells per g -1 dry weight sediment. There was a marginal decrease in the number of bacteria from surface to 30 cm depth, though the subsurface section registered a higher number than did the surface. The highest numbers were encountered at depths of 4-8 cm. The retrievable number of bacteria were two orders less in comparison with the direct total counts of bacteria. An almost homogeneous distribution of bacteria, total organic carbon, living biomass, and lipids throughout the depth of cores indicates active microbial and benthic processes in the deep sea sediments. On the other hand, a uniform distribution of total counts of bacteria, carbohydrates, and total organic carbon in all the cores indicates their stable nature and suggests that they can serve as useful parameters for long-term monitoring of the area after the benthic disturbance. Further studies on temporal variability in this region would not only verify the observed norms of distribution of these variables but would also help to understand restabilization processes after the simulated benthic disturbance. 相似文献
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Coastal inundation associated with extreme sea levels is the main factor which leads to the loss of life and property whenever a severe tropical cyclonic storm hits the Indian coasts. The Andhra and Orissa coasts are most vulnerable for coastal inundation due to extreme rise in sea levels associated with tropical cyclones. Loss of life may be minimized if extreme sea levels and associated coastal flooding is predicted well in advance. Keeping this in view, location specific coastal inundation models are developed and applied for the Andhra and Orissa coasts of India. Several numerical experiments are carried out using the data of past severe cyclones that struck these regions. The simulated inland inundation distances are found to be in general agreement with the reported flooding. 相似文献
20.
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