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1.
褐藻多糖的药理作用与制备   总被引:3,自引:0,他引:3  
阐述了褐藻糖胶的化学组成和结构。从褐藻中提取分离得到的褐藻糖胶具有显著的抗癌、抗凝、降脂、免疫调节和抗衰老作用,既可作为保健食品,也可作为治疗药物。目前,我国制备褐藻糖胶,主要采用60%乙醇沉淀法和CPC沉淀法从海带水碱凝沉物中提取,或用稀酸直接从海带中提取,并用乙醇分级法和色谱法对褐藻糖胶进行纯化。  相似文献   

2.
包埋脱水法冷冻保存裙带菜配子体克隆的研究   总被引:6,自引:0,他引:6  
将裙带菜配子体克隆包埋在含3%褐藻酸钙的胶球中,研究了预培养中的蔗糖浓度和培养时间,脱水过程中的脱水速率和胶球含水量以及化冻速度对配子体克隆的存活率和发育能力的影响,结果表明含裙带菜配子体克隆的胶球在0.3 mol/dm3的蔗糖培养基中培养9 h可以获得较高的存活率;胶球最适平均脱水速率为含水量的5%每小时,最适含水量为25%;较快的化冻速度可以显著提高配子体克隆的存活率,在优化条件下存活率可高达66%;经过冷冻保存的裙带菜配子体克隆在适合发育的条件下能够正常形成孢子体.  相似文献   

3.
在海洋腹足类动物的消化器官内,发现褐藻糖胶酶(fucoidanase)的甚少。Galli等在一种食植性马蹄螺(Tegula funebralis)的中肠提取液,以及Alexander等在红树林潮间带一种食碎腹足类(Telescopium telescopium)的晶杆中都测得褐藻糖胶酶的活性。Alexander等还报道了该酶的最适pH为6,饱和底物浓度为6mg/ml°有关该酶的其他反应动力学特性未见报道。 我们在研究三种海螺,食植性的朝鲜花冠小月螺(Lunella coronata coreensis)、杂  相似文献   

4.
刘洪艳 《海洋通报》2007,26(6):37-41
以褐藻裙带菜(Undaria pinnatifida)和绿藻石莼(Ulva pertusa)为实验材料,利用SDS,Dig,Triton X-100三种去污剂,分别与叶绿素按不同比例增溶类囊体膜,采用蔗糖密度梯度超速离心的方法分离色素蛋白复合物,蔗糖密度梯度为60%,50%,40%,30%,20%,15%和10%。实验结果表明:当SDS与叶绿素质量比为20∶1时,能够从裙带菜类囊体膜中分离得到5条含蛋白质复合物带。对于石莼类囊体膜的增溶,当SDS与叶绿素的质量比为10∶1,Triton与叶绿素质量为20∶1时,同样能够分离得到5条含蛋白质复合物带。褐藻和绿藻色素蛋白复合物对去污剂的敏感程度有很大差别。  相似文献   

5.
以褐藻裙带菜(Undaria pinnatifida)为实验材料,建立一条能够分离出有光活性PSⅡ复合物的技术路线。采用蔗糖密度梯度超速离心的方法,以去污剂SDS为增溶剂(SDS∶Chl=20∶1,4℃增溶20 min),蔗糖质量分数梯度为10%,15%,20%,30%,40%,50%和60%,从裙带菜中成功地分离出5条含色素的蛋白质复合物带。通过对裙带菜各色素蛋白复合物的光谱分析并进行了DCIP的光还原测定和化学法的氧化还原差示光谱测定,确定了20%和30%层带的复合物为PSⅡ复合物,具有DCIP的光还原活性。利用离子交换层析的方法并通过光谱鉴定分析得到了比较纯化的PSⅡ中心复合物。  相似文献   

6.
以大型经济褐藻裙带菜配子体为实验材料,采用活性检测法对雌诱激素在有性生殖过程中的作用进行了研究。结果表明,刚刚排出的雌配子分泌了一种或几种易挥发的激素类物质,这些激素类物质能够促进精子释放并吸引精子向其游动,完成受精作用。另外,通过显微计数释放精子数的方法对影响裙带菜雌诱激素分泌的培养时间和培养的光照强度、环境温度、光...  相似文献   

7.
裙带菜的孤雌生殖及其后代的遗传特点   总被引:3,自引:1,他引:3  
若干海藻工作者已在海带、厚叶翅藻等褐藻中观察到孤雌生殖的现象[1][3][4]。我们于1973年开始了海带单倍体遗传育种的实验后,从1974年起我们就裙带菜(Undaria pinnatifida Sur.)进行了相似的试验。这里着重就裙带菜的孤雌生殖及其后代所表现的细胞遗传学特点,进行一些观察。大部分材料是1977年的实验结果。关于裙带菜配子体的无性生殖系将另作总结。  相似文献   

8.
褐藻多糖硫酸酯是一种含有硫酸基的水溶性杂聚糖,其化学组成对抗氧化活性有较大的影响。本文对三种褐藻来源的褐藻多糖硫酸酯及其降解产物化学组成和抗氧化活性进行了研究,阐明了不同来源褐藻多糖硫酸酯体外抗氧化活性的构效关系。实验结果表明:1)分子量对抗氧化活性有较大影响,但是对不同褐藻来源的褐藻多糖硫酸酯的影响趋势并不一致。2)岩藻糖、硫酸基和糖醛酸含量对清除超氧阴离子自由基的影响与分子量有一定的关系。对于低分子量样品,岩藻糖和硫酸基含量与抗氧化活性成正相关。3)岩藻糖和硫酸根的比值对羟基自由基的清除能力有一定影响,比值越大,羟基自由基的清除能力越强。分子量、岩藻糖、硫酸基和糖醛酸的含量对褐藻多糖硫酸酯的抗氧化活性的影响依次减小。本研究为褐藻多糖硫酸酯在抗氧化剂保健品和功能食品中的应用提供了基础数据,也为裙带菜、羊栖菜和铜藻的高值化利用提供了理论依据。  相似文献   

9.
裙带菜的化学成分及其生物活性研究进展   总被引:2,自引:0,他引:2       下载免费PDF全文
裙带菜(Undaria pinnatifida(Harv.)Surin-gar)又名海芥菜,是翅藻科(Alariaceae)、裙带菜属(Undaria)的一种大型经济褐藻,在我国主要分布在辽宁、山东、江苏、浙江等地[1].裙带菜的叶状体不但可食用,还可作为中药使用,其药用历史最早见于明代姚可成的<食疗本草>:"裙带菜主女人赤白带下,男子精泄梦遗"[2].近代认为裙带菜与昆布化学成分相似,将其作为中药昆布入药,具有消痰软坚,利水退肿的功效[1,2].  相似文献   

10.
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   

11.
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.
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   

14.
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.
18.
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   

19.
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   

20.
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   

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