共查询到20条相似文献，搜索用时 46 毫秒
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有毒赤潮藻及其毒素的危害与检测 总被引：6，自引：0，他引：6
海洋中可引发赤潮的藻类约有300种,其中有毒赤潮藻为80种左右。现已知道的赤潮藻主要毒素有麻痹性贝毒、腹泻性贝毒、记忆缺失性贝毒、神经性贝毒、西加鱼度和溶血性毒素,前5种毒素的结构已经基本得到证实。有毒赤潮藻的毒素可以在海洋生物体内积累,人类误食含有藻毒素的食品时可能中毒,严重者还可能死亡。海洋有毒赤潮藻及其毒素的检测已经成为当今全球赤潮研究和监测的重要内容之一,可以通过形态学分类方法、分子生物学技术(遗传探针)和免疫学检测技术对有毒赤潮藻进行检测;可以通过生物学、物理化学检测方法和神经受体结合、免疫学检测技术对赤潮藻毒素进行检测。 相似文献
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Eduard A. Titlyanov Tamara V. Titlyanova Bangmei Xia Inka Bartsch 《Ocean Science Journal》2016,51(3):485-506
Retrospective analysis of diversity and species composition of marine macroalgae of Hainan Island in the period 1933–1992 is presented in this paper. There are two extensive sample collection periods of benthic macroalgae: the early collection (EC) covers a period between the early 1930s and the 1980s before considerable urbanization and reef degradation took place and a late collection (LC) was performed in 1990/1992 during a phase of rapid urbanization. Analysis of data also including an earlier published inventory of green algae covering the same collection sites (Titlyanov et al. 2011a) revealed that the marine flora of the island comprises 426 taxa in total, with 59% red algae, 18% brown algae and 23% green algae. In total 59 species of red algae, 11 species of brown algae and 37 species of green algae sampled during the LC are new records for Hainan Island. Considerable floristic changes between EC and LC became evident. In the LC there were significantly more filamentous, tubular or fine blade-like, and often epiphytic, green and red algae with a high surface-to-volume ratio. Additionally a reduction of green, brown and red algal species with larger fleshy or foliose thalli and a low surface-to-volume ratio was observed. It is assumed that the changes reflect the degradation of the coral reef ecosystem around Hainan, which was damaged by human activities especially in the 1950s–1970s. 相似文献
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南麂列岛潮间带海藻资源与生态 总被引：8，自引：0，他引：8
本文报道了１９９２年５月～１９９３年３月南麂列岛潮间带海藻四季调查结果。共鉴定大型海藻１２１种，隶属于６６个属，其中红藻类８２种，褐藻类２５种，绿藻类１２种，蓝藻类２种。海藻组成以暖温性与亚热带性种类占优势。海藻区系特征与台湾暖流和浙江沿岸流对本海域影响密切相关。该区域海藻的种类组成、数量分布和垂直分布，都有明显的季节变化。本文还分析了海藻分布与生态环境因子的关系，认为潮汐主导海藻的垂直分布，温度决定海藻分布的季节变化。 相似文献
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南极红藻具有重要的生态学功能和开发利用价值。南极极端环境赋予了其独特的生理耐受机制，也是发现新基因和代谢途径的理想材料。我们测序分析了南极产胶红藻Iridaea cordata (Turner) Bory和Curdiea racovitzae Hariot的转录组序列，并与其常温近缘种进行了比较，同时挖掘了其与光限制和强紫外线辐射等光环境适应相关的基因。I. cordata和C. racovitzae的转录组序列分别拼接成了14055条和12006条非冗余基因，平均长度分别为1473 bp和1448 bp。在I. cordata转录组中发现多条与绿藻基因同源的捕光复合物LHC基因Lhca2、Lhca6和Lhcb，并且在两种南极红藻中都各发现了1条编码结合岩藻黄质和Chl a/c蛋白的Lhcf基因，目前尚未在其他红藻中发现这类基因。光裂解酶修复紫外线诱导DNA损伤，在I. cordata的转录组序列中发现了6?4光裂解酶，光裂解酶CPD I和CPD II基因，而C. racovitzae转录组序列中仅找到了光裂解酶CPD II基因。尽管南极红藻中这些特有基因的功能有待进一步的验证，但是本文为后续研究红藻的南极极端光环境适应机制提供了方向。 相似文献
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许多研究已经表明，类胡萝卜素是分布最广泛、最重要的一类光辅助合成色素。类胡萝卜素具有多种生物学功能：作为化学保护剂可抵抗由植物自身叶绿素的光敏氧化作用引起的有害作用，给人体补充β-胡萝卜素可有效降低心血管疾病和癌症的发生概率，高摄入富含类胡萝卜素的饮食和降低白内障发生的危险之间有重要联系(Bendich，1993)。海藻中含有丰富的类胡萝卜素，从结构类型说，通常可以分为三类：胡萝卜素、叶黄素和类胡萝卜素酸。海藻中还含有多种特有的类胡萝卜素，如褐藻黄素、甲藻黄素、硅藻黄素等。直到目前为止，海藻中类胡萝卜素的组成与生理学功能尚没有明确的结论，因而对我国丰富的海藻资源中的类胡萝卜素进行较为系统和全面的化学及生物活性研究已成为摆在我们面前的一个重要课题。本研究选取我国青岛海滨三类大型经济海藻——红、绿、褐藻中资源量丰富的代表性种类作为实验材料，较系统地测定了其中类胡萝卜素的含量，并运用经典的柱层析法对各类胡萝卜素组分进行了分离，通过薄层分析和可见光谱扫描对各分离组分进行了定性、定量分析。 相似文献
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核酸分析技术在红藻分子系统学研究中的应用 总被引：1，自引：1，他引：1
在红藻的分子系统学研究中,核酸分子数据的获得和应用日益显得重要,因为核酸序列是进化的重要单元,通常以点突变来体现种间/种内的差异,因此能反映物种进化过程的频率.目前,在红藻分子系统学研究中,核酸标记技术有：限制性片段长度多态性（RFLP）、随即扩增多态性DNA（RAPD）、扩增片段长度多态性（AFLP） 和简单重复序列间扩增（ISSR）;相关核酸分析技术涉及到的序列有：内转录间隔区（ITS）、18S和26S rRNA,核糖体大、小亚基（LSU和SSU）,Rubisco基因及大、小亚基.其在红藻品种鉴定、种群遗传、分类和系统进化的研究中起重要的作用. 相似文献
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The seasonal occurrence of 94 benthic algal species, including Cyanophyta, was observed on a monthly basis over one year in the Patos Lagoon estuary (32°S, 52°W), Brazil, and showed three patterns of algal periodicity. An aseasonal group of 46 species was present throughout the year and two groups of 24 species each occurred either during summer and fall or winter and spring. The seasonal growth of 55 green, brown and red algae was correlated with monthly variations of salinity, water temperature, daylength and light radiation energy, which were measured daily in the estuary. Summer/fall peak growth was observed in 15 algae most of which correlated significantly with high salinities alone or in combination with other factors during this period. Growth peak of 11 species in winter/spring was principally a function of low water temperatures alone or together with a reduced light regime.Both periodicity of benthic algae and their seasonal growth, as a more sensitive measure of their floristic affinity, demonstrated the presence of cool temperate and tropical elements in this flora typical for warm temperate biogeographic regions. Correlations between seasonal variation of algal growth and selected environmental parameters aided in the evaluation of causal factors for algal seasonality. 相似文献
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Phylogenomic analysis of transcriptomic sequences of mitochondria and chloroplasts for marine red algae (Rhodophyta) in China 总被引：1，自引：1，他引：0
JIA Shangang WANG Xumin QIAN Hao LI Tianyong SUN Jing WANG Liang YU Jun LI Xingang YIN Jinlong LIU Tao WU Shuangxiu 《海洋学报(英文版)》2014,33(2):86-93
The chloroplast and mitochondrion of red algae （Phylum Rhodophyta） may have originated from different endosymbiosis. In this study, we carried out phylogenomic analysis to distinguish their evolutionary lin-eages by using red algal RNA-seq datasets of the 1 000 Plants （1KP） Project and publicly available complete genomes of mitochondria and chloroplasts of Rhodophyta. We have found that red algae were divided into three clades of orders, Florideophyceae, Bangiophyceae and Cyanidiophyceae. Taxonomy resolution for Class Florideophyceae showed that Order Gigartinales was close to Order Halymeniales, while Order Graci-lariales was in a clade of Order Ceramials. We confirmed Prionitis divaricata （Family Halymeniaceae） was closely related to the clade of Order Gracilariales, rather than to genus Grateloupia of Order Halymeniales as reported before. Furthermore, we found both mitochondrial and chloroplastic genes in Rhodophyta under negative selection （Ka/Ks〈1）, suggesting that red algae, as one primitive group of eukaryotic algae, might share joint evolutionary history with these two organelles for a long time, although we identified some dif-ferences in their phylogenetic trees. Our analysis provided the basic phylogenetic relationships of red algae, and demonstrated their potential ability to study endosymbiotic events. 相似文献
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Technetium (Tc) biokinetics were investigated in marine macroalgae using 92mTc as tracer. Green and red algae accumulated Tc (VII) to a very low degree (CF ? 1–20); however, a much higher affinity for pertechnetate was found in some brown algal species (CF > 103). Comparative tests with different species of brown algae revealed that technetium does not accumulate similarly in all species of this group. Moreover, no significant differences in radionuclide uptake were noted between brown algae exposed to Tc in either the IV or VII oxidation states. Bioaccumulation of technetium appears to be a metabolically controlled process since uptake did not occur in heat-killed individuals and both light and temperature significantly enhanced the accumulation of technetium in brown algae. Dissection of Sargassum vulgare following the uptake phase showed that the rapidly growing air bladder, leaf-like laterals and small branches contained higher Tc concentrations and retained a greater fraction of the radioactivity than the older, cylindrical main axis. Pertechnetate retention in two brown algae was found to be significantly different; their biological half-lives for Tc differed by an order of magnitude (). During depuration, loss took place more rapidly from the younger portions of the seaweed, as evidenced by the highest concentration and greatest fraction of Tc retained in the older, cylindrical main axis. Provided certain precautions are taken, brown algae such as Cystoseira compressa and S. vulgare would serve as good bioindicator organisms for the presence of Tc contamination in marine waters. 相似文献
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High-molecular-weight, nondialyzable polyphloroglucinols from the marine brown algae Ascophyllum nodosum and Fucus vesiculosus (Phaeophyceae, Fucales) chelate the divalent metal ions Sr2+, Mg2+, Ca2+, Be2+, Mn2+, Cd2+, Co2+, Zn2+, Ni2+, Pb2+ and Cu2+ in weakly acidic aqueous solution. Values of the relative selectivity coefficients k have been calculated relative to Mn2+; the ionotropic series with the algal polyphenols are similar to those with catechol and pyrogallol. These studies may serve as a guide for the examination of metal chelation by brown algal polyphenols both in situ and after exudation into seawater. 相似文献
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Distribution and biomass of green algal mats were studied in marine shallow (0–1 m) soft-bottom areas on the Swedish west coast from 1994 to 1996, by combining aerial photography surveys with ground truth sampling. Filamentous green algae, dominated by species of the genera Cladophora and Enteromorpha, were generally present throughout the study area during July and August, and largely absent in late April and early May. These algae occurred at 60 to 90% of the locations investigated during the summer, and were estimated to cover between 30 and 50% of the total area of shallow soft bottoms of the Swedish Skagerrak archipelago. The distributional patterns were similar during the three years of the investigation and appeared unrelated to annual local nutrient inputs from point sources and river discharge. We postulate that the apparent lack of such a relationship is due to an altered state of nutrient dynamics throughout the archipelago. Mechanisms are likely to involve long-term, diffuse elevations in nutrient levels in coastal waters of the Skagerrak and the Kattegat over several decades leading to current eutrophic conditions, exceeding nutrient requirements for abundant filamentous algal growth. Patterns of algal abundance in our study were largely related to physical factors such as exposure to wind, waves and water exchange under conditions where nutrient loads among embayments seemed to be unlimited. Further, our results show that sediments covered by algal mats had higher carbon and nitrogen contents than unvegetated sediments. We hypothesise that sustained high nutrient loads, manifested in extensive biomass of filamentous algae during summer months, are re-mineralised via decay and sedimentation in the benthic realm. Hence, accumulated carbon and nutrients in the sediment could, in turn, constitute the basic pool for future algal mat production overlying soft bottoms in areas where tidal exchange is limited. 相似文献