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131.
Microalgae and cyanobacteria represent a diverse renewable resource with significant potential for the industrial production of goods and services with high added value. However, scientific, technical/technological, legislative and market gaps and barriers still limit the growth of these markets in Europe and the number of exploited species. We conducted an in-depth survey of European microalgae researchers, experts and stakeholders to identify these limitations and to discuss strategies, recommendations and guidelines to overcome these barriers. Here, we present the findings of this study which detail the main promising markets for microalgae and cyanobacteria in the coming decades, an updated SWOT analysis of the sector, the current opportunities, limitations, risks and threats for microalgae research and market sectors in Europe, a traffic light analysis for a quick assessment of market opportunities for each microalgae sector and detailed recommendations/guidelines for overcoming the scientific, technical/technological, legislative and market gaps and barriers.  相似文献   
132.
蓝藻是生物土壤结皮的重要组成部分,具有许多重要的生态功能。迄今为止,黄土高原地区生物结皮中藻类的种类组成及分布鲜有报道。通过野外调查、采样和室内观察、培养、鉴定,对黄土高原水蚀区、水蚀风蚀交错区、风蚀区的生物结皮中蓝藻的多样性及优势种进行了研究。结果表明,黄土高原3个侵蚀类型区生物结皮中蓝藻门植物共发现4科10属54种,其中丝状种类约占87%,占绝对优势;Shannon-Weiner 多样性指数水蚀风蚀交错区最高,水蚀区次之,风蚀区最低,依次为2.22,2.20和2.14。水蚀风蚀交错区和水蚀区蓝藻多样性指数差异不显著,但均与风蚀区差异显著。3个侵蚀类型区的生物结皮中蓝藻的种类组成及优势种均有所差异,但均以颤藻科(Oscillatoriaceae)为优势科。水蚀风蚀交错区蓝藻种类最多(39种),以阿氏鞘丝藻(Lyngbya allorgei)为第一优势种;水蚀区次之(26种),以含钙席藻(Phormidium calciola)为第一优势种;风蚀区最少(20种),以颗粒颤藻(Oscillatoria granulata)为第一优势种。黄土高原不同侵蚀类型区生物结皮中蓝藻的多样性差异可能与土壤质地、土壤pH值、气候环境等有关。  相似文献   
133.
Phylogeny is an evolutionary reconstruction of the past relationships of DNA or protein sequences and it can further be used as a tool to assess population structuring, genetic diversity and biogeographic patterns. In the microbial world, the concept that everything is everywhere is widely accepted. However, it is much debated whether microbes are easily dispersed globally or whether they, like many macro-organisms, have historical biogeographies. Biogeography can be defined as the science that documents the spatial and temporal distribution of a given taxa in the environment at local, regional and continental scales. Speciation, extinction and dispersal are proposed to explain the generation of biogeographic patterns. Cyanobacteria are a diverse group of microorganisms that inhabit a wide range of ecological niches and are well known for their toxic secondary metabolite production. Knowledge of the evolution and dispersal of these microorganisms is still limited, and further research to understand such topics is imperative. Here, we provide a compilation of the most relevant information regarding these issues to better understand the present state of the art as a platform for future studies, and we highlight examples of both phylogenetic and biogeographic studies in non-symbiotic cyanobacteria and cyanotoxins.  相似文献   
134.
Cyanobactins are a recently recognized group of ribosomal cyclic peptides produced by cyanobacteria, which have been studied because of their interesting biological activities. Here, we have used a PCR-based approach to detect the N-terminal protease (A) gene from cyanobactin synthetase gene clusters, in a set of diverse cyanobacteria from our culture collection (Laboratory of Ecotoxicology, Genomics and Evolution (LEGE) CC). Homologues of this gene were found in Microcystis and Rivularia strains, and for the first time in Cuspidothrix, Phormidium and Sphaerospermopsis strains. Phylogenetic relationships inferred from available A-gene sequences, including those obtained in this work, revealed two new groups of phylotypes, harboring Phormidium, Sphaerospermopsis and Rivularia LEGE isolates. Thus, this study shows that, using underexplored cyanobacterial strains, it is still possible to expand the known genetic diversity of genes involved in cyanobactin biosynthesis.  相似文献   
135.
Microcystins are acute hepatotoxins of increasing global concern in drinking and recreational waters and are a major health risk to humans and animals. Produced by cyanobacteria, microcystins inhibit serine/threonine protein phosphatase 1 (PP1). A cost-effective PP1 assay using p-nitrophenyl phosphate was developed to quickly assess water and rumen content samples. Significant inhibition was determined via a linear model, which compared increasing volumes of sample to the log-transformed ratio of the exposed rate over the control rate of PP1 activity. To test the usefulness of this model in diagnostic case investigations, samples from two veterinary cases were tested. In August 2013 fifteen cattle died around two ponds in Kentucky. While one pond and three tested rumen contents had significant PP1 inhibition and detectable levels of microcystin-LR, the other pond did not. In August 2013, a dog became fatally ill after swimming in Clear Lake, California. Lake water samples collected one and four weeks after the dog presented with clinical signs inhibited PP1 activity. Subsequent analysis using liquid chromatography-mass spectrometry (LC-MS/MS) detected microcystin congeners -LR, -LA, -RR and -LF but not -YR. These diagnostic investigations illustrate the advantages of using functional assays in combination with LC-MS/MS.  相似文献   
136.
137.
双壳贝类是淡水生态系统常见的滤食性动物,以浮游植物和有机物悬浮颗粒为食,其作用可能降低蓝藻浓度,从而促进沉水植物生长。通过构建4组(草+蓝藻、草+蓝藻+低生物量蚌、草+蓝藻+高生物量蚌、草)室外微型生态系统,研究了湖泊下风区常见蓝藻堆积浓度下,三角帆蚌(Hyriopsis cumingii)的滤食作用对蓝藻水华和沉水植物苦草(Vallisneria natans)生长的影响。结果表明:(1)蓝藻对苦草的生长具有显著抑制作用,草藻组和草组的相对生长率分别为-7.65mg/g·d和7.19mg/g·d;(2)  相似文献   
138.
不同镁/磷盐添加剂对蓝藻堆肥的氮素损失控制效果   总被引:1,自引:1,他引:0  
为探究蓝藻好氧堆肥过程中较佳的氮素损失控制措施,以蓝藻为主要原料,菌渣、稻壳为调理剂,4种不同组合的镁盐和磷盐[Mg(OH)2+H3PO4(MP)、Mg(OH)2+KH2PO4(MKP)、MgSO4+H3PO4(MSP)、MgSO4+KH2PO4(MSKP)]为添加剂进行好氧堆肥试验,对不同处理下的氮素损失控制效果进行研究。结果表明:MP、MKP、MSP和MSKP处理组的NH3排放量相较于空白对照组分别降低了48.98%、45.95%、76.91%和38.65%; TN含量相较于初始值分别增加了66.31%、54.42%、30.15%和46.50%;氮素固定率分别为44.26%、41.36%、71.09%和33.54%。X射线衍射(XRD)分析结果证实不同处理组堆肥产品中均有鸟粪石(MgNH4PO4·6H2O)的存在。堆肥42 d后,除MSP处理组外,各组均已达到腐熟状态,且符合NY 525—2012标准。综合来看,MKP处理的氮素固定率略低于MP处理,但具有更高的微囊藻毒素降解率与总养分含量,是蓝藻堆肥工程化应用中理想的保氮方式。  相似文献   
139.
近年来以微囊藻为优势种的太湖蓝藻水华持续暴发,已经成为严重的环境问题之一。本文通过现场采样及室内分析,研究了2009年太湖南泉水域蓝藻发生过程中藻类群落组成的变化,并同步研究了蓝藻体内及其水环境中常量元素Ca、Na、Mg、K和Al元素浓度的周年变化,分析了三者之间可能的相关性。研究显示,太湖蓝藻发生时间为6—10月,期间水温保持在20℃以上,pH值在水华发生后期可升高至9.8;水体中元素浓度依次为Na〉Ca〉Mg〉K〉Al,而水华蓝藻中元素浓度依次为Ca〉K〉Mg〉Na〉Al;藻体对水体环境中元素的富集系数大小依次为Al〉K〉Mg〉Ca〉Na。研究结果既为选择最佳物理除藻时期来有效降低湖泊中常量元素的负荷量,从而进行水华控制提供了支撑,也为今后将富含元素的水华蓝藻作为"生物矿源"加以利用提供了理论依据。  相似文献   
140.
Peloids have been used for therapeutic purposes since time immemorial, mainly in the treatment of locomotor system pathologies and dermatology. Their effects are attributed to their components, i.e., to the properties and action of mineral waters, clays, and their biological fraction, which may be made up of microalgae, cyanobacteria, and other organisms present in water and clays. There are many studies on the therapeutic use of peloids made with microalgae/cyanobacteria, but very little research has been done on dermocosmetic applications. Such research demonstrates their potential as soothing, regenerating, antioxidant, anti-inflammatory, and antimicrobial agents. In this work, a method for the manufacture of a dermocosmetic peloid is presented based on the experience of the authors and existing publications, with indications for its characterization and study of its efficacy.  相似文献   
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