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91.
微藻的保种技术及其应用 总被引:2,自引:0,他引:2
本文介绍了微藻保种的几种常用方法 ,包括继代保存、固定化保存和超低温保存。结果表明 :继代保存简便易行 ,在生产和科研实践中比较实用 ;而固定化保存可用于较长期保存 ;超低温保存则可用于长期保存。另外 ,还对这几种保种技术的研究及应用现状进行了简单概述 ,以期能对微藻保种工作的开展有所裨益 相似文献
92.
93.
几种海洋微藻的碱性磷酸酶性质初步研究 总被引:4,自引:0,他引:4
对5种海洋微藻产生的碱性磷酸酶的性质进行了初步研究并确定了碱性磷酸酶的测定条件。结果表明,在pH 8.2的环境中,各藻产生的碱性磷酸酶最佳反应温度在40~50℃内,且存在一定差异;40℃下酶促反应恒速时间及米氏常数也有所不同,酶活恒速时间顺序为东海原甲藻(Prorocentrum donghaiense)<强壮前沟藻(Amphidinium carterae)<旋链角毛藻(Chaetoceros curvisetus)<中肋骨条藻(Skeletonema costatum)<塔玛亚历山大藻(Al-exandrium tamarense);米氏常数大小顺序为塔玛亚历山大藻<东海原甲藻<中肋骨条藻<强壮前沟藻<旋链角毛藻。碱性磷酸酶测定条件为:温度40℃,反应时间90 min,底物浓度260μmol/L。 相似文献
94.
温度、光照、pH值对后棘藻生长及脂肪酸含量的影响 总被引:3,自引:0,他引:3
报道了环境因子对富含 EPA (2 0∶ 5ω3)的海洋微藻后棘藻 (Ellipsoidion sp.) 70 - 0 1的生长速度、总脂及脂肪酸含量的影响。结果表明 ,后棘藻具有较快的生长速度和较高的脂肪酸含量 ,总脂含量为 31~ 36 % ,主要脂肪酸为 14∶ 0、16∶ 0、16∶ 1、18∶ 1ω9、18∶ 1ω7、18∶ 2 ω6、2 0∶ 4 ω6、2 0∶ 5ω3。生长的温度范围为 15~ 30℃ ,2 5℃时生长速度最快。温度对总脂含量影响很小 ,但对EPA和 PUFA含量影响较大。在 2 5℃时有最大的 EPA和 PUFA含量。适宜光强为 10 8.75μmolm-2 s-1~ 2 4 4 .15μmolm-2 s-1,在 145.54μmolm-2 s-1时 EPA产率较大。在起始 p H6 .5~ 9范围内 ,p H8.5时有最大的生长速率和总脂含量 ,而 EPA和 PUFA在起始 p H7.5时最大 ,分别占脂肪酸的 18.77%和 2 3.38%。实验条件下后棘藻 EPA产率最大的条件为温度 2 5℃ ,光强 145.54μmolm-2 s-1,p H为 7.5~ 8.5。 相似文献
95.
Sediment samples were collected at stations along cross-shelf transects in Onslow Bay, North Carolina, during two cruises in 1984 and 1985. Station depths ranged from 11 to 285 m. Sediment chlorophyll a concentrations ranged from 0·06 to 1·87 μg g−1 sediment (mean, 0·55), or 2·6–62·0 mg m2. Areal sediment chlorophyll a exceeded water column chlorophyll a a at 16 of 17 stations, especially at inshore and mid-shelf stations. Sediment ATP concentrations ranged from 0 to 0·67 μg g−1 sediment (mean, 0·28). Values for both biomass indicators were lowest in the depth range including the shelf break (50–99 m). Organic carbon contents of the sediments were uniformly low across the shelf, averaging 0·159% by weight. Photography of the sediments revealed extensive patches of microalgae on the sediment surface.Our data suggest that viable benthic microalgae occur across the North Carolina continental shelf. The distribution of benthic macroflora on the North Carolina shelf indicates that sufficient light and nutrients are available to support primary production out to the shelf break. Frequent storm-induced perturbations do not favour settling of phytoplankton, an alternative explanation for the presence of microalgal pigments in the sediments. Therefore, we propose that a distinct, productive benthic microflora exists across the North Carolina continental shelf. 相似文献
96.
The role of floating mucilage in the invasive spread of the benthic microalga Chrysophaeum taylorii 下载免费PDF全文
Sarah Caronni Maria Anna Delaria Kirsten Heimann Giovanni Macri Augusto Navone Pieraugusto Panzalis Giulia Ceccherelli 《Marine Ecology》2016,37(4):867-876
Chrysophaeum taylorii Lewis & Bryan (Pelagophyceae) is a mucilage‐producing benthic microalga that has recently begun to spread in the Mediterranean Sea, where a range expansion is occurring. This paper presents the results of three field experiments that aimed to increase the knowledge on mucilage provision mechanisms for this benthic microalga and to evaluate the importance of mucilage in its range expansion. By means of two correlative field experiments (several years of data were considered to encompass the variability of mucilage cover) we found that, on the sea bottom, mucilage cover does not depend on epilithic cell density and that both its cover and settling are affected by water flow. We also tested the hypothesis that cells embedded in floating mucilage fall on the underlying substratum, where their abundance depends on water flow. To this aim, in the field we manipulated the presence of floating mucilaginous aggregates in cages with different levels of exposure to winds. The abundance of C. taylorii cells on the substratum under cages with mucilage was compared with that of two control treatments: cages without mucilage and mucilage in still water, in the field and lab, respectively. The results suggested that mucilage can represent an excellent strategy for the species to disperse, as C. taylorii cells fall from the floating mucilage and, if the water flow is unimportant, settle on hard substrata just underneath the cage. This study enriches the portfolio of knowledge of the dispersal strategies of microalgae and contributes to the understanding of the spread of invasive species. 相似文献
97.
为了研究北极微藻对不同环境温度的适应性,对分离自北极王湾地区的三种微藻-玛氏骨条藻(Skeletonema marinoi)、小球藻(Chlorella sp.)和衣藻(Chlamydomonas sp.)在不同温度条件下(0℃、4℃和8℃)的生长曲线和抗氧化酶系统进行了测定.结果表明微藻对温度的适应性因种而异:玛氏骨条藻在4℃具有最快生长速率,最高的超氧化物歧化酶(SOD)和过氧化氢酶(CAT)酶活性,及最低的丙二醛(MDA)含量;小球藻的最快生长速率及酶活均在8℃时,MDA含量最低值出现在0℃;衣藻生长情况相差不大,MDA含量的最低值出现在8℃.抗氧化酶系统变化规律也因藻种及温度而异--在0℃与4℃变化时,玛氏骨条藻抗氧化酶系统的三个指标的差异极显著(P<0.01);在0℃与8℃变化时,玛氏骨条藻与小球藻的SOD活性的差异显著(P<0.05),其余两个指标差异不显著;衣藻在三个温度下的三个指标差异均不显著.总体而言,三种藻对三个温度的适应性均较好:其MDA的含量均较低,三种藻各自具有独特的生理代谢机制来适应不同的温度环境. 相似文献
98.
Five marine microalgae (Tetraselmis chuii, Rhodomonas salina, Chaetoceros sp., Isochrysis galbana (T-iso) and Nannochloropsis gaditana), in the same biovolume quantity, were exposed to 72h growth-inhibition tests with atrazine and LAS. In all cases, the inhibition effect of atrazine was higher than that of LAS up to two orders of magnitude higher in the case of T. chuii. In a second part of the study, initial cellular densities for each microalga strain and fixed organic compound concentration were varied, and results show density has a clear influence in growth inhibition tests. Finally, the sum of all data obtained in the study was expressed in terms of "toxic cellular quota" (mass of chemical substance per cell). The result was a sigmoid curve with a good fit, including the two main factors in toxicity tests, initial cellular density and contaminant concentration. This toxic cellular quota exhibits a general tendency to increase with cell volume/size. 相似文献
99.
海洋微藻中脂肪酸的气相色谱分析 总被引:19,自引:3,他引:16
本文以正十九碳酸作内标,用HCI-CH3OH对海洋微藻进行抽提酯化后做毛细管气相色谱分析。方法的重现性各脂肪酸的相对偏差为0.3%-11.6%,回收率为85.7%-103.3%,仪器稳定性的相对偏差为0.2-3.1%。。 相似文献
100.
本文报道了4种微藻不同浓度对方斑东风螺幼虫生长和变态的影响.结果表明,幼虫对4种微藻都能摄食,当投喂不同浓度的牟氏角毛藻、湛江叉鞭金藻时,摄食角毛藻(20×104cells/cm3)生长最快达77.9μm/d、变态率52.5%;摄食金藻(20×104cells/cm3)变态率最高达59.0%、生长速度70.4μm/d,随金藻浓度的上升,幼虫生长速度和变态率都上升.投喂不同浓度的青岛大扁藻时,最高变态率是24.4%(1×104cells/cm3),最快生长速度是59.3μm/d(7×104cells/cm3),随扁藻浓度的上升,幼虫的生长速度上升而变态率下降.摄食云微型藻幼虫生长缓慢,浮游期全部死亡.幼虫单独摄食角毛藻、金藻和扁藻,其首次出现变态个体的日龄分别是10、11、14d,而完成变态的日龄分别是22~23d、21~23d和26~28d.比较上述4种微藻,角毛藻和金藻是方斑东风螺幼虫的最适饵料,根据大水体人工育苗的具体条件,合适浓度应为角毛藻(5~10)×104cells/cm3,金藻(10~15)×104cells/cm3.而扁藻不宜单独投喂,作为辅助饵料较合适. 相似文献