排序方式: 共有64条查询结果,搜索用时 15 毫秒
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施用不同氮源对球等鞭金藻3011生长的影响 总被引:1,自引:0,他引:1
本实验通过以硝酸钠为氮源作为对照,研究施用氯化铵、硝酸铵和尿素对等鞭金藻3011生长的影响。从等鞭金藻的两个生长指标:藻细胞密度、pH来反映等鞭金藻3011的生长情况。经生物统计分析表明,在培养的前3天实验组和对照组的细胞密度差异性不显著(P>0.05),第4天到后期阶段天两组的细胞密度差异性显著(P<0.05)。由此结果表明以硝酸铵做氮源时对球等鞭金藻3011生长的效果最佳,藻细胞密度显著高于其他氮源,其次为硝酸钠和尿素,氯化铵的效果最差(P<0.05)。 相似文献
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两种藻类饲喂中华哲水蚤的繁殖差异 总被引:1,自引:0,他引:1
通过室内实验研究了中华哲水蚤摄食三角褐指藻(Phaeodactylumtricornutum)和球等鞭金藻(Isochrysis galbana)后产卵率、孵化率变化。22d的实验时间,摄食三角褐指藻的中华哲水蚤平均产卵率为0.24±(0.07)/d,雌体存活率较低,摄食球等鞭金藻的产卵率为7.84±(1.12)/d,雌体存活亦较高。不论在藻类溶出液和过滤海水中摄食三角褐指藻后所产的卵孵化率都低于摄食球等鞭金藻者。这表明对照球等鞭金藻相比,硅藻三角褐指藻对中华哲水蚤产卵和孵化都存在明显的抑制作用。脂肪酸分析结果显示,在三角褐指藻细胞内,对桡足类繁殖十分重要的多不饱和脂肪酸(PU-FAs)和特定脂肪酸(ω3,ω6)的含量皆较低。 相似文献
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María Concepción Lora-Vilchis Beatriz Cordero-Esquivel & Domenico Voltolina 《Aquaculture Research》2004,35(11):1086-1091
Survival, growth (length and weight), development, proximate composition, and energy content of Artemia franciscana fed for 7 days with Isochrysis sp. (TISO) or with Chaetoceros muelleri (CHGRA) were compared to evaluate the food value of these microalgae. Mean daily survival was not significantly different, and ranged from 86% to 93%. Diet‐related differences in growth were noted from the third day, and mean final dry weights (DWs) were 171 and 327 μg ind?1 for Artemia fed TISO and CHGRA respectively. Rates of development were different between diets, with a higher developmental index for Artemia fed TISO before day 3, and a higher index for Artemia fed CHGRA for the rest of the experiment. Chemical analysis showed that carbohydrates decreased to approximately 35% of the initial value in Artemia during the first 24 h, after which they remained approximately stable and similar with both diets. In percentage of total DW, lipids and proteins remained close to their respective initial values, but A. franciscana fed TISO had a higher ash content. A major difference between the two microalgae was the higher protein content of TISO, but this did not result in better growth. Of the two, TISO was richer in docosahexaenoic acid, which might explain the initial faster development, but CHGRA was a better source of eicosapentaenoic acid, which is the most probable explanation of the higher food conversion index, specific growth rate, and energy gain of A. franciscana fed this algae. 相似文献
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A.I. Campa-Crdova A. Luna-Gonzlez F. Ascencio E. Corts-Jacinto C.J. Cceres-Martínez 《Aquaculture (Amsterdam, Netherlands)》2006,260(1-4):145-150
This study focused on determining the effects of antibiotics on microalgae used as food for scallop larvae. Six different dose levels of chloramphenicol, erythromycin, and furazolidone were added to cultures of Isochrysis galbana and Chaetoceros gracilis. An in vivo experiment was subsequently conducted to determine the effect of chloramphenicol and erythromycin on larval survival of the Pacific calico scallop Argopecten ventricosus in tanks and on the population of its associated bacteria. Results showed that growth of I. galbana was not significantly affected by chloramphenicol or erythromycin at the test doses of 0.5, 1.0, 3.0, 6.0, 9.0, and 12.0 mg/l. C. gracilis was significantly sensitive to erythromycin and chloramphenicol at doses higher than 0.5 and 3.0 mg/l, respectively. Furazolidone inhibited the growth of both I. galbana and C. gracilis at all test doses. Results showed that exposure of scallop larvae to a dose of 6 mg/l chloramphenicol or erythromycin did not significantly affect growth of I. galbana, significantly enhanced survival of the scallop larvae, and inhibited the growth of Vibrio spp. in tanks. This study demonstrated the adverse effect of chloramphenicol, erythromycin and furazolidone on I. galbana and C. gracilis microalgae but the positive effect on survival of the scallop larvae, decreasing associated bacterial population. 相似文献
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对等鞭藻 30 11(Isochrysisgalbana 30 11)、等鞭藻塔溪堤品系 (TahitianIsochrysisgalbana)和绿色巴夫藻 (Pavlovaviridisai) 3株微藻种进行培养。NaHCO3的质量浓度分别为 0 ,2 0 0 ,4 0 0 ,80 0 ,12 0 0和 16 0 0mg/L ,培养温度 (2 2± 1)℃ ,盐度 2 8,光照强度 50 0 0lx。结果表明 ,NaHCO3的浓度对 3株微藻生长的影响差异显著 ,经过 6d的培养 ,培养液中不加NaHCO3、但连续充气组中 3株微藻的细胞浓度都达到最大值 ;除充气不加NaHCO3组外 ,3株微藻的细胞浓度都在NaHCO316 0 0mg/L组中达到最大值。 相似文献
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研究了小新月菱形藻(Nitzschiaclosteriumf.minutissima)(MACC/B228)和等鞭金藻8701(IsochrysisgalbanaParke8701)(MACC/H060)在4种光照条件下的生长情况,以及不同光强下、不同时期收获的藻细胞中总脂和碳水化合物含量的变化。结果表明,小新月菱形藻在光强70μmol·s-1·m-2时细胞分裂频率(μ)最大,最适光强70~140μmol·s-1·m-2;260μmol·s-1·m-2光强能导致细胞分裂频率变慢,指数期缩短。等鞭金藻8701在光强140μmol·s-1·m-2时μ值最大,260μmol·s-1·m-2下略有降低。2种藻均在低光下脂肪含量多,小新月和等鞭金藻脂肪含量分别占干重的25.5%~35.3%和28.3%~37.5%;而碳水化合物含量少,分别占干重的5.5%~18.2%、3.9%~11.4%;在高光强下相反。不考虑光照条件的影响,2种藻细胞内碳水化合物的含量均在静止期达到最大,分别占干重的18.98%和23.32%。小新月菱形藻在70μmol·s-1·m-2光强下的指数期细胞有最大的脂肪含量,等鞭金藻的最高脂肪含量出现于光强20μmol·s-1·m-2下指数末期的细胞中。二者在光强140μmol·s-1·m-2下生长且进入静止期时均可获得较大生物量,同时细胞的脂肪和碳水化合物的含量也处于较高水平。 相似文献
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To develop greener extraction alternatives for microalgae biomass, ultrasound assisted extraction (UAE) and pressurized liquid extraction (PLE) with different biobased solvents were investigated, demonstrating that both techniques are useful alternatives for algal lipid extraction. Specifically, Nannochloropsis gaditana lipids were extracted by UAE and PLE at different temperatures and extraction times with sustainable solvents like 2-Methyltetrahydrofuran (2-MeTHF) and its mixtures with ethanol and other alcohols. The best oil yields for both PLE and UAE of N. gaditana were achieved with the mixture of 2-MeTHF:ethanol (1:3), reaching yields of up to 16.3%, for UAE at 50 °C and up to 46.1% for PLE at 120 °C. Lipid composition of the extracts was analyzed by HPLC-ELSD and by GC-MS to determine lipid species and fatty acid profile, respectively. Different fractionation of lipid species was achieved with PLE and solvent mixtures of different polarity. Thus, for the extraction of glycolipids, ethanolic extracts contained higher amounts of glycolipids and EPA, probably due to the higher polarity of the solvent. The optimized method was applied to microalgae Isochrysis galbana and Tetraselmis chuii showing the potential of mixtures of biobased solvents like 2-methyl-THF and ethanol in different proportions to efficiently extract and fractionate lipids from microalgal biomass. 相似文献