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Inhibitory effect of Salicornia europaea on the marine alga Skeletonema costatum
Dan Jiang,LingFeng Huang,YongQing Lin,LingLing Nie,SuLian Lv,TingYun Kuang,YinXin Li
Science China Life Sciences , 2012, DOI: 10.1007/s11427-012-4328-5
Abstract: Exploiting the negative biochemical interference between plants and algal species has been suggested as a method to control harmful algal blooms. In this work, we investigated the inhibitory effect of the salt marsh halophyte Salicornia europaea against the marine alga Skeletonema costatum. S. europaea suppressed the growth of S. costatum in a nutrient-sufficient co-culture system, indicating that the inhibition of algal growth was because of the phytotoxic effect of S. europaea, rather than nutrient competition. We tested aqueous and organic extracts from S. europaea roots against S. costatum. The organic extracts inhibited growth and affected the cell size and chlorophyll a content of S. costatum in a dose-dependent manner. Among the three tested organic extracts, the methanol extract had the greatest effects on S. costatum, followed by butanol extract, and then the chloroform extract. Two flavonoids, rutin and quercetin-3-β-D-glucoside, were identified in the methanol extract by high performance liquid chromatography. The concentration of rutin was much higher than that of quercetin-3-β-D-glucoside. In an algal bioassay, rutin inhibited the growth of S. costatum and the inhibitory effect increased with increasing rutin concentration and with decreasing initial algal density. Therefore, we concluded that S. europaea negatively affects the growth of S. costatum, and that rutin, a metabolite of S. europaea, may play a role in this inhibitory effect.
Evaluation of estuarinesurface waters effect on grouth of diatom Skeletonema costatum Avalia o do efeito das águas superficiais dos estuários dos rios Camboriú e Itajaí-a ú sobre o crescimento da diatomácea Skeletonema costatum
R. S. Macedo,L. R. R?rig,S. R. Urban,M. A. da Castro-Silva
Brazilian Journal of Aquatic Science and Technology , 2005,
Abstract: The Itajaí-A ú and Camboriú rivers are the main important water suppliers for domestic and agroindustrial use in Itajaí and Balneário Camboriú cities in southeastern coast of Brazil. The waste dispoasal by human activities in these estuaries may result in poor water quality and even prevent its use for these activities. In order to evaluate the effects of the human activities upon the estuaries water quality, this study was carried out to evaluate and compare the surface water quality in both estuaries, using a toxicological bioassay to mesure the effect of these waters in growth of marine microalgae Skeletonema costatum (Bacillariophyceae). The samples were colletcted from august of 2003 to march of 2004 in every two weeks at CEPSUL/IBAMA pier (in Itajaí-A ú estuary) and turistic pier (in Camboriú estuary). The physical and chemical characteristics of the samples were determined in situ. The samples were taken to laboratory and frozen for further use. After conducing the bioassay, the results show an increase in algal growth due to excess of nutrients in the samples of both estuaries. This result indicates water eutrophication, as reported in other studies. No effect in the growth of the species was observed for the samples collected in summer months. The samples of march of 2004 from Camboriú estuary were toxic to S. costatum. This result may be due to the disposal of treated wastewater from Balneário Camboriú wastewater treatment plant in the surface river water. The observed concentration effect (CEO) obtained for the samples of march were almost 50%. The CE50 calculated was 96,17% for one sample of march. In the present work, the use of microalgae toxicity test for mesure toxicity in environmental samples and its use as water eutrophication indicator were confirmed. The Itajaí-A ú and Camboriú rivers are the main important water suppliers for domestic and agroindustrial use in Itajaí and Balneário Camboriú cities in southeastern coast of Brazil. The waste dispoasal by human activities in these estuaries may result in poor water quality and even prevent its use for these activities. In order to evaluate the effects of the human activities upon the estuaries water quality, this study was carried out to evaluate and compare the surface water quality in both estuaries, using a toxicological bioassay to mesure the effect of these waters in growth of marine microalgae Skeletonema costatum (Bacillariophyceae). The samples were colletcted from august of 2003 to march of 2004 in every two weeks at CEPSUL/IBAMA pier (in Itajaí-A ú estuary) and turistic pier (
Comparison between Airlift Photobioreactor and Bubble Column for Skeletonema Costatum Cultivation  [cached]
Saranya Monkonsit,Sorawit Powtongsook,Prasert Pavasant
Engineering Journal , 2011, DOI: 10.4186/ej.2011.15.4.53
Abstract: The cultivation of diatom Skeletonema costatum was achieved in airlift photobioreactor and the system performance was compared to that of bubble column. The standard F/2 medium (Guillard’s medium) for typical diatom cultivation could only yield the best growth character when the silicon concentration increased 4 times the normal value. In terms of cell growth, the airlift photobioreactor provided better performance than the bubble column where the maximum cell concentration, specific growth rate, and productivity in the airlift were 4.6 x 106 cell mL-1, 0.07 h-1, and 6.4 x 104 cell s-1 compared with 1.8 x 106 cell mL-1, 0.04 h-1, and 2.2 x 104 cell s-1 in the bubble column of the same size (3L) and operated at the same aeration rate (superficial velocity = 1.5 cm s-1) and light intensity (34 μmol photons m 2 s 1). This was because the airlift photobioreactor allowed circulatory flow in the system which helps prevent cell precipitation and enhance light utilization efficiency. The optimal operating conditions in the airlift system which was found most optimal to cell growth were: the ratio between downcomer and riser cross sectional area (Ad:Ar) of 3.27, superficial gas velocity 1.5 cm s 1 and the light intensity 34 μmol photons m 2 s 1. Preliminary economical assessment on the cultivation of S. costatum in airlift system compared with that in bubble column was carried out, whereas the analysis for nutritional values of the obtained biomass indicated relatively high protein content.
Study on the Effect of Monochromatic Light on the Growth of the Red Tide Diatom Skeletonema Costatum  [PDF]
Hongli Miao, Lina Sun, Qingzhen Tian, Shanshan Wang, Jing Wang
Optics and Photonics Journal (OPJ) , 2012, DOI: 10.4236/opj.2012.23022
Abstract: Effects of light intensity and quality of three kinds of LED monochromatic lights (blue, green, and red) on the growth of Skeletonema costatum are investigated in batch culture conditions. Seven light intensities (20, 30, 40, 45, 50, 60 and 80 μmol·m-2·s-1) are used to evaluate the specific growth rate, spectrum absorption coefficient and saturated light intensity of LED monochromatic light. Results show that the growth rates of Skeletonema costatum increase with the enhanced light intensity; however, the light level beyond the saturation light intensity inhibited the growth of Skeletonema costatum. Compared with red and green light, the growth rate of Skeletonema costatum under blue light is higher within saturated light intensity, and saturated light intensity of LED monochromatic light is lower under blue light and higher under green light. It is concluded that under different monochromatic light, the saturated light intensity decreases and the growth rate increases with the increasing of spectrum absorption coefficient.
THE GRAZING OF AURELIA sp.1 ON SKELETONEMA COSTATUM AND PROROCENTRUM DONGHAIENSE
海月水母(Aurelia sp.1)对中肋骨条藻(Skeletonema costatum)和东海原甲藻(Prorocentrum donghaiense)摄食的研究

ZHENG Shan,SUN Xiao-Xia,SUN Song,
郑 珊
,孙晓霞,孙 松

海洋与湖沼 , 2012,
Abstract: The effects of different microalgal species and cell densities on the feedings of polyps, ephyrae and medusae of Aurelia sp.1 under controlled laboratory conditions were investigated. Two species of microalgae, Skeletonema costatum and Prorocentrum donghaiense, were used. Different microalgal species and cell densities had significant effects on the feedings of polyps, ephyrae and medusae. With the increasing of microalgal cell desities, the ingestion rates (IR) of polyps and ephyrae increased while the clearance rates (CR) decreased. The maximum IR of polyps on S. costatum and P. dong-haiense were 4623 and 4118 cells/(ind·h), respectively, while the maximum IR of ephyrae on S. costatum and P. dong-haiense were 174671 and 47218 cells/(ind·h), respectively. At similar microalgal cell densities, the IR of ephyrae on S. costatum were higher than those on P. donghaiense, and the IRof ephyrae were higher than those of polyps. The adaption of microalgae made IR of polyps increased about ten times. Medusae did not feed on S. costatum and P. donghaiense.
Evaluation of produced water toxicity from an oil maritime terminal through Skeletonema costatum toxicity tests
Aidar, Elizabeth;Sigaud-Kutner, Teresa C. S.;Bicega, Márcia C.;Schinke, Katya P.;Gianesella, Sania M. F.;Braga, Elisabete S.;
Brazilian Journal of Oceanography , 1999, DOI: 10.1590/S1679-87591999000200003
Abstract: the liquid effluent from an oil maritime terminal, with produced water as the main component, had its toxicity evaluated through toxicity tests with the diatom skeletonema costatum. two previously treated effluent samples (effluents a and b), were provided by petrobras for the experiments. both samples presented high salinity (67‰ for effluent a and 62‰ for effluent b) and low ph values (6.2), whereas total sulphide, phenol and nutrient content, dissolved/dispersed petroleum hydrocarbon concentration, bod and cod values were quite different from each other. during the toxicity experiment, three replicate flasks with samples for each treatment were exposed to a light radiation of 266μe m2 s-1 and maintained under a 10 h/14 h lightldark cycle, at a temperature of 24 :t 2oc. the ec50 values could not be accurately estimated for effluent a: 60 h and 132 h after starting the experiment they were below 3% and between 3-6% effluent concentration, respectively. synergistic effects between effluent toxicity and salinity on the growth of s. costatum were detected. the effluent b showed higher toxicity: the ec5o values were 0.17% and 0.40% of effluent concentrations, after 48 h and 96 h, respectively. these results evidenced the deleterious effects of residual organic compounds contained in the aqueous effluents from the oil terminal under the present pretreatment on s. costatum. in the light of the present data, the direct disposal ofthese effluents into s?o sebasti?o channel waters might be very hazardous to its indigenous biota.
Skeletonema cf.costatum Biogenic Silica Production Rate Determinated by PDMPO Method Skeletonema cf.costatum Biogenic Silica Production Rate Determinated by PDMPO Method  [PDF]
ZHANG Guicheng,LENG Xiaoyun,FENG Yuanyuan,LI Xia,SUN Jun
- , 2017,
Abstract: Diatoms are the only ecological phytoplankton that require silicic acid for growth.They are also the dominant contributor of ocean's total primary productivity.Generation and circulation with silica walls,which the siliceous organisms form,is an important component of the marine biological pump.It is crucial to the study of the operational mechanisms of biological pump with different sea areas.Moreover,it is the key link to the study of global silicon cycle.This paper introduces the basic mechanism of the formation of diatom silica walls and a new way of researching silicic acid metabolism,namely the 2-(4-pyridyl)-5-((4-(2-dimethylaminoethylaminocarbamoyl)-methoxy)phenyl)oxazole(PDMPO) dyeing method.Under a fluorescence microscope after excitation with bright green fluorescence,it can combine with silicic acid to form a complex into the Si deposition within diatom cells.The advantage of this method is that it can monitor the metabolism of silicate after adding PDMPO.For experimentation and sample collection in each of the specified time points,samples were determinated through the unutilized silicic acid,silica dissoluble intracellular and Si deposition within diatom cells,not only using hot alkaline digestions method but also PDMPO dyeing method.Results showed a good linear relationship between PDMPO fluorescent value and biogenic silica concentration.It was also indicated that PDMPO had no deleterious impact on Skeletonema cf.costatum growth for 34 h and was useful for tracking newly-deposited biogenic silica in diatoms' frustules
The effects of nitrate and phosphate on the growth and nitrate reductase activity of Skeletonema costatum
氮磷营养盐对中肋骨条藻生长及硝酸还原酶活性的影响

WANG Jin-hua,TANG Hong-jie,YANG Ru-jun,WANG Xiu-lin,
王金花
,唐洪杰,杨茹君,王修林

海洋科学 , 2008,
Abstract: The growth and nitrate reductase activity(NRA)of Skeletonema costatum were studied under different concentrations and structures of nitrate and phosphate in laboratory cultures.The results indicated that S.costatum is a nutrients-dependent species and the algae multiplied exponentially after adding nitrate or phosphate into the culture.The cell density in each group not only reached its maximum value in the fourth to fifth day after inoculation,but also showed a significant difference(P<0.01)to the control ...
Population dynamics of Skeletonema costatum in Zhelin Bay of Eastern Guangdong
粤东柘林湾中肋骨条藻(Skeletonema costatum)种群生态学

Huang Changjiang,Wang Chao,Dong Qiaoxiang,Lin Xiaoping,
黄长江
,王超,董巧香,林小苹

生态学报 , 2007,
Abstract: 于2000年5月~2004年12月对粤东大规模养殖区柘林湾的赤潮藻中肋骨条藻(Skeletonema costatum)种群的时空分布进行了长达5a的调查。结果表明,中肋骨条藻种群密度的周年变动模式基本为双峰型,平面分布没有显著的空间差异。调查期间,中肋骨条藻种群密度的站位实测值为0~1.4×107 cells/dm3,总均值为3.3×105 cells/dm3,占浮游植物总细胞数的67.1%,为调查海区第1优势种。在总共1045份样品中,有中肋骨条藻出现的样品数为1020份。其中,种群密度大于106 cells/dm3的样品有65份,大于107 cells/dm3则有4份。以大于106 cells/dm3为中肋骨条藻的赤潮密度标准,在调查期间至少于2000年、2003年发生4次赤潮。运用灰关联理论对中肋骨条藻种群密度与13个环境因子的关系进行排序分析发现,水温、pH值和浮游动物是影响柘林湾中肋骨条藻种群时空分布的关键因子。水温还与中肋骨条藻种群密度的对数值具极显著意义的线性关系,而达到赤潮密度的样品均落在24.5~32.0℃区间,即每年的5~9月份高温季节。由于柘林湾浮游动物的年高峰期也出现在高温季节,说明浮游动物摄食压力的存在可能是柘林湾中肋骨条藻赤潮发生的重要抑制因子。2004年调查海区中肋骨条藻种群密度和在浮游植物群落中的优势度骤然降低,可能与水体营养盐结构和Fe含量的变化有关。因此,长期调查与监测对于研究海湾生态学和赤潮发生机制是极为重要的。
AN ALTERNATIVE PROPOSAL: ACOUSTIC TECHNIQUES TO ASSES DETECTION AND MONITORING OF TOXIC ALGAL BLOOMS
Blanc,Silvia; Mosto,Patricia; de Milou,Marta E; Benítez,Carlos;
Gayana (Concepción) , 2004, DOI: 10.4067/S0717-65382004000200009
Abstract: an alternative methodology consisting in the application of acoustic techniques to asses detection and monitoring of toxic algal blooms is presented here. successive steps in this direction led to already reported results [blanc et al., 2000] achieved under the frame of a multidisciplinary research programme conducted in the argentinean naval service of research and development. first efforts were focused in the examination of the acoustical scattering behaviour of single-species cultures of skeletonema costatum. for this purpose a pulse-echo electronic equipment was developed, including home-made piezoelectric transducers with an operating frequency centred at 2.6 mhz. a slight modified johnson's fluid-sphere model was used. numerical abundance estimates from at-lab acoustic determinations of volume backscattering strengths were obtained. when they were compared with predicted values computed through the adopted model and traditional optical counting, satisfactory results were obtained. more recently, single cultures of dinoflagellates, namely, gymnodinium sp., were selected to enable a further stage of acoustic laboratory measurements. controlled observations of its optimum growth conditions along a six-months period have been performed. the effects of different patterns of light and temperature have been analysed. simultaneous work on modifying existing models of backscattering cross-sections to provide a realistic description of dinoflagellates physical properties is being performed
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