Seasonal Changes in the Biochemical Composition of the Edible Sea Urchin Paracentrotus lividus Echinodermata: Echinoidea in a Lagoonal Environment   总被引：1，自引：0，他引：1  

C. Fernandez 《Marine Ecology》1998,19(1):1-11

Abstract. Monthly soluble and insoluble protein, carbohydrate, lipid and ash levels and energetic content were measured in tissues of Paracentrotus lividus adults living in a lagoonal environment over a 1-year period to increase our understanding of resource allocation to the different tissues. The biochemical composition of P. lividus individuals in this environment is similar to that observed in other environments. The gonad and gut contained a high level of proteins soluble or insoluble, a lesser amount of lipids and, finally, a low level of carbohydrates. The main component of the test was ash, followed by protein levels. The lipid and carbohydrate levels in the test were very low. Seasonal variability in the biochemical composition of the different body parts was observed. In the gonad, an increase in the level of lipids was recorded concomitant to an increase in gonad weight. The lipids and carbohydrates, after an initial increase, decreased with the maturation of the gonad. The biochemical variations observed in the gut seem to be linked to both the reproductive cycle and the sea urchin's trophic activity. Variability in the test was low and irregular for all of the observed biochemical components. As P. lividus is an important member of the benthic community in the Urbinu lagoon, this echinoid represents an important store of materials and energy within this lagoonal environment.  相似文献   

Variability in the speciation of iron in the northern North Sea     

Martha Gledhill  Constant M. G. van den Berg  Rob F. Nolting  Klaas R. Timmermans 《Marine Chemistry》1998,59(3-4)

Variations in the speciation of iron in the northern North Sea were investigated in an area covering at least two different water masses and an algal bloom, using a combination of techniques. Catalytic cathodic stripping voltammetry was used to measure the concentrations of reactive iron (Fe_R) and total iron (Fe_T) in unfiltered samples, while dissolved iron (Fe_D) was measured by GFAAS after extraction of filtered sea water. Fe_R was defined by the amount of iron that complexed with 20 μM 1-nitroso-2-napthol (NN) at pH 6.9. Fe_T was determined after UV-digestion at pH 2.4. Concentrations of natural organic iron complexing ligands and values for conditional stability constants, were determined in unfiltered samples by titration. Mean concentrations of 1.3 nM for Fe_R, 10.0 nM for Fe_T and 1.7 nM for Fe_D were obtained for the area sampled. Fe_R concentrations increased towards the south of the area investigated, as a result of the increased influence of continental run off. Fe_R concentrations were found to be enhanced below the nutricline (below 40 m) as a result of the remineralisation of organic material. Enhanced levels of Fe_T were observed in some surface samples and in samples collected below 30 m at stations in the south of the area studied, thought to be a result of high concentrations of biogenic particulate material and the resuspended sediments respectively. Fe_D concentrations varied between values similar to those of Fe_T in samples from the north of the area to values similar to those of Fe_R in the south. The bloom was thought to have influenced the distribution of both Fe_R and Fe_T, but less evidence was observed for any influence on Fe_R and Fe_D. The concentration of organic complexing ligands, which could possibly include a contribution from adsorption sites on particulate material, increased slightly in the bloom area and in North Sea waters. Iron was found to be fully (99.9%) complexed by the organic complexing ligands at a pH of 6.9 and largely complexed (82–96%) at pH 8. The ligands were almost saturated with iron suggesting that the ligand concentration could limit the concentration of iron occurring as dissolved species.  相似文献   

Production of methyl bromide and methyl chloride in laboratory cultures of marine phytoplankton II     

M. G. Scarratt  R. M. Moore 《Marine Chemistry》1998,59(3-4)

Methyl halides (monohalomethanes), especially methyl bromide, are known to contribute significantly to ozone destruction in the stratosphere. Budgets of natural and anthropogenic methyl bromide suggest that marine organisms may be the source of a significant proportion of the total global production. Since phytoplankton are abundant in surface waters, they are obvious candidates. Cultures of nine phytoplankton species were grown in CO₂-enriched, nitrate-limited medium in sealed glass vessels. Species tested include Chaetoceros calcitrans, Isochrysis sp., Porphyridium sp., Synechococcus sp., Phaeodactylum tricornutum, Tetraselmis sp., Prorocentrum sp., Emiliania huxleyi and Phaeocystis sp. Methyl bromide (CH₃Br) and methyl chloride (CH₃Cl) concentrations were determined by bubbling the cultures with high-purity air, cryotrapping the effluent and analyzing it on a gas chromatograph with an electron capture detector. The Phaeocystis sp. samples were monitored with GCMS. Cell population, bacterial population, Chl a, pH, and nitrate concentration were monitored for periods of at least two weeks. CH₃Cl was produced by all cultures. CH₃Br was absent in Tetraselmis sp. and Isochrysis sp. cultures, but present in all the others. Methyl iodide (CH₃I) was present in most cultures but could not be quantified due to analytical limitations. CH₃I and CH₃Br production was fastest in stationary phase and continued long after cell division had ceased. Axeic cultures of Phaeocystis sp. achieved almost identical production rates of CH₃Cl and CH₃Br as xenic cultures of the same species. Species from tropical waters had faster CH₃Cl and CH₃Br production rates than temperate species. Scaling the observed production rates using global standing stock estimates for Chl a and particulate nitrogen indicate that phytoplankton can account for only a fraction of the CH₃Cl and CH₃Br believed to be produced in the ocean. Calculations based on the estimated global biomass of Phaeocystis sp. and E. huxleyi blooms show that their contribution is insignificantly small.  相似文献   

厦门海区潮间带海洋动植物共附生微生物的抗菌活性   总被引：20，自引：0，他引：20  

郑忠辉  陈连兴 《台湾海峡》1998,17(4):439-444

从厦门海区潮间带石纯、浒苔、江蓠、海兔、海葵及鲨鱼肠道分离得２８９株共附生微生物,以８种敏感菌为指示菌,从中获得拮抗活性的幼苗２８株,放线菌１７株,真菌８株。拮抗细菌以假单胞菌（３９％）、弧菌（２５％）和芽直菌（１４％）为主,主要为抗革兰氏阳性细菌,抗真菌的菌株比例较低。拮抗放线菌分属于链霉菌和小单孢菌,其抗革兰氏阳性菌、阴性菌和真菌的菌株比例分别为６５％、４７％和２３％。拮抗真菌分青霉属和芽枝霉  相似文献   

Induction of heat shock protein (hsp)60 in Isochrysis galbana exposed to sublethal preparations of dispersant and Prudhoe Bay crude oil     

M. F. Wolfe  H. E. Olsen  K. A. Gasuad  R. S. Tjeerdema  M. L. Sowby 《Marine environmental research》1999,47(5):517

Adaptation to sublethal exposure to crude oil by phytoplankton is poorly understood. Use of chemical dispersants for oil spill remediation increases petroleum hydrocarbon concentrations in water, while exposing marine organisms to potentially toxic concentrations of dispersant. Heat shock proteins (hsps) have been found to serve as an adaptive and protective mechanism against environmental stresses. The objective of this project was to examine the induction of hsps in Isochrysis galbana, a golden-brown algae, following exposure to the water-accommodated fraction (WAF) of Prudhoe Bay crude oil (PBCO) and PBCO chemically dispersed with Corexit 9527® (dispersed oil: DO). Initial experiments using ³⁵S-labeled amino acids and 2-dimensional electrophoresis with subsequent western blotting identified and confirmed hsp60, a member of the chaperonin family of stress proteins, as being efficiently induced by heat shock in this species. One-dimensional SDS PAGE and western blotting, with hsp60 antibodies and chemiluminesence detection, were used to quantitate hsp60 following exposure to a range of environmental temperatures and concentrations of WAF and DO preparations. I. galbana cultured in 22 parts per thousand (‰) salinity showed a statistically significant increase (p<0.05) in hsp60 after exposure to 25, 30, and 35°C for 1 h compared to controls (20°C), while 34‰ cultures showed no significant increase in hsp60 with increasing temperature. Cultures (22 and 34‰) exposed to varying doses of WAF and DO exhibited statistically significant (p<0.05) increases in levels of hsp60 in all cases. A dose-related response was observed in all exposures (r²≥0.90) with the exception of 34‰ WAF. In independent exposures, a dose-related hsp60 response to naphthalene, a relatively abundant water-soluble aromatic hydrocarbon, was observed in both 22 and 34‰ cultures. Results of this study are consistent with previous studies in other species documenting increases in hsp60 levels with exposure to xenobiotics. Further studies are investigating the protective function of hsp60 against the toxic effects of exposure to WAF and DO preparations.  相似文献   

一株大口黑鲈源ST-873型肺炎克雷伯菌(Klebsiella pneumoniae)的分离鉴定及生物学特性研究     

曹馨月  黄嘉怡  杜诗钰  侯天牧  项维  郜卫华  张付贤 《海洋与湖沼》2023,3(3):836-847

从患腹水病大口黑鲈(Micropterus salmoides)的头肾、脾脏、肝脏组织中分离到一株优势菌,生长出圆形、边缘整齐的灰白色黏液状菌落;染色镜检可见短粗、卵圆形、有荚膜的革兰氏阴性杆菌。结合形态、生理生化特征、16S rRNA基因序列分析鉴定为肺炎克雷伯菌(Klebsiella pneumoniae),MLST分析进一步确定其为ST-873型,与ST-65型聚为一支;该菌株携带aere、alls、wca和ybt四种毒力基因,具有溶血活性;人工感染大口黑鲈,发现患病鱼呈现腹水等与自然发病类似的症状,且病鱼内脏的分离菌株与攻毒菌株相同;经统计,其LD50为3.4×10⁷ CFU/mL,具有中等生物被膜形成能力。耐药性分析结果显示,该菌株携带bla-shv、sul2、aadA和tetB四种耐药基因,对β-内酰胺类、氨基糖苷类、喹诺酮类、黏菌素类药物敏感,对四环素类、磺胺类、林可酰胺类、利福霉素类耐药;中药三七、款冬花对分离菌株有明显抑制作用。研究探明了大口黑鲈腹水病的主要病原,可为鱼源肺炎克雷伯菌的诊断和防治提供科学依据和数据参考。  相似文献   

东风螺、弯竹蛏和斑节对虾的壳基质蛋白组学分析          下载免费PDF全文

张爱华  卫子嫣  姚宇阗  张道锋  黄建科  刘闯 《海岸工程》2022,41(3):258-267

从软体动物中的腹足纲、双壳纲以及节肢动物中的甲壳纲分别选取了3种中国沿海常见的品种——东风螺、弯竹蛏、斑节对虾,提取并分析它们的壳基质蛋白。利用液相色谱串联质谱（LC-MS/MS）技术对蛋白质组学进行分析发现特定的蛋白质具有明显的种属差异：①N66蛋白（一种碳酸酐酶）通常存在于弯竹蛏中,但不存在于东风螺和斑节对虾中,揭示N66蛋白质具有特异性,在未来的物种鉴定中可能具有重要的参考意义;②角质层蛋白AM1199和CP14.6存在于斑节对虾的表皮结构中,在东风螺和弯竹蛏中未检测到;③血蓝蛋白同时在3种动物外壳的基质蛋白中被鉴定出来,揭示了其在不同物种的外壳形成与发育过程中的重要作用。该研究为壳基质蛋白在软体动物或节肢动物外壳中的鉴定提供了基础,也为探索不同物种的生物矿化过程提供了重要参考。  相似文献   

Origin and depositional environments of source rocks and crude oils from Niger Delta Basin: Carbon isotopic evidence     

《China Geology》2020,3(4):602-610

Thirty-nine crude oils and twenty-one rock samples from Niger Delta Basin, Nigeria have been characterized based on their isotope compositions by elemental analysis-isotope ratio mass spectrometry and gas chromatography-isotope ratio mass spectrometry. The bulk carbon isotopic values of the whole rock extracts, saturate and aromatic fractions range from –28.7‰ to –26.8‰, –29.2‰ to –27.2 ‰ and –28.5 ‰ to –26.7 ‰, respectively while the bulk carbon isotopic values of the whole oils, saturate and aromatic fractions range from –25.4 ‰ to –27.8 ‰, –25.9 ‰ to –28.4 ‰ and –23.5 ‰ to –26.9 ‰, respectively. The average carbon isotopic compositions of individual alkanes (nC₁₂-nC₃₃) in the rock samples range from –34.9‰ to –28.2‰ whereas the average isotopic values of individual n-alkanes in the oils range from –31.1‰ to –23.8‰. The δ¹³C isotope ratios of pristane and phytane in the rock samples range from –29.2 ‰ to –28.2 ‰ and –30.2 ‰ to –27.4 ‰ respectively while the pristane and phytane isotopic values range from –32.1‰ to –21.9‰ and –30.5‰ to –26.9‰, respectively. The isotopic values recorded for the samples indicated that the crude oils were formed from the mixed input of terrigenous and marine organic matter and deposited under oxic to sub-oxic condition in lacustrine-fluvial/deltaic environments. The stable carbon isotopic compositions were found to be effective in assessing the origin and depositional environments of crude oils in the Niger Delta Basin.  相似文献   

三疣梭子蟹(Portunus trituberculatus)冻藏过程中肌肉蛋白质生化特性的变化     

黄琳  张莉  武丹露 《海洋科学》2017,41(6):41-47

以三疣梭子蟹肌肉基本营养成分、蛋白质组成、肌原纤维蛋白含量、Ca~(2+)-ATPase活性、总巯基含量、二硫键含量以及肌原纤维蛋白的SDS-PAGE分析作为指标,研究了三疣梭子蟹在不同冻藏温度下肌肉蛋白质生化特征的变化。结果表明,三疣梭子蟹是典型的高蛋白食品;随着冻藏时间的延长,水溶性蛋白含量先增加后减少,盐溶性蛋白和不溶性蛋白含量逐渐减少,碱溶性蛋白含量逐渐增加;肌原纤维蛋白含量、Ca~(2+)-ATPase活性、总巯基含量随着冻藏时间的延长,均呈现下降趋势,而二硫键含量则呈上升趋势,且–20℃和–40℃两组之间差异显著(P0.05)。SDS-PAGE分析结果表明,组成肌原纤维蛋白的各种蛋白质均有不同程度降解,且–20℃比–40℃组降解更明显。因此,–40℃冻藏对梭子蟹肌肉蛋白质生化特性的影响较小。  相似文献   

iTRAQ-based proteomic profiling of the marine medaka (Oryzias melastigma) gonad exposed to BDE-47     

C.C. Fong  Y.F. Shi  W.K. Yu  F. Wei  J.P. van de Merwe  Alice K.Y. Chan  R. Ye  Doris W.T. Au  Rudolf S.S. Wu  M.S. Yang 《Marine pollution bulletin》2014

A recent study demonstrated that 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) may have an adverse effect on the reproduction in marine medaka (Oryzias melastigma), but the molecular mechanisms remain largely unknown. In this study, we investigated the protein expression profiles of male and female gonads of O. melastigma exposed to dietary BDE-47 at two dosages (0.65 and 1.30 μg/g/day, respectively) for 21 days. Extracted proteins were labeled with iTRAQ and analyzed on a MALDI TOF/TOF analyzer, as results, 133 and 144 unique proteins were identified in testis and ovary, respective, and they exerted dose- and sex-dependent expression patterns. In testis, among the 42 differentially expressed proteins; down-regulation of histone variants and parvalbumins implicated BDE-47 may disrupt the spermatogenesis and induce sterility in fishes. In ovary, 38 proteins were differentially expressed; the elevation of vitellogenins and apolipoprotein A–I expression indicated BDE-47 acts as an estrogen-mimicking compound and led to reproductive impairment in O. melastigma.  相似文献