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排序方式： 共有75条查询结果，搜索用时 15 毫秒
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This study is part of a project aiming to validate the use of the intertidal shanny Lipophorys pholis as a sentinel species in pollution monitoring in NW European marine ecosystems. To this end, a characterisation of acethylcholin (AChE), butyrylcholin (BChE) and propionylcholin (PrChE) esterases in L. pholis muscle was performed and the results indicated that AChE was predominant. Furthermore, the use of eserine sulphate and BW284c51 (0.64–800 μM), and iso-OMPA (0.08–16 mM), confirmed the measurement of true cholinesterases (ChEs) as well as the presence of pseudocholinesterases. The field application of these markers to L. pholis, sampled in seven locations along the Portuguese coast, revealed that fish were likely to be affected by neurotoxic compounds. This was indicated by the significant depletion of AChE (p < 0.05) in animals collected at urban and industrialised sites, compared with those from reference locations. The inclusion of a marker of effect, measured as lipid peroxidation levels in muscle tissue, also revealed the existence of site differences. Overall, the study further validates the utility of L. pholis in pollution monitoring studies. 相似文献
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Juvenile grey mullet (Chelon labrosus) were fed either a basal (4.4 mg Cu/kg dry wt) or high-Cu diet (2400 mg Cu metal/kg dry wt) for 10 weeks to assess the relationship between growth and Cu-induced oxidative damage. No mortalities were observed, but growth rate and food intake were reduced by 43 and 29%, respectively, in the high-Cu group. This was not only attributed to peroxidative damage of the food which reduced food intake (palatability), but also to direct effects of hepatic lipid peroxidation. Hepatic α-tocopherol concentrations were 63% lower, while malondialdehyde (MDA) increased by 304% in mullet fed a high-Cu diet for 67d. Cu-exposure reduced apparent α-tocopherol retention by 420%. Hepatic Fe and Zn levels fell, while Cu increased (p < 0.05). The results show that oral Cu exposure induces oxidative stress in grey mullet. Quantification of lipid peroxidation (rancidity) in the food, reflecting palatability, is essential to differentiate the direct toxic effects of Cu on growth from the secondary influences of reduced food intake. 相似文献
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You Ah Kim Chang Suk Kong Young Ran Um Jung Im Lee Taek Jeong Nam Youngwan Seo 《Ocean Science Journal》2008,43(1):31-37
As a part of an ongoing search for antioxidants frodm marine sources, antioxidant activities of 24 kinds of seaweeds (4 green
algae, 8 brown algae, and 12 red algae) were investigated. The seaweeds were extracted by acetone/ dichloromethane and methanol,
respectively. The antioxidant properties of both extracts were evaluated using four different activity tests, including degree
of occurrence of intracellular reactive oxygen species (ROS), NO, lipid peroxidation, and GSH (glutathione) in mouse macrophage
Raw 264.7 cells. The levels of intracellular reactive oxygen species (ROS) and GSH were measured using 2’,7’-dichlorofluorescin
diacetate (DCF-DA) and monobromobimane as fluorescence probe, respectively. Moreover, the generation of NO and lipid peroxidation
products were determined by each method based on the Griess reaction and TBARS assay. Solvent extracts from seaweeds such
asScytosiphon lomentaria, Prionitis cornea, Laruencia okamurae,Callophyllis japonica, Sargassum horneri, Dictyopteris divaricat a,Lomentaria catenata, Corallina confuse, Ishige okamurae, andAhnfeltiopsis flabelliformi exhibited high antioxidant activities in cellular oxidizing systems. 相似文献
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Rui Company Angela Serafim Richard Cosson Aline Fiala-Médioni David R. Dixon & Maria João Bebianno 《Marine Ecology》2007,28(1):93-99
The vent mussel Bathymodiolus azoricus is the dominant member of the Northern Mid‐Atlantic Ridge (MAR) hydrothermal megafauna, and lives in an environment characterized by temporal and spatial variations in the levels of heavy metals, methane and hydrogen sulphide, substances which are known to increase reactive oxygen species levels in the tissues of exposed organisms. To evaluate the effects of two contrasting hydrothermal environments on the antioxidant defence system of this vent mussel species, a 2‐week transplant experiment was carried out involving mussels collected from the relatively deep (2300 m), and chemical rich, Rainbow vent field. These were transplanted to the shallower (1700 m), and relatively less toxic, Lucky Strike vent field. To achieve this objective, levels of superoxide dismutase, catalase (CAT), total glutathione peroxidase (GPx), selenium‐dependent glutathione peroxidase and lipid peroxidation (LPO) were measured in the gills and mantle tissues of resident and transplant mussels before and after the transplant experiment. With the exception of CAT, the gills of the transplanted mussels had significantly higher antioxidant enzyme activity compared with the basal levels in the donor (Rainbow) and recipient (Lucky Strike) populations; whereas the antioxidant enzyme levels in the mantle tissues of the transplants reflected the baseline levels of activity in the native Lucky Strike mussels after 2 weeks. In contrast, LPO levels were significantly higher in both tissue types in the transplants than in either the source or the recipient populations, which suggested a response to hydrostatic pressure change (note, the transplant animals were brought to the surface for transportation between the two vent fields). The fact that the Rainbow mussels survived the transplant experience indicates that B. azoricus has a very robust constitution, which enables it to cope behaviourally, physiologically and genetically with the extreme conditions found in its naturally contaminated deep‐sea environment. 相似文献
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In the context of a multidisciplinary study to determine current and past ecosystem health and the relative contributions of sources of organic matter (marine vs. terrestrial and natural vs. anthropogenic input), sterols were determined in plankton, settling particles and sediments from Trinity Bay, Newfoundland, a sub-polar Atlantic Ocean ecosystem. The centric diatoms Chaetoceros spp., Thalassiosira spp. and Leptocylindrus danicus were all prominent in the plankton samples, and centric diatoms predominated in the settling particles. Plankton samples contained 0.4±0.4 mg/g dw (1995) or 1.4±1.3 mg/g dw (1996) total sterols, with cholesta-5,24-dien-3β-ol (mean 26% of total sterols), cholest-5-en-3β-ol (24%) and cholesta-5,22(E)-dien-3β-ol (13%) chief among these, denoting diatom and zooplankton sources. In settling particles, the prominence of cholesta-5,24-dien-3β-ol (24%), cholest-5-en-3β-ol (24%), cholesta-5,22(E)-dien-3β-ol (13%) and 24-methylcholesta-5,22(E)-dien-3β-ol (9%) again suggested mainly marine sources. The sterol composition of plankton and settling particles from different sampling periods showed a high degree of consistency. Higher plant C29 sterols (notably 24-ethylcholest-5-en-3β-ol, 9–26%) were prominent in sediments from both inshore and offshore sites. No decreasing trend in total or individual sterols was observed down the 30-cm sediment cores, suggesting good overall preservation. No 5β-stanols such as 5β-cholestan-3β-ol (coprostanol) were detected in offshore sediments, plankton or settling particles, with only low levels (5β-cholestan-3β-ol max. 4.4%, 5β-cholestan-3α-ol max. 5.1%) in certain inshore sediments. This suggests that raw sewage discharges in rural Newfoundland are being efficiently degraded or dispersed, or that inputs are highly localized. Source apportionation of organic matter in the sediment samples based on sterol composition was attempted. This highlighted the large terrestrial contribution to the sterols in marine sediments (up to 58% of sterols inshore, 24% offshore) and suggests either degradation or effective recycling of marine sterols. 相似文献
29.
研究了培养液中不同锰离子浓度对斜生栅藻(Scenedesmus obliquus)DHD-3 的生长、油脂积累以及脂肪酸组成的影响。结果表明, 培养液中不同初始浓度的锰离子对斜生栅藻早期叶绿素积累和生长会产生一定的调节作用, 过高或过低的锰离子都不利于斜生栅藻细胞内叶绿素的积累、微藻的生长和油脂的积累。经过14 d 培养后, 当初始锰离子的添加量为2.72 mg/L 时, 斜生栅藻的生物量和细胞内油脂含量分别达到2.9 g/L 和细胞干重的55.1%, 细胞内油脂含量比对照组提高了11%; 同时, 单位水体中油脂的产量达到了1.6 g/L, 比对照组提高了14%, 但改变锰离子的初始浓度并不对斜生栅藻脂肪酸的组成产生明显影响。 相似文献
30.
