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991.
Linda A. Baldwin Edward J. Calabrese Paul T. Kostecki Jae-Ho Yang 《Fish physiology and biochemistry》1990,8(4):347-351
Peroxisomes are the sites for β-oxidation of long-chain fatty acids. The peroxisomal bifunctional enzyme (PBE) enoyl-CoA hydratase,
3-hydroxyacyl-CoA dehydrogenase catalyzes the second and third reactions of the β-oxidation system. Originally termed PPA-80
for peroxisome-proliferation associated 80,000 MW polypeptide, PBE levels are monitored to measure peroxisome proliferation
in rodents and other species. The quantity of a 79,000 MW polypeptide in the light mitochondrial fraction of the liver, as
analyzed by SDS-PAGE, increases when rainbow trout are exposed to peroxisome proliferating agents. This correlates with increases
in acyl-CoA oxidase activity and peroxisome volume density. In the present study, peroxisomal enoyl-CoA hydratase was purified
from trout liver and analyzed by immunoblotting with anti-PBE. A positive reaction with the 79,000 MW polypeptide band was
observed providing strong evidence that this is the bifunctional enzyme. 相似文献
992.
The influence of a dietary lipid source on growth, muscle fatty acid composition and erythrocyte osmotic fragility of hybrid tilapia 总被引:5,自引:0,他引:5
An 8-week feeding trial was conducted to determine the effects of various dietary lipids on the growth, tissue proximate composition, muscle fatty acid composition and erythrocyte osmotic fragility of red hybrid tilapia, Oreochromis sp. Five isonitrogenous and isoenergetic semipurified diets were supplemented with 10% of either cod liver oil (CLO), sunflower oil (SFO), crude palm oil (CPO), crude palm kernel oil (CPKO), or a combination of 5% CLO with 5% palm fatty acid distillates (PFAD), respectively. There were no significant effects (P > 0.05) of diet on growth but fish fed the CLO diet showed a significantly (P< 0.05) poorer feed efficiency ratio compared to fish fed the CPO diet. Lipid deposition in fish muscle was mostly similar among fish fed the various diets but bone ash was significantly higher in fish fed the CPO and CPKO diets. Muscle lipids of fish fed palm oil-based diets did not increase in saturated fatty acids content but showed significantly lower polyunsaturated fatty acid (PUFA) concentrations compared to fish fed the CLO diet. The concentrations of individual PUFA in muscle lipids were strongly influenced by dietary PUFA concentrations. Dietary lipids did not markedly affect the structural integrity of erythrocyte membranes but the erythrocytes of tilapia fed the CPO diet were slightly more resistant to osmotic lysis. It was concluded that palm oil products, especially CPO, could be successfully used in the diet of hybrid tilapia based on its availability, cheaper costs and its potential ability to enhance oxidative stability due to its low PUFA content and high natural concentrations of antioxidants. 相似文献
993.
994.
Testosterone (T) administration to maleAnabas testudineus significantly stimulated the activities of cytochrome oxidase, -glycerophosphate dehydrogenase (-GPDH) and Mg2+ adenosine triphosphatase (Mg2+ ATPase) and inhibited lactate dehydrogenase (LDH), cytosolic and mitochondrial malate dehydrogenases (MDH). The activities of succinate dehydrogenase (SDH), glucose-6-phosphate dehydrogenase (G-6-PDH) and catalase were unaffected by testosterone treatment. Administration of estradiol-17 (E2) in female fish, significantly stimulated cytochrome oxidase activity, inhibited Mg2+ ATPase, SDH, catalase and cytosolic and mitochondrial MDH activity, and was without effect on other enzymes studied.The simultaneous injections of actinomycin D or chloramphenicol and T or E2 prevented the hormonal influence on hepatic enzyme activities. The present study demonstrates that inA. testudineus sex steroids influence hepatic oxidative metabolism by a mechanism sensitive to the action of inhibitors of protein synthesis. 相似文献
995.
Changes in lipid class and fatty acid composition during development in pike (Esox lucius L) eggs and larvae 总被引:1,自引:0,他引:1
To establish the changes which occur during embryogenesis and early larval development, eggs, yolk sac larvae and swim-up
larvae of pike were examined for lipid class and fatty acid composition. At a water temperature of 15.5°C, the embryonic phase
was short (6 days) and characterized by a 41.3% decline in the lipid content of eggs, accompanied by large reductions in the
amount of phosphatidylcholine (41.4% decrease), sterol esters and triacylglycerols (respectively a 41.2% decrease and a 58.1%
decrease), but not phosphatidylethanolamine which increased markedly (35.6%). By the time of yolk sac absorption (7 to 11
days after fertilization) the larvae remained inactive and a limited utilization of lipids was observed. Yolk sac phosphatidylcholine
was selectively incorporated into larval bodies while the levels of other lipid classes remained unchanged in the yolk. When
the swim bladder was filled and the swimming stage was reached (11 days to 13 days af), the yolk was completely depleted and
yolk phosphatidylcholine together with yolk triacylglycerols were catabolised. Yolk phosphatidylethanolamine and yolk sterol
esters were partly incorporated into the body lipids. In the subsequent swim-up larval stage (13 to 15 days af), a steady
decrease in lipids was observed (41.6%). Fluctuations in the levels of polyunsaturated fatty acids, monounsaturated fatty
acids or saturated fatty acids examined from eggs or larvae were consistent with changes in lipid classes during pike development.
During yolk sac absorption, pike incorporated yolk PUFA released on hydrolysis of phosphatidylcholine into the larval body.
The results are discussed with reference to water temperature and in relation to the ontogenic and ecological context of pike
development.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
996.
饲料中添加胆碱对黄鳝生长、组织脂肪含量及消化酶活性的影响 总被引:1,自引:0,他引:1
研究了饲料中添用不同含量胆碱对黄鳝生长、饲料利用效率、肌肉和肝脏脂肪含量、肝体指数及消化器官4种消化酶活性的影响。结果表明,饲料中添加的胆碱含量不同,对黄鳝的影响不同,饲料中胆碱添加量在0~2.0%内,随着胆碱添加量的提高,黄鳝的生长速度会加快,饲料系数会逐步降低,肌肉、肝脏的脂肪含量及肝体指数降低,前肠、后肠和肝脏的蛋白酶、胰蛋白酶、淀粉酶和脂肪酶的活性均会相应的提高,而且饲料中的添加量达0.8%~1.0%时,这些变化显著,表明胆碱对黄鳝是不可缺少的,黄鳝饲料中胆碱的适宜添加量为0.8%~1.0%。 相似文献
997.
998.
Archana A. Sharbidre Vimal Metkari Priyanka Patode 《Pesticide biochemistry and physiology》2011,101(2):132-141
Tests of acute toxicity were performed on the most common species of aquarium fish, Poecilia reticulata. Guppies (P. reticulata) were exposed to progressive concentrations of methyl parathion (MP) and chlorpyrifos (CPF); a semi-static method according to guidelines of OECD was used. Tests of acute toxicity were conducted using 10 fish for each separate concentration and for the control group. The results were subjected to probit analysis to determine the 96 h LC50 values. The 96 h LC50 values of MP and CPF to P. reticulata were 8.48 ppm/L (5.98–10.89) and 0.176 ppm/L (0.313–0.224) respectively. In addition, behavioral changes at each concentration were observed for the individual fish. Fish were exposed for 96 h to different sublethal concentrations of MP and CPF (¼ LC50, 1/8 LC50 and 1/10 LC50) and their oxidative stress-induction potential was estimated in brain, liver and gills of fish. MDA content is induced in all tissues but maximum rise was observed in gills (161% and 153% for MP and CPF respectively). With regard to antioxidant defense system (ADS), GSH level decreased in the brain, liver and gills of tissues of MP treated fishes (22%, 6% and 13% respectively) and showed increase in brain and gills CPF treated (23% and 21% respectively). CAT, GST, GR and SOD levels fluctuated in all treatment groups relative to the control. Brain AChE showed dose-dependent inhibition in fish exposed to the higher concentrations reached 45% and 66% for MP and CPF respectively. Collective findings demonstrated that pesticide exposure of fish induced an increase in MDA and fluctuated ADS along with inhibited AChE. These findings may be used as valuable biomarkers for evaluation of water pollution. 相似文献
999.
为明确狭卵链格孢菌Alternaria augustiovoide菌株AAEC05-3产生的毒素细交链孢菌酮酸(tenuazonic acid,TeA)的作用机制,利用离体试验,研究了TeA对稗草叶片细胞膜脂质过氧化的影响。结果显示,低浓度TeA处理对稗草叶片的细胞膜透性和脂质过氧化影响不大;用高浓度TeA处理稗草叶片24 h后,稗草叶片细胞膜透性和脂质过氧化作用显著增强。TeA浓度为100 μmol/L时,稗草叶片相对电导率和丙二醛(MDA)含量分别增加28.21%和63.58%;脂氧合酶(Lox)活性增高61.59%,且不饱和脂肪酸含量显著降低,亚油酸(18∶2)和亚麻酸(18∶3)分别降低19.56%和17.20%,脂肪酸氢过氧化物在叶片中大量积累。表明TeA可以诱导稗草叶片细胞膜的脂质过氧化作用。 相似文献
1000.
活化过硫酸钠氧化土壤对挥发性有机污染物吸附特性的影响 总被引:2,自引:0,他引:2
活化过硫酸钠(Sodium persulfate,SPS)氧化技术是一种新型的土壤修复技术。为了更科学地评价化学氧化处理后土壤的环境风险,本文通过亚铁离子活化过硫酸钠法对有机质(Organic matter,OM)含量存在显著差别的两种土壤进行氧化处理,比较了活化过硫酸钠氧化前后两种土壤样品对3种挥发性有机污染物的吸附特性。结果表明,亚铁活化的SPS能够氧化土壤中腐殖酸和胡敏素类的有机质。对OM含量较高的1号土,SPS氧化对有机质的去除率为71.9%。而对OM含量较低的2号土,SPS氧化对有机质的去除率为49.9%。1号土样对3种挥发性有机物的吸附以分配作用为主,氧化后的1号土样对3种物质的吸附机制不变,但吸附量有所增加;2号土样对3种挥发性有机污染物的吸附有一定的非线性,而氧化后的2号土样对3种物质的吸附线性特征增强。吸附数据用对数形式的Freundlich方程拟合得到分配系数lg Kf值,比较有机碳标化后的分配系数lg Kfoc,氧化后的土壤有机质对3种挥发性有机污染物的吸附特性有所提高。分析表明,SPS氧化了有机质中较多的极性组分(如羧基及羟基等),从而使处理后的土壤中有机质的非极性增强,强化了对非极性化合物的吸附。 相似文献