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海水中多环芳烃的暴露浓度对鲈鱼体内脂质过氧化程度的影响 总被引：2，自引：0，他引：2
本文以鲈鱼为实验材料，以鲈鱼体内的丙二醛含量为指标研究了在水样中16种多环芳烃组分和外加芘为实验试剂的条件下，鲈鱼体内不同器官、组织的脂质过氧化程度的变化．实验结果表明：（1）在鲈鱼鳃、全血中的丙二醛浓度较高，而肝脏的丙二醛浓度较低。（2）水样中多环芳烃及外加芘的暴露能导致鲈鱼肝的丙二醛浓度升高，这表明多环芳烃以及芘的暴露能引起鲈鱼肝内脂质过氧化程度的提高。（3）水体中多环芳烃及外加芘浓度的变化对鲈鱼肝的丙二醛浓度的影响具有可逆性，且鲈鱼肝的丙二醛浓度与水环境的多环芳烃（包括芘）暴露浓度呈良好的正相关关系。这说明：鲈鱼肝的丙二醛浓度可作为指示水环境的多环芳烃污染程度的指标。由于生物体内的丙二醛浓度受多种因素的影响，在使用丙二醛浓度指标来指示海洋环境的多环芳烃污染时。最好与其他指标配合使用，以更准确地指示海洋环境多环芳烃污染。 相似文献
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苯并(a)芘、芘及其混合物暴露对梭鱼肝脏谷胱甘肽硫转移酶活性的影响 总被引：10，自引：0，他引：10
在实验生态条件下,观察苯并(a)芘、芘及其等浓度混合物暴露对梭鱼(Mugil so-iuy)肝脏谷胱甘肽硫转移酶(GST)活性的影响。结果显示,在7d的暴露中,苯并(a)芘、芘对肝脏GST活性的影响主要为诱导效应,芘对GST活性的诱导比苯并(a)芘强。混合物在15d的暴露中未观察到GST活性的诱导,而是在暴露的后期出现GST活性的抑制。实验表明,肝脏GST活性的诱导指示受到PAHs污染胁迫,而GST活性抑制则是受到较长时间或较严重的污染。 相似文献
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苯并（a）芘对大弹涂鱼肝脏超氧化物歧化酶活性的影响 总被引：18，自引：1，他引：18
在实验生态条件下，研究了在苯并（a)芘（BaP)胁迫下大弹涂鱼肝脏超氧化物歧化酶（SOD）活性的变化，结果显示：暴露3d时，不同BaP含量组大弹涂鱼肝脏SOD活性无显著差异（P＞0．05），而暴露7d时，随着B aP含量的升高，0.5mg/dm^3 BaP含量组SOD活性被显著诱导（P＜0．05），为对照组的1．87倍；随着暴露时间的延长，各含量组肝脏SOD的活性均表现出不同程度的下降趋势，其中对照组肝脏SOD活性显著降低，表明SOD活性易受污染以外的因素，如水体容量、铒料、光照等的影响。污染解除后，0.5mg/dm^3含量组SOD活性显著升高，表明大弹涂鱼肝脏仍具有较强的生理调节机能，也可能表明SOD活性的变化相对于环境因子改变的“迟滞性”。以上这些结果表明SOD有可能作为大弹涂鱼受BaP胁迫的生物指标。 相似文献
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海洋环境中微塑料和多环芳烃(PAHs)污染日益严重,以滤食动物菲律宾蛤仔(Ruditapes philippinarum)为研究对象,探讨了聚苯乙烯微塑料和芘单一及联合暴露对菲律宾蛤仔的毒性效应.分别采用两个聚苯乙烯微塑料粒径(0.3μm和6μm,20 μg/L)和两个芘浓度水平(10 μg/L和100μg/L)单独和联合暴露21d,测定其对菲律宾蛤仔生理活动(肥满度和摄食率)、免疫防御、氧化应激等相关生物标志物的影响.研究结果表明,除芘单一暴露组外,其余暴露组菲律宾蛤仔的摄食率与对照组相比都显著降低,但这两种污染物对菲律宾蛤仔的肥满度没有显著影响.微塑料和芘暴露均导致菲律宾蛤仔免疫功能受损,表现为血细胞凋亡率增加和吞噬活性被抑制;其中,在小粒径微塑料和高浓度芘存在的暴露组血细胞凋亡率均显著高于对照组,并且二者联合暴露组血细胞凋亡率最高;除大粒径微塑料暴露组外,各暴露组血细胞吞噬活性均显著低于对照组.菲律宾蛤仔抗氧化酶系统不能及时清除体内产生的自由基,导致机体出现氧化损伤现象,表现为抗氧化酶活性变化和丙二醛(MDA)含量升高.微塑料和芘联合暴露导致鳃组织谷胱甘肽疏基转移酶(GST)活性显著升高,消化腺组织过氧化氡酶(CAT)和超氧化物歧化酶(SOD)活性显著降低.综合生物标志物指数(IBR)结果显示,联合暴露对菲律宾蛤仔造成的胁迫压力高于单一暴露组. 相似文献
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研究了黑鲷(Sparusmacro cephalus)在实验生态条件下暴露于不同浓度苯并(a)芘(benzo(a)pyrene,BaP)后,肝脏乙氧基异吩噁唑酮脱乙基酶(EROD)活性在不同暴露时相的动力学变化情况.EROD活性采用动力学方法测定.实验结果表明,暴露于较低质量浓度BaP(0.5,1.0μg/L)黑鲷肝脏的EROD活性在2 d后极显著高于对照组(P<0.01),2.0μg/L组则在2 h后极显著高于对照组,并且随暴露时间的延长,诱导程度表现出不同的下降趋势,而暴露于高质量浓度组(5.0 μg/L)的肝脏EROD活性极显著性诱导出现在12h.总体上较高质量浓度组(2.0,5.0μg/L)EROD活性出现极显著性诱导的时间比低质量浓度组(0.5,1.0μg/L)早,诱导程度也比低质量浓度组的高.在净化实验中各暴露组肝脏EROD活性均下降,与空白对照组比较均没有显著性差异,说明试验浓度没有超出严重损伤肝脏自身恢复系统的范围,在此浓度范围内污染的鱼通过净化可清除BaP污染. 相似文献
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利用LevelⅢ逸度模型对苯并[a]芘在辽河口湿地大气、水体、土壤、沉积物和植物中的分布进行模拟,通过灵敏度分析确定了模型的关键参数,并对模拟结果进行验证,成功模拟了各相中苯并[a]芘浓度分布,并根据模拟结果计算了各相间的迁移通量。结果表明:大气、水体、土壤、沉积物和植物中苯并[a]芘的浓度分别为7.79×10-11、2.52×10-6、6.32×10-4、1.10×10-3和1.51×10-8 mol/m3,模型计算浓度与同期实测浓度吻合较好,验证了模型的可靠性;土壤和沉积物是苯并[a]芘最主要的储库,占区域总量的94.0%;大气和水的平流输入是该区域苯并[a]芘的主要来源,占总输入量的99.3%,大气和水的平流输出是其损失的主要途径,占总输出量的92.8%;各相间迁移通量以水体向沉积物的迁移通量为最大,依次为沉积物向水体和大气向土壤的迁移。 相似文献
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从红树植物红海榄叶片中分离一株对芘具有较好降解作用的海洋细菌,命名为B11,并对其菌体特征、生长条件及降解效能等进行了系统研究。结果发现该菌株为革兰氏阴性菌,结合其生理生化特征和16S rDNA序列比对,表明此菌株属于交替单胞菌属(Alteromonas sp.)。菌株在芘的起始浓度为100 mg/L,pH为中性或偏碱性条件下,盐度35时对芘的降解作用最强。外加碳源对B11对芘的降解效果都具有一定的抑制作用,其中水杨酸的抑制作用更为显著。综合菌株B11的生长特性和降解效能,初步认为B11菌株较适合用于降解多环芳烃芘,可用于红树植物多环芳烃生态污染的原位修复。 相似文献
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为阐释不同浓度苯并（a）芘[B（a）P]对杂色鲍（Haliotis diversicolor）的毒性效应,以0.02、0.04和0.08 mg/dm^33个质量浓度的B（a）P对杂色鲍进行水体暴露胁迫,7d后检测肌肉、外套膜、鳃、性腺、肾和肝胰腺的超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、谷胱甘肽S-转移酶（GST）和谷胱甘肽过氧化物酶（GPx）活性及还原型谷胱甘肽（GSH）含量.结果显示：0.02 mg/dm^3的B（a）P暴露对杂色鲍抗氧化系统的影响不明显,而0.04、0.08 mg/dm^3的B（a）P则显著抑制了SOD、CAT和GPx酶活性以及GSH含量,同时对GST酶活性具有显著的诱导作用;实验还发现,不同组织抗氧化酶活性对B（a）P胁迫的敏感性响应存在较大差异,其中鳃、肾脏和肝胰腺的敏感性响应明显高于肌肉和外套膜.上述结果表明,苯并（a）芘暴露对杂色鲍抗氧化酶活性的影响具有明显的剂量-效应关系及组织差异性,杂色鲍的鳃、肾脏或者肝胰腺的抗氧化酶响应多环芳香烃胁迫的更敏感,可作为B（a）P污染的生物标志物. 相似文献
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Abstract-The effects on hepatic EROD (7-ethoxyresorufin O-deethylase) in Mugil so-iuy exposedto benzo(a)pyrene (BaP), pyrene and their mixtures of equal concentration were investigated, at con-centrations of 0.1, 1.0, 5.0, 10.0, 50.0 μg/dm~3, in experimental condition. Time-effects and dose-response of the biochemical indexs were observed. The results showed that the hepatic EROD activitieswere induced by the exposure of BaP, pyrene and their mixtures at high concentration. Dose-responseconnections were that the hepatic EROD activities were elevated with increasing concentration of the pol-lutants. The combined effect of BaP and pyrene at 1:1 concentration ratio on hepatic EROD activity wasantagonism. 相似文献
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There is a growing body of evidence to suggest that certain polycyclic aromatic hydrocarbons (PAHs) pose a greater hazard to aquatic organisms than previously demonstrated, due to their potential to cause photo-induced toxicity when exposed to ultraviolet (UV) radiation. The consequences of photo-induced toxicity are reported here for embryo-larval stages of the pacific oyster Crassostrea gigas, following exposure to pyrene and benzo[a]pyrene. During laboratory investigations, significant increases in toxicity were observed in the presence of environmentally attainable levels of UV-radiation, compared with embryos exposed to PAH alone, at levels previously deemed to have little acute biological effect. The phototoxicity of pyrene and benzo[a]pyrene completely inhibited the development to the D-shell larval stage when embryos were simultaneously exposed to 5 microg l(-1) PAH and ultraviolet light (UVB = 6.3 +/- 0.1 microW/cm2 and UVA = 456.2 +/- 55 microW/cm2). A linear relationship was also demonstrated for benzo[a]pyrene phototoxicity with decreasing UV light intensity. 相似文献
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菲与芘在砂基培养的红树植物秋茄中的分布与可视化定位 总被引：1，自引：0，他引：1
本研究采用系列浓度盆栽试验研究多环芳烃（PAHs）菲与芘在红树植物秋茄（Kandelia obova-ta）中的迁移与分布规律,采用加速溶剂萃取（ASE）法和气相色谱-质谱（GC-MS）方法测定秋茄叶片和根中的多环芳烃含量,应用倒置荧光显微镜对秋茄叶片中的多环芳烃进行定位表征.结果表明：秋茄能从培养液中吸收菲和芘,并将根系吸收的菲和芘向叶片运输.秋茄体内菲和芘含量随处理时间（4、8、21 d）呈现先上升后下降的趋势,在培养8 d达到最大值.与4 d和8 d处理相比,在21d试验完成后,秋茄根与叶中的菲和芘含量显著降低,表明在红树植物体内存在明显的PAHs降解或者挥发.秋茄根系中的菲和芘含量随处理浓度提高而增高,与叶片相比,PAHs更多地在根部累积.在叶片中,菲和芘主要储存在叶片的维管束及附近的海绵组织中. 相似文献
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Glycine N-methyltransferase (GNMT) is a mediator in the methionine and folate cycles, and is responsible for the transfer of a methyl group from S-adenosylmethionine (SAM) to glycine forming S-adenosylhomocysteine (SAH) and sarcosine. All the known DNA methyltransferases use SAM as a methyl donor thus, GNMT is critically involved in regulation of DNA methylation. Altered GNMT activities have been associated with liver pathologies including hepatocellular carcinoma. The homotetramer form of GNMT is enzymatically active, but the homodimeric form has been suggested as the 4S PAH-binding protein which may mediate CYP1A expression. To further understand the role of GNMT in benzo(a)pyrene (BaP)-related toxicity, full length Fundulus heteroclitus GNMT cDNA was cloned from adult liver. The open reading frame (ORF) of GNMT is 888 base pairs long and encodes a deduced protein of 295 amino acids which has 74% identity with human GNMT. Expression of GNMT mRNA was determined by quantitative RT-PCR. In unfertilized, 2 days postfertilization (dpf), and 3 dpf embryos GNMT was constitutively higher than in 4, 7, 10 or 14 dpf embryos. Embryos were also exposed to waterborne BaP at 10 and 100 μg L−1, and by 10 dpf the higher BaP dose caused increased expression of GNMT mRNA. These results suggest that PAH exposure may alter expression of an important physiological methylation mediator. Future work will be necessary to determine enzyme level effects of BaP exposure as well. 相似文献
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A micro-extraction technique was used to examine in vivo polycyclic aromatic hydrocarbon (PAH) metabolism in 10 small invertebrate species exposed to sediments amended with 3H-benzo[alpha]pyrene (BaP). Phyla examined included Mollusca (Hydrobia totteni, Ilyanassa obsoleta, Yoldia limatula, and Gemma gemma), Annelida (Nereis succinea, Pectinaria gouldii, Haploscolopolous sp., and Capitella sp. 1) and Arthropoda (Edotea triloba, and Gammarus mucronatus). Organisms were exposed to BaP-labeled sediments, harvested, and parent BaP separated from all polar metabolites by liquid extraction The percent of BaP-derived radio-activity present as polar metabolites ranged from 96% for N. succinea to 7% for P. gouldii. Wide ranges in metabolic capability were also observed between species in the other two phyla examined. Reverse-phase HPLC analysis of extracts of representative species from each phyla indicated that all these organisms form bay region metabolites, with two species forming the 7,8-dihydrodiol (N. succinea and G. mucronatus). In light of the high variability in metabolic capability observed within each phylum, species-specific information on metabolic ability should be obtained before assessing bioaccumulation, critical body burdens, or trophic transfer of PAHs in invertebrates. 相似文献