摘要:
Di-n-butyl phthalate (DBP), a member of the phthalate acid ester (PAE) family, is thought to have an endocrine disrupting effect on vertebrates and humans and has been identified as priority controlled hazardous substance in the United States and China. In order to evaluate the effect of DPB, we examined liver and gill levels of superoxide dismutase (SOD) and malondialdehyde (MDA), and brain levels of acetylcholinesterase (AChE) in the crimson snapper (Lutjanus erythropterus). Groups offish were exposed to 0,0.125, 0.5, or 2.0 mg/LDBP for 0, 6, 12, 24, 48, or 96 h. The 24, 48 and 96h LC50 values were 7.13, 7.02, and 6.75 mg/L, respectively. The safe concentration (SC) of DBP was 2.04 mg·L-1. Gill superoxide dismutase (SOD) activity increased significantly as the concentration of DBP increased. In contrast, there was no clear pattern of induction or inhibition for liver SOD activity, though levels in the groups exposed to 0.5 and 2.0 mg/L were significantly different from the control (P0.05). Brain levels of acetylcholinesterase (AChE) were 32.07%, 62.07%, and 61.60% higher in fish exposed to 0.125, 0.5 or 2.0 mg/L, respectively, after 48 h. However, AChE activity was lower in the treatment groups than in the control group after 96 h exposure (28.87%, 20.12%, and 21.14% lower, respectively). Our results suggest that the effects of DBP on enzyme activity is related to the time of exposure. It could be concluded that DBP causes oxidative stress and neurotoxicity in aquatic organisms. Thus, attention should be given to the potential ecological risk posed by this contaminant.%为了探讨邻苯二甲酸二丁酯(DBP)对红鳍笛鲷(Lutjanus erythropterus)幼鱼的胁迫效应,于DBP暴露后0、6、12、24、48和96 h时检测红鳍笛鲷鳃、肝和脑组织中超氧化物歧化酶(SOD)、丙二醛(MDA)和乙酰胆碱酯酶(AChE)活性.结果表明,DBP对红鳍笛鲷的24 h、48 h和96 h LC50分别为7.10 mg/L、6.98 mg/L和6.66 mg/L,安全质量浓度为2.04 mg/L.随着浓度增加,鳃组织中的SOD酶活性表现为先升高后下降,具有明显的时间效应;肝组织中的SOD酶活性在0.5 mg/L和2.0 mg/L浓度组交替表现为升高和降低,与对照组比较有显著性差异(P<0.05);而0.125 mg/L浓度组肝SOD没有明显变化.鳃组织中MDA含量在DBP暴露6h后显著性增加(P<0.05),之后随时间延长而下降;DBP暴露6h和12h后,0.5 mg/L和2.0 mg/L浓度组肝组织中的MDA含量都显著升高(P<0.05),之后随时间延长MDA含量下降并趋于稳定.与对照组比较,DBP暴露48 h后,红鳍笛鲷脑组织中AChE酶活性显著升高(P<0.01),96 h后又显著下降(P<0.01).SOD、MDA和AChE酶活性变化与DBP暴露时间有关,但与DBP浓度关系不明显.研究结果表明DBP对水生生物存在氧化胁迫和神经毒性.