壬基酚对波纹巴非蛤(Paphia undulata)外套膜毒性效应研究

Toxic effect of nonylphenol( NP) on the mantle of Paphia undulate

实验室条件下获得了壬基酚(Nonylphenol,NP)对波纹巴非蛤(Paphia undulata)的96 h LC50值为0.26 mg/L。同时研究了波纹巴非蛤外套膜中超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性、谷胱甘肽(GSH)含量和丙二醛(MDA)含量在低、中、高(浓度分别为1、10和25μg/L)3个浓度NP曝毒以及清水释放下的胁迫响应。结果表明:胁迫1 d时波纹巴非蛤外套膜SOD活性只有低浓度组被轻度抑制,随后总体呈先诱导后抑制的变化趋势;POD活性在整个胁迫期间只有15 d的低、中浓度组被抑制,其他时间总体呈被诱导状态;GSH含量在胁迫1 d和7 d基本上均低于对照组,而15 d时3个浓度组GSH含量均极显著高于对照组(P<0.01);MDA含量随胁迫时间延长呈明显升高的变化趋势。清水释放后,低浓度组SOD活性、POD活性和GSH含量均恢复正常;中、高浓度组只有GSH含量恢复至对照水平。本研究表明NP对波纹巴非蛤外套膜有明显的氧化损伤,且随着NP浓度升高其受损程度增大,高浓度NP胁迫后外套膜SOD活性、POD活性和MDA含量释放实验结束后未能恢复至对照水平。

A laboratory experiment was carried out to study the 96 h LC50 of nonylphenol（ NP） to Paphia undulate. Acute toxic experiment showed the 96 h LC50 of NP to Paphia undulate was 0. 26 mg / L. The changing tendency of superoxide dismutase（ SOD） activity,peroxidase（ POD） activity,glutathione（ GSH） content and malondialdehyde（ MDA） content which exist in P. undulata＇s mantle were simultaneously observed when P. undulate was exposed to low,middle and high concentration of NP（ 1,10 and 25 μg / L） and after the stress was released. The results show that： after Stress Day one,SOD activity of the mantle of P. undulate was slightly inhibited only at low concentration,then showed a trend of first and then decreased. The activity of POD was only inhibited at the time of Day 15 after exposing to low,medium concentration NP group,but each concentration group were almost induced at the other time.The content of GSH on Day one and Day seven were basically lower than the control group,but on Day 15 the content of GSH was significantly higher than that of control group at three different concentrations（ P〈0. 01）. The content of MDA was increased significantly with the prolonging stress time. After the release with clear water,SOD activity and POD activity,GSH content returned to normal level in the low concentration group（ 1 μg / L）; only the content of GSH had a better restoring in the middle and high concentration groups（ 10,25 μg / L）. This study shows that NP has marked oxidative damage to P. undulate＇s mantle,and the damage increased with the increasing concentration of NP. SOD activity,POD activity of the mantle,MDA content and GSH content basically cannot recover to the control level of high concentration of NP stress released after the experiment.