太湖微囊藻毒素在罗非鱼体内的累积及生物降解的初步研究

为了解蓝藻水华期间微囊藻毒素在罗非鱼体内的分布及累积传递过程，2008年6月至8月采集了高密度蓝藻池塘及太湖网箱内的鱼样及水样，用ELISA法对鱼样和水样进行微囊藻毒素MC-LR含量的检测。结果表明：池塘水体微囊藻毒素MC-LR含量变化范围在0.123～0.514ug/L间，MC-LR含量随着藻密度的下降而降低，对照组水体MC-LR浓度显著高于实验组MC-LR含量。池塘鱼体肌肉组织微囊藻毒素MC-LR累积含量在1.194～3.615ng/g间，肝脏组织微囊藻毒素MC-LR累积含量显著高于肌肉组织。将池塘与网箱罗非鱼转至无微囊藻水体中暂养，跟踪检测MC-LR含量变化，池塘和网箱鱼体肌肉组织微囊藻毒素MC-LR含量均低于人体每日可耐受摄入量，而肝脏组织藻毒素MC-LR含量则分别需要经过10～20天自然生物降解后降低至安全摄入量之下。并讨论了微囊藻毒素在鱼体内的组织分布与食物链中的累积传递。

The preliminary studies on the accumulation and depuration of microcystins, a cyanobacterial toxin, in Tilapia fish

In order to understand the accumulation and distribution of microcytins (MCs) in Tilapia fish during a cyanbobaeterial bloom from June 2008 to August 2008.The MCs contents of water sample and fish sample in the Pond and Cage were determined by enzyme-linked immunosorbent assay (ELISA). The concentration was expressed as microcystin-LR equivalent. The result demonstrated the MC-LR concentration of water in the pond, positively correlated with the density of cyanobacteria, was from 0.123 to 0.514 ug/L. and the MC-LR concentration of the control was higher than the ones of the experiment. The concentration of MC-LR in muscle tissue is between 1.194 and 3.615ng/g. Comparing the MC-LR concentration of the muscle, the higher MC-LR accumulation in the liver occurred in the ponds. Then the Tilapia fishes in the pond and the cage were transferred to new environment without the microcytins of cyanbobaeterial bloom. The microcystins contents of the liver and muscle samples were detected by ELISA. The concentration of MC-LR in muscle tissue was presented bellow the recommended tolerable daily intake of MC-LR by humans. But the concentration of MC-LR in liver tissue needed 10 to 20 days biodegrading to get to the safely acceptable daily intake for MC-LR. The food chain accumulation and organ distribution of microcystins in Tilapia fish were here in discussion.