2005年厦门市三起雪卡毒素中毒情况分析

Study of three ciguatera fish poisoning cases in Xiamen city,in 2005

目的 分析引发2005年厦门3起雪卡毒素中毒的原因及引发中毒的鱼种.方法 采集3起中毒案例中剩余的棕点石斑鱼及市场上其他深海鱼共7份,采用小鼠生物法、雪卡毒素免疫膜试剂盒测定雪卡毒素,同时提取中毒鱼肉组织中的mtDNA,采用PCR技术扩增细胞色素6（Cry b）部分序列片段并直接测序,将结果与CenBank数据库比对.结果 引发中毒的鱼肉中雪卡毒素检测呈阳性,小鼠生物实验毒性为0.11小鼠单位（MU）/g,提取的mtDNA扩增出475 bp大小的Cty b基因片段,与棕点石斑鱼（登录号 AY950695）的Cry b基因相似性达99%.其余6份样品均未检出雪卡毒素.结论 这3起中毒事件均是由于食用了含有雪卡毒素的棕点石斑鱼而引发的食物中毒.

Objective To find out the reason of three eiguatem fish poisoning cases in Xiaman in 2005 and identify the fish species.Methods The grouper implicated in food poisoning and seven other coral reef fishes collected from market were tested by mice bioassay and ciguatoxin-test kit.The mtDNA was extracted from toxic grouper meat,and Cty b gene segment was amplified and the PCR products were sequenced.The sequences were compared with those in the GenBank.Results The result turned out to be positive by the ciguatoxin-test kit,while the toxicity of the toxic grouper implicated in food poisoning was 0.11 mouse unit（MU）/g by mice bioassay.A 475 bp segments of Cty b gene was amplified by PCR and the sequence was 99% homologous with Epinephelus fuscoguttatus（GenBank：AY950695）.No ciguatoxin in six grouper species collected from market was detected.Conclusion All three food poisoning cases were caused by consumption of ciguatoxin-carrying groupers.