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

OBJECTIVE

To find out the reason of three ciguatera fish poisoning cases in Xiamen 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.