Abstract: The efficacy of active and thermally inactivated Lactobacillus rhamnosus in reducing the toxicity of tetrodotoxin (TTX) in the liver of wild puffer fish was evaluated by enzyme-linked immunosorbent assay (ELISA), chromatographic strip test and mouse bioassay. Changes in the contents of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the liver after incubation with this strain were analyzed by gas chromatography-mass spectrometry (GC-MS). The competitive ELISA results showed that thermally inactivated and active Lactobacillus rhamnosus reduced TTX by 82.16% and 70.05%, indicating that better efficacy could be obtained after heat inactivation. In addition, TTX in the liver of wild puffer fish was reduced by 93.27% after 7 days of fermentation by Lactobacillus rhamnosus, and the contents of EPA and DHA in the liver were decreased by 11.93% and 22.50%, respectively. In summary, Lactobacillus rhamnosus can reduce TTX in the liver of puffer fish, and better effect can be obtained after fermentation with Lactobacillus rhamnosus. This study provides a basis for the toxicity reduction of puffer visceral tissues.

Key words: tetrodotoxin, toxicity, Lactobacillus rhamnosus, fermentation, reduction