Puffer Fish Gut Microbiota Studies Revealed Unique Bacterial Co-Occurrence Patterns and New Insights on Tetrodotoxin Producers.

Tetrodotoxin (TTX) is a potent neurotoxin isolated mainly from toxic puffer fish. To date, the TTX biosynthetic mechanism inside its hosts remains unresolved. Here, we hypothesize the TTX synthesis relies on the host gut microbiota, including the neglected non-culturable bacteria.

Rapid screening of tetrodotoxin in urine and plasma of patients with puffer fish poisoning by HPLC with creatinine correction.

A rapid and simple detection method for tetrodotoxin (TTX) in urine and plasma of patients with puffer fish poisoning was developed using commercially pre-packed solid-phase extraction (SPE) cartridges (C18 and weak cation exchange columns) and subsequent analyses by HPLC with UV detection. The detection limit of the standard TTX, TTX-spiked urine and plasma samples were all 10 ng/ml and the average TTX recovery in urine and plasma samples after SPE were 90.3 +/- 4.

Distribution of tetrodotoxin in pufferfish collected from coastal waters of Sihanouk Ville, Cambodia.

In Cambodia, fatal food poisonings associated with the consumption of pufferfish have occurred for decades, but the causative species or toxins have never been documented. Herein, we investigated the toxicity of three pufferfish species of the genus Lagocephalus collected from the coastal waters of Sihanouk Ville, one of the main regions where poisonings have occurred. L.

Occurrence of paralytic shellfish toxins in Cambodian Mekong pufferfish Tetraodon turgidus: selective toxin accumulation in the skin.

The toxicity of two species of wild Cambodian freshwater pufferfish of the genus Tetraodon, T. turgidus and Tetraodon sp., was investigated.

Toxicity assessment for the horseshoe crab Carcinoscorpius rotundicauda collected from Cambodia.

In this study, we assessed the toxicity of the horseshoe crab Carcinoscorpius rotundicauda collected from Cambodia within two successive months during rainy (April-May) and dry (December-January) seasons, respectively. Toxicity assessments of the collected specimens by standard mouse bioassay showed marked individual variation, and their toxin profiles by liquid chromatography/mass spectrometry (LC/MS) revealed tetrodotoxin (TTX) was the main toxin while no paralytic shellfish toxins (PSTs) were detected. All specimens were toxic and the highest toxicity values were 315, 113, 60, 47, 44 and 38 mouse units (MU)/g in the tissues of hepatic caecum, egg, viscera, muscle, intestine and testis, respectively.

Two novel species of tetrodotoxin-producing bacteria isolated from toxic marine puffer fishes.

Out of eight dominant discrete bacterial colonies isolated and purified from the toxic marine puffer fishes collected in Hong Kong waters, two novel species of non-sporing, non-acid-fast and chemoorganotrophic bacteria capable of producing tetrodotoxin (TTX, a potent non-protein neurotoxin), as well as one previously reported and confirmed TTX-producing bacterium. They were identified as Microbacterium arabinogalactanolyticum, Serratia marcescens and Vibrio alginolyticus, respectively, all of which are widely distributed in soils, sewage or marine environments. Each bacterial isolate (500 ml broth medium cultured in darkness without aeration for 10 days at 25 degrees C) could produce an amount of toxicity, after extraction and purification, ranging from 78.

The annual toxicological profiles of two common puffer fish, Takifugu niphobles (Jordan and Snyder) and Takifugu alboplumbeus (Richardson), collected along Hong Kong coastal waters.

The toxicological profiles of two local common puffer fish, Takifugu niphobles (Jordan and Snyder) and Takifugu alboplumbeus (Richardson), collected in Hong Kong waters were investigated continuously for 14 months (June 1997-August 1998). Their annual spawning seasons (as evident by the enlargement of gonads and presence of eggs in the ovary) were found to be from October to February (four consecutive months) and December to February (two consecutive months), respectively. The toxicities of their internal organs were determined by standard mouse bioassay and expressed in terms of mouse units (MU).