Freezing Technology

8.3.1 Tetradotoxin

This toxin occurs in different animal species such as pufferfish (Tetraodontidae),a goby, Atelopid frogs Taricha salamanders, octopus and two Japanese shellfishes.  This toxin is mainly found in the liver, ovaries and intestines in various species of pufferfish.  The muscle tissue of the fish is normally free of toxin but there are exceptions.  The occurrence is mainly from ovaries and liver.  In octopus, the toxin is present in the posterior salivary venom glands and will be  used for paralyzing the prey. The toxin was isolated as maculotoxin, chemically similar to tetradotoxin but distinct.

          The poisoning leads to neurological symptoms 10-45 minutes after ingestion.  It acts by preventing nerve conduction by an internally specific and reversible blockage of the inward movement of sodium ions through the cell membrane of an activated neuron.  Symptoms are tingling sensation in face and extremities, paralysis of respiratory system and cardiovascular collapse.  In fatal cases, death takes place within 6 hours.

Tetrodatoxin(TTX) distribution

1. Fish: pufferfish, Fugu(Tetraodontidae) , Goby (Gobius criniger)

2.Amphibians: Newts, Taricha (Salamandridae) frogs, Atelopus varius,

   Atelopus  chiriquiensis (Atelopidae)

3. Octopus, Haplaochlae maculosa (Octopoda)

4.Shellfish(Gastropoda) Ivory shell, Babylonia japonica; trumpet shell,

   Charonia  sauliae

5.Star fish , Astropeeton polyacanthus (Echinodermata)