One of the promised as antifouling activity may be the puffer
fishes crude extracts. Puffer fish are a part of a group called
tetrodotoxic fishes. The ancient Chinese and Japanese were
aware of the toxin contained in puffer fish and used the
non-poisonous parts of the fish as a general health tonic.
Japanese researchers tested the crude puffer fish extract to
treat migraines and menstrual cramps. It is mainly found in
the ovaries, liver, and intestines of various species of puffer
fish, lesser amounts were found in the skin (Kao, 1966 and
Blankenship, 1976). The tetrodotoxin compound has been
obtained from an extract of puffer fish viscera in the form of
colorless crystal that are slightly soluble in water. The toxin
is unstable at pH levels above 8.5 and below 3 (Schantz,
1973 and Scheuer, 1977).