MARINE TOXINS AND VENOMOUS AND POISONOUS MARINE ANIMALS
315
Hessel et al. (1960) found the toxin from L. bohur to be soluble
in ethyl acetate, isopropyl alcohol, methylene chloride, methyl ethyl
ketone and carbon tetrachloride. Further experiments indicated that
the active portion probably did not contain acid or basic groups. He
prepared an acetone extraction of the toxic musculature, concentrated
the residue, extracted with ether, evaporated the ether and extracted
the residue with acetone. The light yellow, mobile oil was then emulsified
into frog Ringer's solution and the material assayed on the frog sciatic
nerve. It was found that the toxin had an inhibitory effect on the action
potential, and that this effect could be correlated with the oral toxicity
test in cats.
Subsequently, Hessel (1961) prepared seven fractions of the toxin
by various methods of fractionation. A partially purified product
was obtained by dissolving the toxin in warm methanol and precipitating the non-toxic contaminants by cooling to -2OOC. The toxin was
recovered from the methanol by evaporation and subsequent fractionation was carried out by silicic acid column chromatography. Four
fractions were collected. These were assayed by feeding experiments
with cats, by intraperitoneal injections of aqueous emulsions into mice,
and by studies on the action potential of excised frog sciatic nerve
preparations. The studies indicated that the toxin could be carried
through the seven extraction-fractionation processes. However, the
last two fractions were the only fractions that showed appreciable
toxicity. From this work Hessel concluded that the toxic component
of ciguatera poison probably contains more than one substance, and
that these substances possess polar characteristics, and that they are
probably not phospholipids.
The most recent discussion of extraction and separation procedures
for obtaining ciguatera toxin from L. bohar is that by Banner et al.
(1963b). The method is outlined in Fig. 9. The 4 kg of dried fish, which
does not include the viscera, is equivalent to approximately 16 kg of
whole fresh fish.
According to Li (1965) the toxic portion of ciguatera poison is an
anticholinesterase which causes death through asphyxiation. Protopam
chloride with atropine was found to be an effective antidote.
(b) Toxicology. When semi-purified preparations of the toxin (Banner
et al., 1960) are injected intravenously into rabbits they produce an
immediate fall in blood pressure with a simultaneous increase in
respiratory rate and depth. As the blood pressure returns toward
normal, respiratory rate decreases and becomes irregular. Temporary
changes are noted in the electrocardiogram during the period of
315
Hessel et al. (1960) found the toxin from L. bohur to be soluble
in ethyl acetate, isopropyl alcohol, methylene chloride, methyl ethyl
ketone and carbon tetrachloride. Further experiments indicated that
the active portion probably did not contain acid or basic groups. He
prepared an acetone extraction of the toxic musculature, concentrated
the residue, extracted with ether, evaporated the ether and extracted
the residue with acetone. The light yellow, mobile oil was then emulsified
into frog Ringer's solution and the material assayed on the frog sciatic
nerve. It was found that the toxin had an inhibitory effect on the action
potential, and that this effect could be correlated with the oral toxicity
test in cats.
Subsequently, Hessel (1961) prepared seven fractions of the toxin
by various methods of fractionation. A partially purified product
was obtained by dissolving the toxin in warm methanol and precipitating the non-toxic contaminants by cooling to -2OOC. The toxin was
recovered from the methanol by evaporation and subsequent fractionation was carried out by silicic acid column chromatography. Four
fractions were collected. These were assayed by feeding experiments
with cats, by intraperitoneal injections of aqueous emulsions into mice,
and by studies on the action potential of excised frog sciatic nerve
preparations. The studies indicated that the toxin could be carried
through the seven extraction-fractionation processes. However, the
last two fractions were the only fractions that showed appreciable
toxicity. From this work Hessel concluded that the toxic component
of ciguatera poison probably contains more than one substance, and
that these substances possess polar characteristics, and that they are
probably not phospholipids.
The most recent discussion of extraction and separation procedures
for obtaining ciguatera toxin from L. bohar is that by Banner et al.
(1963b). The method is outlined in Fig. 9. The 4 kg of dried fish, which
does not include the viscera, is equivalent to approximately 16 kg of
whole fresh fish.
According to Li (1965) the toxic portion of ciguatera poison is an
anticholinesterase which causes death through asphyxiation. Protopam
chloride with atropine was found to be an effective antidote.
(b) Toxicology. When semi-purified preparations of the toxin (Banner
et al., 1960) are injected intravenously into rabbits they produce an
immediate fall in blood pressure with a simultaneous increase in
respiratory rate and depth. As the blood pressure returns toward
normal, respiratory rate decreases and becomes irregular. Temporary
changes are noted in the electrocardiogram during the period of