Domoic acid

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Domoic acid
IUPAC name (2S,3S,4S)-4-[(2Z,4E)-6-carboxyhepta-2,4-dien-2-yl]-3-(carboxymethyl)pyrrolidine-2-carboxylic acid
Identifiers
CAS number 14277-97-5
PubChem 6426712
SMILES CC(\C=C\C=C(\C)/[C@H]1CN[C@@H]([C@H]1CC(=O)O)C(=O)O)C(=O)O
Properties
Molecular formula C15H21NO6
Molar mass 311.33 g/mol
Appearance White powder
Hazards
R-phrases R20 R21 R22
S-phrases S36 S37
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

Domoic acid, which causes amnesic shellfish poisoning (ASP), is an amino acid phycotoxin (algal toxin) found associated with certain algal blooms.[1]

Contents

  • 1 Occurrence
  • 2 Chemistry
  • 3 Toxicology
  • 4 References
  • 5 External links

[edit] Occurrence

In 1958, domoic acid was originally isolated from the red alga called "doumoi" or "hanayanagi" (Chondria armata[2]) in Japan. "Doumoi" is used as an anthelmintic in Tokunoshima, Kagoshima. Domoic acid is also produced by diatoms of the genus Pseudo-nitzschia.[3][4] Domoic acid is commercially available.

[edit] Chemistry

[edit] Toxicology

The chemical can bioaccumulate in marine organisms that feed on the phytoplankton, such as shellfish, anchovies, and sardines. The toxin does not bioaccumulate in the classic sense because it is quickly excreted by fish and shellfish that ingest it. It only accumulates in high numbers in these plankton feeders when the diatom itself is high in number in the surrounding waters. Bioaccumulation or biomagnification typically occurs in lipid-rich tissues, which accumulate toxins over time. In classic bioaccumulation, the older and larger an organism is, the longer it has to accumulate the toxins in its fats, and therefore, the higher the concentration of toxin. In mammals, including humans, domoic acid acts as a neurotoxin, causing short-term memory loss, brain damage, and death in severe cases in Atlantic Canada. Algal bloom are associated with the phenomenon of ASP. Considerable recent research has been carried out by the Marine Mammal Center and other scientific centers on the association of red tides to domoic acid and to resulting neurological damage in marine mammals of the Pacific Ocean. In marine mammals, domoic acid typically causes seizures and tremors.

In the brain, domoic acid especially damages the hippocampus and amygdaloid nucleus. It damages the neurons by activating AMPA and kainate receptors, causing an influx of calcium. Although calcium flowing into cells is a normal event, the uncontrolled increase of calcium causes the cell to degenerate. Because the hippocampus may be severely damaged, long-term memory loss occurs.