Biomagnification of cycad neurotoxins in flying foxes

@article{Banack2003BiomagnificationOC,
  title={Biomagnification of cycad neurotoxins in flying foxes},
  author={Sandra Anne Banack and Paul Alan Cox},
  journal={Neurology},
  year={2003},
  volume={61},
  pages={387 - 389}
}
β-Methylamino-l-alanine (BMAA) occurs in higher levels in museum specimens of the Guamanian flying fox than in the cycad seeds the flying foxes feed on, confirming the hypothesis that cycad neurotoxins are biomagnified within the Guam ecosystem. Consumption of a single flying fox may have resulted in an equivalent BMAA dose obtained from eating 174 to 1,014 kg of processed cycad flour. Traditional feasting on flying foxes may be related to the prevalence of neuropathologic disease in Guam. 
Previous studies underestimate BMAA concentrations in cycad flour
  • Ran Cheng, S. Banack
  • Biology, Medicine
    Amyotrophic lateral sclerosis : official publication of the World Federation of Neurology Research Group on Motor Neuron Diseases
  • 2009
TLDR
Data support a link between ALS/PDC and exposure to BMAA and detected significant levels of protein-associated BMAA in washed cycad flour.
Biomagnification of cyanobacterial neurotoxins and neurodegenerative disease among the Chamorro people of Guam
  • P. Cox, S. Banack, S. Murch
  • Biology
    Proceedings of the National Academy of Sciences of the United States of America
  • 2003
TLDR
The biomagnification of BMAA through the Guam ecosystem fits a classic triangle of increasing concentrations of toxic compounds up the food chain, which may explain why the incidence of ALS-PDC among the Chamorro was 50-100 times the occurrence of amyotrophic lateral sclerosis elsewhere.
Distribution of the neurotoxic nonprotein amino acid BMAA in Cycas micronesica
TLDR
Cycad neurotoxins are concentrated in cycad reproductive organs, with the highest concentrations being found in the immature staminate sporangium and the outmost layer of the sarcotesta, consistent with the putative evolutionary role of BMAA as an antiherbivory compound, as well as the biomagnification of the compound in flying foxes that ingest the seed sarcOTesta.
Cyanobacterial Neurotoxin β-N-Methylamino-L-alanine (BMAA) in Shark Fins
TLDR
Consuming shark fins may increase the risk for human exposure to the cyanobacterial neurotoxin BMAA, which has been linked to neurodegenerative diseases and may have important relevance to human health.
The fate of the cyanobacterial toxin β-N-methylamino-L-alanine in freshwater mussels.
Production of the Neurotoxin BMAA by a Marine Cyanobacterium
Diverse species of cyanobacteria have recently been discovered to produce the neurotoxic non-protein amino acid β-methylamino-L-alanine (BMAA). In Guam, BMAA has been studied as a possible
Diatoms: A Novel Source for the Neurotoxin BMAA in Aquatic Environments
TLDR
It is demonstrated that diatoms – eukaryotic organisms – also produce BMAA, and the use of filter and suspension feeders as livestock fodder dramatically increases the risk of human exposure to BMAA-contaminated food.
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