Cyanobacteria used as a dietary item in highland Peru produce the non-protein amino acid BMAA

In the mountains of Peru, globular colonies of Nostoc commune (Nostocales) are collected in the highland lakes by the indigenous people, who call them llullucha. They are consumed locally, traded for maize, or sold, eventually entering the folk markets of Cusco and other neighboring cities. Throughout highland Peru, Nostoc commune is highly salient as a seasonal dietary item, being eaten alone, or in picante-a local stew-and is said to be highly nutritious. Nostoc commune has been known to produce unusual amino acids, including those of the mycosporine group, which possibly function to prevent UV damage [1]. We analyzed 21 different Nostoc commune spherical colonies from 7 different market collections in the Cusco area for the presence of b-N-methylamino-l-alanine (BMAA), a neurotoxic amino acid [2] produced by diverse taxa of cyanobacteria [3], using four different analytical techniques (HPLC-FD, UPLC-UV, UPLC-MS, LC-MS-MS). We found using all four techniques that BMAA was present in the samples purchased in the Peruvian markets at levels ranging from 2–22µg/g. Since BMAA has been putatively linked to neurodegenerative disease, it would be of interest to know if the occurrence of neurodegenerative illness is greater among individuals who consume llullucha in Peru.

Acknowledgements: Marilyn Asay, Farnaz Bakshi, T.J. Buretta, Christopher Webster, Wilson Javier Callanaupa

References: 1. Hill, D.R. et al., (1994) Biol. Chem. 269:7726–7734.

2. Rao, S. D. et al. (2006) Exp. Neurol. 201:244–252.

3. Cox, P.A. et al. (2005) PNAS 102:5074–5078.