Molecular model of beta-Methylamino-L-alanine or BMAA. Molecular formula C4 H10 N2 O2, Molar mass 118.13 g/mol. BMAA is a neurotoxin found in the seeds of the cycad (Cycas circinalis), which were used as food and traditional medicine by the Chamorro people of Guam. BMAA is produced by cyanobacteria of the genus Nostoc that live on the cycad plant's roots. Key: Carbon- brown, Hydrogen- yellow, Nitrogen- blue, Oxygen- green.