Abstract
The non-protein amino acid, β-N-methyl-amino-L-alanine (L-BMAA) from Cycas circinalis seeds, has been implicated as a causative agent of amyotrophic lateral sclerosis
- Parkinsonism dementia complex (ALS-PDC), a disease known from Guam and other areas
in the western Pacific. We analyzed C. circinalis seeds for additional free non-protein amino acids by a recently developed GC-MS method.
The samples were prepared by water extraction of seed flour. The amino acids present
in the extract were derivatized by N(O,S)-isobutyloxycarbonylation of the amine functional groups and then tert-butyldimethylsilylation of the carboxyl functional groups. Peaks for a total of seventeen
derivatives of non-protein amino acids were detected by GC-MS. In addition to L-BMAA, four other non-protein amino acids were identified as β-alanine, γ-aminobutyric
acid, pyroglutamic acid, and α-aminoadipic acid.
Key words
Non-protein amino acids -
Cycas circinalis L. - Cycadaceae - amyotrophic lateral sclerosis-Perkinsonism dementia complex -
N(O,S)-isobutyloxycarbonylation -
tert-butyldimethylsilylation - gas chromatography-mass spectrometry
