| Summary: | 碩士 === 國立成功大學 === 環境工程學系 === 107 === BMAA (β-methylamino-L-alanine) and its most common structural isomer DAB (2,4- diaminobutyric acid) produced by cyanobacteria, are non-proteinogenic amino acids that have been associated with neurodegenerative diseases. Protein precipitation method was developed to determine the intracellular BMAA concentration in total, free, soluble and protein-bound BMAA fraction remained in cyanobacterial cells, while solid phase extraction (SPE) method was carried out to determine the extracellular free BMAA fraction remained in the supernatant. This method is based on direct analysis of the underivatized molecule, using an amide column for separation by Hydrophilic Interaction Liquid Chromatography (HILIC) and detection by tandem mass spectrometry (MS/MS) using a deuterium labeled internal standard (d3-BMAA). BMAA extraction was carried out in three cyanobacterial strains which are Microcystis aeruginosa PCC7820, Anabaena circinalis and Cylindrospermopsis raciborskii under different growth phases. Intracellular BMAA was detected in both cyanobacterial laboratory culture and environmental samples under different growth phases in the range concentration of 3.76-16.64 µg/g and 9.66-14.45 µg/g, respectively. While extracellular BMAA was detected in the range concentration of 0.0103-0.0446 µg/L. DAB was confirmed to be present in some of the cyanobacterial samples.
|
|---|
