Determination of BMAA in Three Cyanobacterial Strains Under Different Growth Phases

Abstract

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 ?g/g and 9 66-14 45 ?g/g respectively While extracellular BMAA was detected in the range concentration of 0 0103-0 0446 ?g/L DAB was confirmed to be present in some of the cyanobacterial samples

Date of Award	2019
Original language	English
Supervisor	Tsair-Fuh Lin (Supervisor)