title: BMAA extraction of cyanobacteria samples: which method to choose?
abstract: β-N-Methylamino-L-alanine (BMAA), a neurotoxin reportedly produced by cyanobacteria, diatoms and dinoflagellates, is proposed to be linked to the development of neurological diseases. BMAA has been found in aquatic and terrestrial ecosystems worldwide, both in its phytoplankton producers and in several invertebrate and vertebrate organisms that bioaccumulate it. LC-MS/MS is the most frequently used analytical technique in BMAA research due to its high selectivity, though consensus is lacking as to the best extraction method to apply. This study accordingly surveys the efficiency of three extraction methods regularly used in BMAA research to extract BMAA from cyanobacteria samples. The results obtained provide insights into possible reasons for the BMAA concentration discrepancies in previous publications. In addition and according to the method validation guidelines for analysing cyanotoxins, the TCA protein precipitation method, followed by AQC derivatization and LC-MS/MS analysis, is now validated for extracting protein-bound (after protein hydrolysis) and free BMAA from cyanobacteria matrix. BMAA biological variability was also tested through the extraction of diatom and cyanobacteria species, revealing a high variance in BMAA levels (0.0080-2.5797 μg g(-1) DW).
authors: Department of Ecology, Environment and Plant Sciences, Stockholm University, 10654, Stockholm, Sweden.
authors: Sandra
authors: S
authors: Lage
authors: Department of Ecology, Environment and Plant Sciences, Stockholm University, 10654, Stockholm, Sweden.
authors: Alfred
authors: A
authors: Burian
authors: Department of Ecology, Environment and Plant Sciences, Stockholm University, 10654, Stockholm, Sweden.
authors: Ulla
authors: U
authors: Rasmussen
authors: IPMA - Instituto Português do Mar e da Atmosfera, 1449 006, Lisbon, Portugal.
authors: Pedro Reis
authors: PR
authors: Costa
authors: Regito AB, 28022, Vittsjö, Sweden.
authors: Heléne
authors: H
authors: Annadotter
authors: Department of Biological and Environmental Sciences, University of Gothenburg, 40530, Gothenburg, Sweden.
authors: Anna
authors: A
authors: Godhe
authors: Department of Ecology, Environment and Plant Sciences, Stockholm University, 10654, Stockholm, Sweden. sara.rydberg@su.se.
authors: Sara
authors: S
authors: Rydberg
mesh_terms: D000599:Amino Acids, Diamino / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D053000:Analytic Sample Preparation Methods / Q000379:methods*; D000458:Cyanobacteria / Q000737:chemistry* / Q000378:metabolism; D000087522:Cyanobacteria Toxins; D009498:Neurotoxins / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D053719:Tandem Mass Spectrometry
chemical_list: D000599:Amino Acids, Diamino; D000087522:Cyanobacteria Toxins; D009498:Neurotoxins; C001824:beta-N-methylamino-L-alanine
keywords: Cyanobacteria; Diatoms; Extraction; Validation; β-N-Methylamino-L-alanine