HR MAS 1H NMR spectroscopy analysis of marine microalgal whole cells

Abstract

To study the use of nuclear magnetic resonance (NMR) spectroscopy as a method of classification, we performed high-resolution magic angle spinning proton (HR MAS 1 H) NMR spectroscopy analysis of whole-cell samples of Dunaliella sp. (Chlorophyceae), Amphidinium carterae (Dinophyceae), Phaeodactylum tricornutum and Thalassiosira pseudonana (Bacillariophyceae). Emphasising the potential use of NMR spectroscopy as a routine analysis of microalgae we chose a straightforward procedure for culturing and harvesting, without extraction or radioactive labelling. We obtained well-resolved HR MAS 1 H NMR spectra from the 4 algae, despite the fact that our samples contained whole cells and some residual sea water. Selected parts of 5 replicate spectra from each microalga were used as input in 2 multivariate pattern-recognition strategies (principal component analysis and fuzzy clustering), both analyses showing clear grouping of the different species. Two spectra from a previous sample run (cultures grown under the same conditions) were also included, and both were correctly classified. We therefore consider HR MAS 1 H NMR spectroscopy to be a potential method of classification for microalgae, with statistical data processing indicating replicability and robustness of the method.

Application of cross‐flow ultrafiltration for isolating exopolymeric substances from a marine diatom (Amphora sp.)

“…Recently, many advanced analytical techniques have been used to characterize polysaccharides, such as gas chromatography-mass spectrometry (GC-MS), Fourier transform infrared spectroscopy (FTIR), high performance liquid chromatography (HPLC), nuclear magnetic resonance (NMR), etc. (Chauton et al 2003;Lim et al 2005;Nordmark et al 2005). Some of these techniques, e.g., NMR, require relatively large (e.g., 30 mg or more) amounts of analytes.…”

Metabolic fingerprinting reveals differences between northern and southern strains of the cryptic diatomChaetoceros socialis

“…In this paper we present the results of metabolite analyses performed on the northern and southern strains of C. socialis from the same experiment described in Degerlund et al (2012) and relate these data to physiology data. A metabolic fingerprinting approach has already been shown to be able to separate phytoplankton species belonging to different genera (Chauton et al, 2003;Barofsky et al, 2009). Here, we demonstrate that metabolic fingerprinting can also be used to distinguish between closely related taxa, such as the 'forms' or pseudocryptic species of C. socialis.…”

“…Only a few metabolomics studies have so far been performed on microalgae grown in different environmental conditions (Bo¨lling & Fiehn, 2005) or on the metabolite profiles of the different growth stages of microalgae (Barofsky et al, 2009(Barofsky et al, , 2010Vidoudez & Pohnert, 2012). Chemotaxonomic studies using metabolomic data on microalgae have been shown to be promising in species discrimination using NMR spectroscopy (Chauton et al, 2003).…”

The use of HRMAS NMR spectroscopy to study the in vivo intra–cellular carbon/nitrogen ratio of Solieria chordalis (Rhodophyta)

“…By using this in vivo NMR technique Chauton et al (2003) classified several microalgal species and Broberg et al (2000), quantified some metabolites in the red macroalga Gracilariopsis lemaneiformis. Furthermore, only a few minutes are required in order to produce well resolved 1 H NMR spectra of intracellular compounds, and this allows for an accurate analysis from inside selected cells.…”