Chemical fractionation-enhanced structural characterization of marine dissolved organic matter

Neal Arakawa, Scripps Instititution of Oceanography-UCSD, Marine Chemistry and Geochemistry, La Jolla, CA, United States and Lihini Aluwihare, University of California San Diego, Scripps Institution of Oceanography, La Jolla, CA, United States
Abstract:
Describing the molecular fingerprint of dissolved organic matter (DOM) requires sample processing methods and separation techniques that can adequately minimize its complexity. We have employed acid hydrolysis as a way to make the subcomponents of marine solid phase-extracted (PPL) DOM more accessible to analytical techniques. Using a combination of NMR and chemical derivatization or reduction analyzed by comprehensive (GCxGC) gas chromatography, we observed chemical features strikingly similar to terrestrial DOM. In particular, we observed reduced alicylic hydrocarbons believed to be the backbone of previously identified carboxylic rich alicyclic material (CRAM). Additionally, we found carbohydrates, amino acids and small lipids and acids.