| Autor: |
Alves MR; Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California 92093, USA. vhgrassian@ucsd.edu., Coward EK; Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California 92093, USA. vhgrassian@ucsd.edu., Gonzales D; Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California 92093, USA. vhgrassian@ucsd.edu., Sauer JS; Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California 92093, USA. vhgrassian@ucsd.edu., Mayer KJ; Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California 92093, USA. vhgrassian@ucsd.edu.; Department of Chemistry, Colorado State University, Fort Collins, Colorado, 80523, USA., Prather KA; Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California 92093, USA. vhgrassian@ucsd.edu.; Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093, USA., Grassian VH; Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California 92093, USA. vhgrassian@ucsd.edu. |
| Abstrakt: |
Marine chromophoric dissolved organic matter (m-CDOM) mediates many vital photochemical processes at the ocean's surface. Isolating m-CDOM within the chemical complexity of marine dissolved organic matter has remained an analytical challenge. The SeaSCAPE campaign, a large-scale mesocosm experiment, provided a unique opportunity to probe the in situ production of m-CDOM across phytoplankton and microbial blooms. Results from mass spectrometry coupled with UV-VIS spectroscopy reveal production of a chemodiverse set of compounds well-correlated with increases in absorbance after a bacterial bloom, indicative of autochthonous m-CDOM production. Notably, many of the absorbing compounds were found to be enriched in nitrogen, which may be essential to chromophore function. From these results, quinoids, porphyrins, flavones, and amide-like compounds were identified via structural analysis and may serve as important photosensitizers in the marine boundary layer. Overall, this study demonstrates a step forward in identifying and characterizing m-CDOM using temporal mesocosm data and integrated UV-VIS spectroscopy and mass spectrometry analyses. |
