Light induced aggregation of protein-containing compounds

We examine particle size after sunlight irradiation in three natural seawaters, eight marine microbial exopolymeric substance solutions, and five standard biopolymer solutions. We find that protein-containing dissolved organic matter (DOM) polymers and reactive oxygen species play important roles in aggregate formation during irradiation. The photo-flocculation of DOM provides new insights into polymer assembly, bioavailability of DOM in the global carbon and nitrogen cycles.