Unraveling Microplastic-Biofilm\nNexus in Aquaculture:\nDiversity and Functionality of Microbial Communities and Their Effect\non Plastic Traits

Microplastics (MPs) serve as unconventional platforms\nfor microorganisms\nand vectors for pollutants and pathogens in aquatic ecosystems. This\nstudy explored the dynamics of microbial colonization and biofilm\nformation on MPs, a key factor in their ecological impact, using five\ncommon MP typespoly(ethylene terephthalate) (PET), poly(vinyl\nchloride) (PVC), polyethylene (PE), polylactic acid (PLA), and polypropylene\n(PP)incubated in an aquaculture pond for 128 days. The biofilm\nbiomass increased by 173–617% compared with original samples,\nespecially PP- and PE-MPs (OD 595 nm = 0.30 and 0.28, respectively).\nDriven by the inherent properties of MPs, biofilm biomass and microbial\ncommunity structure differed significantly across the MP types, leading\nto varied changes in hydrophobicity and surface morphology. Differences\nin physicochemical properties cause each MP type to selectively enrich\nspecific microbes, profoundly influencing biofilm formation and MP\ndegradation potential. Notably, PP- and PE-MPs supported rich, mature\nbiofilms conducive to carbon cycling and biofilm development, while\nPET-MPs attracted more abundant plastic degraders, like <i>Pseudomonas</i>. The study also highlighted the enrichment of pathogens on MPs,\nindicating potential environmental and human health risk. These findings\nilluminate the complex interactions between MP characteristics and\nbiofilm dynamics, enhancing understanding of MPs’ environmental\nbehaviors and fates in aquatic settings.