Co-immobilization of Chaetoceros calcitrans MZB-1 and culture medium in alginate beads for bioremediation of perfluorooctanoic acid and perfluorooctanesulfonic acid in seawater.

This study investigated the performance of immobilized Chaetoceros calcitrans MZB-1 for the removal of perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) from seawater. The optimal conditions for preparing immobilized alga MZB-1 were as follows: sodium alginate (SA) concentration, 2%; calcium chloride (CaCl2) concentration, 3%; initial algal inoculation density, 5 × 106 cells/mL; and culture medium, 2F. Across all levels of environmental factors (temperature, pH, salinity, and light intensity), the removal efficiencies of PFOA and PFOS by the immobilized alga were consistently 6%-10% higher than those achieved by the free alga. Furthermore, the immobilized alga exhibited high storage stability after 60 d of preservation. Preliminary studies based on microcosm experiments showed that immobilized alga could continuously remove PFOA and PFOS in seawater for more than 60 d, with net removal efficiencies of 48.7% and 50.9%, respectively. In addition, compared with treatments without the immobilized alga, the immobilized alga partially mitigated PFASs-associated declines in microbial richness and diversity. These results highlight the potential of immobilized alga MZB-1 for enhancing the removal of PFOA and PFOS in marine environments.