Hydrogel immobilized bacteria@metal-organic-frameworks composite augmented bisphenol A removal from activated sludge...

Improving degradation efficiency of activated sludge towards bisphenol A (BPA) is related to water safety. A hydrogel immobilized bacteria@metal-organic-frameworks (im-SQ-2@MOFs) was synthesized previously, which was a composite formed by metal organic frameworks adhering to BPA degrading bacteria. Accordingly, this study added im-SQ-2@MOFs as enhancer to augment the BPA degradation ability of activated sludge. Results indicated that after the addition of im-SQ-2@MOFs, the augmented activated sludge system maintained 90 % BPA degradation rate for 10 mg/L BPA. Meanwhile, the system also presented 80-97 % degradation effect for other phenolic pollutants. Augmentation mechanism was revealed through multi-omics analysis. Firstly, im-SQ-2@MOFs enriched the degradation functional microorganisms in activated sludge, and microbial communication was further prompted. Besides, organic compounds degrading enzymes were upregulated to intensify BPA hydrolysis. Furthermore, electron transfer during BPA degradation was accelerated. Results provide new perspective on the development of bio-augmented materials to improve the efficiency of sewage treatment plants. TAKE HOME MESSAGE.