Simultaneous removal of calcium, phosphorus, and bisphenol A from industrial wastewater by Stutzerimonas sp. ZW5 via microbially induced calcium precipitation (MICP): Kinetics, mechanism, and stress response

The biological treatment of complex industrial wastewater has always been a research hotspot. In this experiment, a salt-tolerant strain Stutzerimonas sp. ZW5 with aerobic denitrification and biomineralization ability was screened, and the optimum conditions of ZW5 were explored by kinetics. The removal efficiencies of nitrate (NO3--N), bisphenol A (BPA), phosphorus (PO43--P), and calcium (Ca2+) were 94.47%, 100%, 98.87%, and 83.04%, respectively. The removal mechanism of BPA was the adsorption of microbial induced calcium precipitation (MICP) and extracellular polymeric substances (EPS). Moreover, BPA could weaken the electron transfer ability and growth metabolism of microorganisms and affect the structure of biominerals. At the same time, the stress response of microorganisms would increase the secretion of EPS to promote the process of biomineralization. Through nitrogen balance experiments, it was found that the addition of BPA would lead to a decrease in the proportion of gaseous nitrogen. This experiment offers novel perspectives on the treatment of industrial effluents and microbial stress response. Nitrate and PO43--P in industrial wastewater led to eutrophication of water bodies, and BPA has a negative effect on the endocrine of aquatic organisms. In this experiment, a salt-tolerant strain ZW5 capable of efficient aerobic denitrification and biomineralization was screened. The strain ZW5 produced alkalinity in denitrification to promote the MICP, and BPA was adsorbed by hydrogen bonding and pore interaction through MICP and EPS. It was further studied that BPA would cause strain ZW5 to secrete more EPS and improve the MCIP. This experiment offers new insights into industrial wastewater treatment and the stress response of microorganisms.