Cometabolic biodegradation system employed subculturing photosynthetic bacteria: A new degradation pathway of 4-chlorophenol in hypersaline wastewater.

Schematic diagram of how PSB biodegrade 4-CP with the synergistic effect of varied microorganisms such as the phyla of Proteobacteria , Firmicutes and Bacteroidetes. [Display omitted] • Photosynthetic bacteria (PSB) have a good patience of salinity. • PSB subculturing in absence of NaCl can save 50% inoculation time. • PSB cometabolic system with exogeneous carbon sources for 4-CP degradation. • A new 4-CP degradation way in PSB system is proposed. 4-chlorophenol (4-CP) as a toxic persistent pollutant is quite difficult treatment by using traditional biological processes. Herein, photosynthetic bacteria (PSB) driven cometabolic biodegradation system associated with exogeneous carbon sources (e.g. , sodium acetate) has been demonstrated as an effective microbial technique. The biodegradation rate (r i) can be at 0.041 d−1 with degradation efficiency of 93% in 3094 lx. Through the study of subculturing PSB in absence of NaCl, it was found that 50% inoculation time can be saved but keeping a similar 4-CP biodegradation efficiency in scale-up salinity system. A new plausible biodegradation pathway for 4-CP in 4th G PSB cometabolic system is proposed based on the detected cyclohexanone generation followed by ring opening. It is probably ascribed to the increasement of Firmicutes and Bacteroidetes at phyla level classified based on microbial community. This study contributes to a new insight into cometabolic technology for chlorophenol treatment in industrial hypersaline wastewater. [ABSTRACT FROM AUTHOR]