Characterization of oxaliplatin removal by multispecies bacterial populations in moving bed biofilm and suspended-biomass reactors.

Abstract

This work aimed to characterize the oxaliplatin removal potential of multispecies microbial populations using the suspended-biomass (SB) and moving bed biofilm (MBB) reactors. Bacterial strains were isolated from pharmaceutical wastewater, their oxaliplatin degrading potential was screened and oxaliplatin removal efficacy in multispecies bacterial populations was investigated using HPLC. Five bacterial strains able to degrade oxaliplatin with an oxaliplatin removal efficacy of 21%-52% were isolated. The synthetic consortium including Xenorhabdus spp., Pantoea agglomerans and Bacillus licheniformis showed the highest potential with an oxaliplatin removal efficacy of 88.6% and 94.0% using the SB and MBB reactors, respectively. Also, the consortium reduced the chemical oxygen demand (COD) by 91.6 and 33% in MBB and SB reactors, respectively. A kinetic study showed a faster oxaliplatin removal in MBB (0.134 kg-1 ) than in the SB reactor (0.101 kg-1 ). Based on the GS/MS analysis, the overall biochemical pathway of oxaliplatin degradation was hypothesized to be initiated through the oxygenation of diamino-dicyclohexan-platinium complex and the cleavage of the aromatic ring. Microbial removal of oxaliplatin using MBB and SB reactors seems to be an efficient and promising approach for oxaliplatin removal in pharmaceutical and hospital wastewater treatment plants. Employing bacterial populations using the MBB reactor is a promising way to treat pharmaceutical wastewater to reduce the discharge of anticancer drugs into the environment.