Two liquid phase partitioning bioreactor system for toxicant free water production from phthalates contaminated aqueous medium

Abstract

Biodegradation of DMP (dimethyl phthalate) and DEP (diethyl phthalate) is a global environmental concern due to their endocrine disrupting nature. In the present study, biodegradation of DEP as the single substrate and a mixture of DMP and DEP as dual substrates were examined in a two-phase partitioning bioreactor (TPPB) using Cellulosimicrobium funkei. The TPPB system was run under batch and fed-batch modes of operation at different initial concentrations of DEP and mixture of DMP and DEP. Under the batch mode of operation, 93% degradation was achieved by C. funkei within 60 h with 38.75 mgL−1h−1 degradation rate. In the fed-batch system, complete degradation was observed up to 3500 mg/L total initial concentration of the phthalates (1500 mg/L DEP and 2000 mg/L DMP) within 24h. Phytotoxicity assessment of the treated water by seed germination and brine shrimp lethality assays revealed a germination index value of 86.17 and 13.33% brine shrimp mortality. Overall, this study revealed a very good potential of the TPPB system for detoxification of endocrine disrupting chemicals in the environment.