Enhanced biodegradation of di-n-butyl phthalate by Acinetobacter species strain LMB-5 coated with magnetic nanoparticles

Phthalate acid esters (PAEs) are widely present in a variety of consumer products and they pose a public health concern due to the high mobility and hazards. In this study, we designed an immobilized method to eliminate phthalates by using Fe3O4@NH2 nanoparticles (NPs). The surface-modified NPs showed a good dispersion property, and the particle size was approximately 230 nm. The results showed that Acinetobacter sp. strain LMB-5 could be coated by the prepared magnetic particles allowing easy separation from solution by applying an external magnetic field. The coated cells possessed adaptability to a wide range of pH and high tolerance towards toxic substances. More importantly, when the temperature was elevated to 60 degrees C, the coated cells also exhibited remarkable degradability. There was no change in the main metabolites during the biodegradation between the free cells and immobilized ones through GC/MS analysis to detect the degradation intermediates. These results show that immobilization method using magnetic nanoparticles is a promising way for degradation of phthalates in application. (C) 2016 Elsevier Ltd. All rights reserved.