Microbial degradation of phthalic acid and its esters by aerobic granules in sequencing batch reactor

Phthalates are primarily synthetic compounds have been widely used in industry and consequently became ubiquitous pollutants in natural environment. However, conventional activated sludge process can not effectively treat recalcitrant phthalate wastewater. Therefore, it has been thoroughly realized that bioaugmentation presents significant capability as one of the strategies for enhancement of recalcitrant compound degradation. However, there still exist many factors may affect the efficiency of bioaugmentation in which the selection of suitable bioseeds is undoubtedly an important parameter. During current study, it can be concluded that the strategy of bioaugmentation phthalic acid-degrading aerobic granules is successful in enhancement the degradation of high strength of phthalic acid, di-methyl phthalate (DMP) and di-butyl phthalate (DBP) which is one of the recalcitrant phthalates. The enzyme introduced with phthalic acid aerobic granules can change the DMP degradation rate to be k3 > k2> k1, which makes the phthalate degradation proceeded smoothly. Also, the microbial diversity and immigration analyzed by denaturing gradient gel-electrophoresis (DGGE) show that isolate PA-02 also plays an important role in the enhancement of phthalate degradation.Doctor of Philosophy (CEE