Biodegradation of tetrachlorobisphenol-A in river sediment and the microbial community changes

Abstract

This study investigated the aerobic degradation of tetrachlorobisphenol-A (TCBPA) in sediment samples collected at three sites along Erren River in southern Taiwan. TCBPA biodegradation rate constants (k ₁) and half-lives (t_1/2) ranged from 0.03 to 0.06 day⁻¹ and 11.6 to 23.1 days, respectively. The biodegradation of TCBPA was enhanced by the addition of cellulose, yeast extract, sodium chloride, brij 30, brij 35, surfactin, and rhamnolipid. Of the micro-organism strains isolated from the sediment, we found that strains L1 and L5 (identified as Bacillus megaterium and Pseudomonas putida) expressed the best biodegrading ability. The inoculation of sediment with the TCBPA-degrading bacteria could enhance the efficiency of degradation.

Keywords:

• Biodegradation
• Tetrachlorobisphenol-A
• sediments
• Taiwan

Acknowledgments

This Research was supported by the National Science Council, Republic of China, Grant Number 97-2627-B-031-001. The authors gratefully acknowledge Dr. Jo-Shu Chang at the National Cheng Kung university for his generosity in providing surfactin and rhamnolipid during this study.