Characterization of 1,4-dioxane biodegradation by a microbial community

Abstract

In this study, a microbial community of bacteria was investigated for 1,4-dioxane(1,4-D) biodegradation. The enriched culture was investigated for 1,4-dioxane mineralization, co-metabolism of 1,4-dioxane and extra carbon sources, and characterized 1,4-dioxane biodegradation kinetics. The mineralization test indicates that the enriched culture was able to degrade 1,4-dioxane as the sole carbon and energy source. Interestingly, the distribution of 1,4-dioxane into the final biodegrading products were 36.9% into biomass, 58.3% completely mineralized to CO2, and about 4% escaped as VOC. The enriched culture has a high affinity with 1,4-dioxane during biodegradation. The kinetic coefficients of the Monod equation were qmax = 0.0063 mg 1,4-D/mg VSS/h, Ks = 9.42 mg/L, YT = 0.43 mg VSS/mg 1,4-dioxane and the decay rate was kd = 0.023 mg/mg/h. Tetrahydrofuran (THF) and ethylene glycol were both consumed together with 1,4-dioxane by the enriched culture; however, ethylene glycol did not show any influence on 1,4-dioxane biodegradation, while THF proved to be a competitive.