Isolation, Identification And Characterization Of Triethylamine-Degrading Bacterial And The Application Of Immobilized R4Cells

A bacterial strain, capable of utilizing TEA (Triethylamine) as sole carbon and nitrogen source was isolated from activated sludge collected from wastewater treating pool of a pharmaceutical company. This strain was identified as Arthrobacter protophormiae according to its morphological, physiological and biochemical analysis and the analysis of its16S rRNA gene sequence, and named R4.The optimal growth temperature and pH of strain R4were30℃and7.0respectively. The liquid volume in flask showed a negative correlation with the growth of R4. Strain could grow well in the NaCl solution with the concentration of0-25g/L, and the optimum concentration of NaCl was5g/L. R4could utilize glucose, mannitol, sodium acetate, sodium formate as carbon source; ammonium sulfate and urea as nitrogen source; TEA,DEA(Diethylamine) and EA(Ethylamine) as sole carbon and nitrogen source but it could hardly utilize potassium nitrate, sodium nitrite and TMA(Trimethylamine).Strain R4could degrade100mg/L TEA within32h. Release of ammonia-nitrogen was equivalent to80%of the theroretical value of that100mg/L TEA was completely degraded to ammonia. The optimal pH and temperature for the degradation were7.0and30℃, respectively. The degrading rate showed a negative correlation with the liquid volume in flask and a positive correlation with the inoculum size. Addition of lmol/L Mg2+promote the degradation of TEA while Fe3+, Zn2+, Cu2+, Co2+, Ni2+and Ag+inhibited the degradation. Mn2+had little impact on the degradation. Addition of either SO42-or NH4-reduced the degradation efficiency of TEA to a certain extent. The inhibition became significant when the concentration of SO42-and NH4+reached11mM/L and30mM/L, respectively. Concentrations of Cl-higher than0.16mol/L were inhibitory to TEA biodegradation, and the optimum concentration of Cl-for TEA degradation by strain R4was0.08mol/L.By the result of MS analysis, we found that the intermediate material of TEA degradation were TEA N-oxide, DEA N-oxide,DEA,EA and metabolic end product is NH4+ DEA and EA could be degraded more rapidly than TEA. The cell-free extract exhibited TEA monooxygenase, DEA monooxygenase and EA monooxygenase activities in the TEA degradation pathway.The immobilized R4cells were taken to treat the TEA wastewater with fluidized-bed as the reactor. The optimum amount of imbedded balls was:imbedded ball/wastewater=175/1000. The concentration of TEA had great impact on the removal efficiency. The feasibility of reuse of immobilized R4cells for TEA degradation was evaluated. After four consecutive degradation experiments, the removal efficiency still achieved80%.