Abstract: To address the issue of biochemical degradation of N, N-dimethylacetamide （DMAc） in membrane wastewater, a bacterial strain designated DC-1, which is capable of effectively degrade DMAc, was isolated from the activated sludge of the Guiyang Maijiaqiao municipal wastewater treatment plant. Based on morphological observations, physiological and biochemical characterization, as well as phylogemetic analysis of the 16S rDNA gene sequence, it was identified asArthrobacter protophormiae. The effects of inoculum size, incubation temperature, and pH on the efficiency of DMAc degradation by DC-1 were investigated using a one-factor-at-a-time approach followed by response surface methodology based on the Box-Behnken design. The results indicated that the optimal temperature for bacterial growth and DMAc degradation was 29 ℃, the optimal pH was 7.8, and the optimal inoculum size was 13%. Under the optimized conditions, a degradation rate of over 90% was achieved for DMAc at an initial volume fraction of 2% within 144 h. Additionally, the strain exhibited certain degradation capabilities for the structurally similar compound dimethylformamide（DMF）. These findings demonstrated that strain DC-1 held considerable potential for the bioremediation of DMAc-contaminated wastewater, particularly in membrane manufacturing industries.

Key words: Arthrobacter protophormiae, degrading bacteria, membrane-making wastewater, N, N-dimethylacetamide, degradation characteristics