Microbial degradation of N,N-dimethylformamide by Paracoccus sp. strain DMF-3 from activated sludge

Abstract

N,N-dimethylformamide (DMF) was a typical toxic chemical and existed extensively in industrial wastewater. In this study, a strain of the high-efficient DMF degrading bacteria DMF-3 belonging to Paracoccus sp. was enriched and isolated from activated sludge. The removal rate of DMF by DMF-3 was up to 100% while 1000mg/L DMF was used as the sole carbon and nitrogen source. Growth kinetics model of DMF-3 was thus established, and the kinetic constants were determined with maximum specific growth rate μ max =0.22 (h-1), saturation constant Ks =0.41 (g/L) and inhibition constant Ki =25.93 (g/L). Based on the analysis of the intermediate products, it was found that DMF was firstly converted into dimethylamine and formic acid, and these intermediates were finally degraded to ammonia and carbon dioxide following the typical metabolic pathway of methylotrophs. In addition, to enhance the degrading capacity of DMF-3 in high DMF concentration, ultraviolet mutagenesis process was applied. Compared with the usage of the original strain of DMF-3, the degradation rate was increased by 14.8% with the usage of obtained mutant strain with applied initial DMF concentration 10000mg/L.

Zero valent iron enhances methane production from primary sludge in anaerobic digestion

“…However, different from the highest performance of anaerobic methane production from WAS at ZVI of 20 g/L [14], the highest methane production from PS was obtained at ZVI of 4 g/L, which might be attributed to the different sludge characteristics. WAS is the sludge produced by biological process and it mainly contains biomass and extracellular polymeric substances (EPS) [16,[29][30][31]. In contrast, PS is the sludge composed of settleable solids (e.g., feces, vegetables, etc)…”

Genomics-informed insights into microbial degradation ofN,N-dimethylformamide

“…Various physicochemical methods have been investigated to remove DMF from wastewater, including photocatalytic oxidation (8,9), plasma oxidation (10), catalytic wet oxidation (11,12), physical adsorption (13,14), membrane separation (15,16), and chemical extraction (17). Microbial degradation is considered to be a superior alternative as it is economical, eco-friendly, and highly efficient (18)(19)(20)(21)(22). So far, limited bacterial isolates are capable of utilizing DMF as the sole carbon and nitrogen source, including members of Paracoccus, Methylobacterium, Mesorhizobium, Ochrobactrum, Alcaligenes, Pseudomonas, Mycobacterium, and Bacillus (Table 1).…”

Zein nanofibers via deep eutectic solvent electrospinning: tunable morphology with super hydrophilic properties

“…With a full background of electrospinning development to project the question is use of several organic solvents such as Dimethylformamide (DMF) 1 , Chloroform 2 , Trifluoracetic-acid 3 and Tetra hydro-furan 4 . Electrospinning is developing from fluid blending process to fluid coaxial 1 and side-by-side 5 , and to tr-fluid coaxial 6 and other multi-fluid processes 7 , 8 . However, all these developments are based on the application of organic solvents for preparing working fluids, which is harmful to environment and health 9 .…”