Efficient pyridine biodegradation by Stenotrophomonas maltophilia J2: Degradation performance, mechanism, and immobilized application for wastewater

• Published in: Journal of hazardous materials 2023-10, Vol.459, p.132220-132220, Article 132220
• Main Authors: Niu, Hongyu, Nie, Zimeng, Long, Yu, Guo, Jiayuan, Tan, Ju, Bi, Junping, Yang, Haijun
• Format: Article
• Language: English
• Subjects: bacteria; biochar; Biodegradation; bioremediation; butyric acid; Immobilized strain; Metabolic pathways; Pyridine; pyridines; Solidago canadensis; Stenotrophomonas maltophilia; temperature; wastewater; Wastewater bioremediation; wastewater treatment
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2023.132220

Stenotrophomonas maltophilia J2, a highly efficient pyridine-degrading bacterium, was isolated from the aerobic tank of a pesticide-contaminated wastewater treatment plant. The strain J2 demonstrated an impressive pyridine degradation rate of 98.34% ± 0.49% within 72 h, at a pyridine concentration of 1100 mg·L-1, a temperature of 30 °C, a pH of 8.0, and a NaCl concentration of 0.5%. Notably, two new pyridine metabolic intermediates, 1,3-dihydroxyacetone and butyric acid, were discovered, indicating that J2 may degrade pyridine through two distinct metabolic pathways. Furthermore, the immobilized strain J2 was obtained by immobilizing J2 with biochar derived from the stem of Solidago canadensis L. In the pyridine-contaminated wastewater bioremediation experiment, the immobilized strain J2 was able to remove 2000 mg·L-1 pyridine with a 98.66% ± 0.47% degradation rate in 24 h, which was significantly higher than that of the control group (3.17% ± 1.24%), and remained above 90% in subsequent cycles until the 27th cycle. High-throughput sequencing analysis indicated that the J2 +B group had an elevated relative abundance of bacteria and functional genes that could be associated with the degradation of pyridine. The results offer a foundation for the effective use of immobilized strain in the treatment of recalcitrant pyridine-contaminated wastewater. [Display omitted] •Stenotrophomonas maltophilia J2 was first isolated for pyridine degradation.•J2 achieved 98.34% pyridine degradation at 1100 mg·L-1 in 72 h at 30 °C and pH 8.0.•1,3-dihydroxyacetone and butyric acid was first found in pyridine biodegradation.•Immobilized strain J2 removed 98.66% degradation of 2000 mg·L-1 pyridine in 24 h.•J2 +B increased abundances of genera and genes related to pyridine degradation.