Optimization and characterization of lignosulfonate biodegradation process by a bacterial strain, Sphingobacterium sp. HY-H

• Published in: International biodeterioration & biodegradation 2013-11, Vol.85, p.365-371
• Main Authors: Wang, Dongqi, Lin, Yishan, Du, Wenjing, Liang, Jidong, Ning, Youfeng
• Format: Article
• Language: English
• Subjects: ammonium chloride; Bacteria; Bacterial degradation; Biodegradation; biofuels; carbon dioxide; Degradation; Fourier transform infrared spectroscopy; gas chromatography-mass spectrometry; lignocellulose; Lignosulfonate; Lignosulfonates; Metabolic products; nitrogen; Optimization; pulp and paper mill effluents; Spectra; Sphingobacterium; Sphingobacterium sp; Strain; Taguchi's orthogonal array; temperature; Waste water
• ISSN: 0964-8305; 1879-0208
• DOI: 10.1016/j.ibiod.2013.06.032

The objective of this study was to investigate the optimization and pathways of lignosulfonate biodegradation by a newly isolated lignin-degrading bacterial strain, Sphingobacterium sp. HY-H. The optimal conditions for lignosulfonate degradation capability were determined by Taguchi's orthogonal matrix method to be: initial pH, 7.0; temperature, 30 °C; and a lignosulfonate/nitrogen (as NH4Cl) mass ratio of 5. Under optimal conditions, the maximum lignosulfonate degradation capacity of strain HY-H was 31%. In order to characterize the changes in residual lignosulfonate and the metabolic products, FTIR spectra, functional groups, and elemental and GC–MS analysis were introduced. An examination of the data suggests a possible route of lignosulfonate degradation by strain HY-H was that lignosulfonate was first depolymerized to low-molecular-weight compounds; then the side chains of lignosulfonate were partially oxidized and further decarboxylated to produce carbon dioxide. If properly optimized and controlled, strain HY-H may play a role in the treatment of pulp and paper wastewater containing a high concentration of lignosulfonate, as well as in the lignocellulose breakdown for biofuel and chemicals production. •The lignosulfonate-degrading process of Sphingobacterium sp. HY-H were optimized.•Strain HY-H grows fast in a wide range of lignosulfonate concentrations.•Hydroxy oxidation, demethylation and decarboxylation occurred in degradation process.•Possible mechanisms of lignosulfonate biodegradation by strain HY-H were speculated.