Biodegradation of sodium benzoate by a Gram-negative consortium in a laboratory-scale fluidized bed bioreactor

• Published in: Bioresource technology Vol. 99; no. 11; pp. 5115 - 5119
• Main Authors: Lindsay, D., Ntoampe, M., Gray, V.M.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.07.2008; [New York, NY]: Elsevier Ltd; Elsevier Science
• Subjects: Biodegradation; Biodegradation, Environmental; Biofilm; Biofilms; Biological and medical sciences; Bioreactors; Biotechnology; Colony Count, Microbial; DNA, Ribosomal - genetics; Fluidized bed bioreactor; Fundamental and applied biological sciences. Psychology; Gram-Negative Bacteria - growth & development; Gram-Negative Bacteria - isolation & purification; Gram-Negative Bacteria - metabolism; Gram-Negative Bacteria - physiology; Methods. Procedures. Technologies; Phylogeny; Pseudomonas; Pseudomonas - growth & development; Pseudomonas - isolation & purification; Pseudomonas - metabolism; Pseudomonas - physiology; Pseudomonas aeruginosa; Sodium Benzoate - metabolism; Various methods and equipments; Biodegradation; Fluidized bed bioreactor; Biofilm; Fluidized bed reactor; Benzoate; Bioreactor; Sodium; Laboratory scale; Gram negative bacteria
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2007.09.020

Gram-negative bacteria with the potential to metabolize n-alkanes and cyclic hydrocarbons were isolated from local soils and identified using 16S rDNA sequence analysis. Three isolates (CS1CO, GL1CO, GCI1CO) were identified as strains of Pseudomonas ( P.) aeruginosa and a further strain (DSS2) as P. putida. Isolates were co-cultured in a laboratory-scale fluidized bed biofilm bioreactor (FBBR) utilizing sodium benzoate as the sole carbon source, under two batch and/or one continuous growth conditions. Biofilm and planktonic bacterial growth dynamics were monitored by plate counts, and optical density measurements (230 nm) determined benzoate biodegradation. Overall higher attached and planktonic bacterial counts, and benzoate depletion, were determined under batch compared to continuous conditions, and the bioreactor performed better during the second batch phase when compared to the first batch phase. It thus appeared that both the planktonic and biofilm components of the system were necessary for the most successful sodium benzoate degradation in this system.