Cometabolic degradation of chlorophenols by a strain of Burkholderia in fed-batch culture

• Published in: Enzyme and microbial technology Vol. 40; no. 1; pp. 57 - 60
• Main Authors: De Los Cobos-Vasconcelos, D., Santoyo-Tepole, F., Juárez-Ramírez, C., Ruiz-Ordaz, N., Galíndez-Mayer, C.J.J.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 06.12.2006; Elsevier Science
• Subjects: Biodegradation; Biological and medical sciences; Biotechnology; Biotransformation; Burkholderia; Burkholderia tropicalis; Chlorophenol; Cometabolism; Fed-batch; Fundamental and applied biological sciences. Psychology; Biodegradation; Chlorophenol; Fed-batch; Biotransformation; Cometabolism; Burkholderia tropicalis; Phenols; Bacteria; Burkholderia; Culture; Semicontinuous
• ISSN: 0141-0229; 1879-0909
• DOI: 10.1016/j.enzmictec.2005.10.038

This work deals with the study of mono and dichlorophenols degradation by a strain of Burkholderia isolated from the Santa Alejandrina marsh, Minatitlán, Veracruz, México. This strain also degrades benzene, toluene and xylene and was identified as the N 2-fixing bacteria Burkholderia tropicalis. In addition, the cometabolic degradation of 2-chlorophenol (2-CP), 4-chlorophenol (4-CP), 2,4-dichlorophenol (2,4-DCP) and 2,6-dichlorophenol (2,6-DCP) was evaluated in batch and fed-batch cultures, using phenol as the primary substrate. This bacterial strain was unable to degrade the highly substituted chlorophenols 2,4,5-TCP, 2,4,6-TCP and pentachlorophenol. Except for 4-CP, the cometabolic degradation of chlorophenols in batch culture was slow and inefficient, but when B. tropicalis was cultivated in fed-batch system, the removal efficiencies obtained were 93% for 2-CP, 95% for 2,6-DCP, 96% for 2,4-DCP and 100% for 4-CP. However, low cell growth yields were obtained in both batch and fed-batch cultures. This could be attributed to the uncoupling action of the aromatic compounds involved and, except for 2,6 DCP, to the accumulation of metabolic by-products.