Biodegradation of 2,4-dichlorophenol by a Bacillus consortium

• Published in: World journal of microbiology & biotechnology 2008, Vol.24 (1), p.55-60
• Main Authors: Herrera, Yesenia, Okoh, Anthony I, Alvarez, Laura, Robledo, Norma, Trejo-Hernández, María R
• Format: Article
• Language: English
• Subjects: 2,4-dichlorophenol; Aerobic biodegradation; Applied Microbiology; Bacillus; Bacillus consortium; Bacteria; Biochemistry; Biodegradation; Biological and medical sciences; Biomedical and Life Sciences; Bioremediation; Biotechnology; Chlorophenol; Environmental Engineering/Biotechnology; Fundamental and applied biological sciences. Psychology; Life Sciences; Microbiology; Nitrogen source; Nitrogen sources; Original Paper; Soil pollution; Xenobiotics
• ISSN: 0959-3993; 1573-0972
• DOI: 10.1007/s11274-007-9437-0

As part of our effort at establishing microbial consortia of relevance for the bioremediation of xenobiotics polluted environments in Mexico, we assessed the aerobic biodegradation of 2,4-dichlorophenol (2,4-DCP) by a consortium of four Bacillus species that were isolated from a polluted soil by enrichment using a mixture of chlorophenols. The bacterial consortium effectively biodegraded 2-chlorophenol, 3-chlorophenol and 2,4-dichlorophenol at degradation rates of between 1.7 and 6.7 μmoles l-¹ h-¹. In the presence of NH₄Cl or KNO₂ as nitrogen sources, 2,4-DCP was variously degraded. Under both conditions, cell biomass attained highest values of 350 and 450 mg l-¹ respectively, while the amounts of 2,4-DCP metabolized in 21 days reached peak values of 2.1 and 2.5 mM representing between 70 and 85% degradation respectively. Chloride releases during the same period were highest at 4.7 mM and 5.3 mM in the presence of the two nitrogen sources. The presence of free-chloride in the culture medium had a significant impact on the catabolism of 2,4-dichlorophenol.