TY - JOUR
T1 - 4-Chlorophenol degradation by a bacterial consortium
T2 - development of a granular activated carbon biofilm reactor
AU - Caldeira, M.
AU - Heald, S. C.
AU - Carvalho, M. F.
AU - Vasconcelos, I.
AU - Bull, A. T.
AU - Castro, P. M. L.
PY - 1999
Y1 - 1999
N2 - A bacterial consortium that can degrade chloro- and nitrophenols has been isolated from the rhizosphere of Phragmitis communis. Degradation of 4- chlorophenol (4-CP) by a consortium attached to granular activated carbon (GAC) in a biofilm reactor was evaluated during both open and closed modes of operation. During the operation of the biofilm reactor, 4-CP was not detected in the column effluent, being either adsorbed to the GAC or biodegraded by the consortium. When 4-CP at 100 mg l-1 was fed to the column in open mode operation (20 mg g-1 GAC total supply), up to 27% was immediately available for biodegradation, the rest being adsorbed to the GAC. Biodegradation continued after the system was returned to closed mode operation, indicating that GAC bound 4-CP became available to the consortium. Biofilm batch cultures supplied with 10-216 mg 4-CP g-1 GAC suggested that a residual fraction of GAC-bound 4-CP was biologically unavailable. The consortium was able to metabolise 4-CP after perturbations by the addition of chromium (Cr VI) at 1-5 mg l-1 and nitrate at concentrations up to 400 mg l-1. The development of the biofilm structure was analysed by scanning electron microscopy and confocal laser scanning microscopy (CLSM) techniques. CLSM revealed a heterogeneous structure with a network of channels throughout the biofilm, partially occupied by microbial exopolymer structures.
AB - A bacterial consortium that can degrade chloro- and nitrophenols has been isolated from the rhizosphere of Phragmitis communis. Degradation of 4- chlorophenol (4-CP) by a consortium attached to granular activated carbon (GAC) in a biofilm reactor was evaluated during both open and closed modes of operation. During the operation of the biofilm reactor, 4-CP was not detected in the column effluent, being either adsorbed to the GAC or biodegraded by the consortium. When 4-CP at 100 mg l-1 was fed to the column in open mode operation (20 mg g-1 GAC total supply), up to 27% was immediately available for biodegradation, the rest being adsorbed to the GAC. Biodegradation continued after the system was returned to closed mode operation, indicating that GAC bound 4-CP became available to the consortium. Biofilm batch cultures supplied with 10-216 mg 4-CP g-1 GAC suggested that a residual fraction of GAC-bound 4-CP was biologically unavailable. The consortium was able to metabolise 4-CP after perturbations by the addition of chromium (Cr VI) at 1-5 mg l-1 and nitrate at concentrations up to 400 mg l-1. The development of the biofilm structure was analysed by scanning electron microscopy and confocal laser scanning microscopy (CLSM) techniques. CLSM revealed a heterogeneous structure with a network of channels throughout the biofilm, partially occupied by microbial exopolymer structures.
UR - http://www.scopus.com/inward/record.url?scp=0032726013&partnerID=8YFLogxK
U2 - 10.1007/s002530051584
DO - 10.1007/s002530051584
M3 - Article
C2 - 10570819
AN - SCOPUS:0032726013
SN - 0175-7598
VL - 52
SP - 722
EP - 729
JO - Applied Microbiology and Biotechnology
JF - Applied Microbiology and Biotechnology
IS - 5
ER -