The biodegradation of the monoazo-sulphonic dye Acid Orange 7 by means of Pseudomonas sp. OX1 has been investigated. Conversion was carried out in both gas-sparged flasks and in internal loop airlift reactors under controlled operating conditions at dye concentration up to 0.8 g/L. Luria-Bertani or synthetic culture media were used. Bioremediation was accomplished by a sequence of aerobic and anaerobic phases. Cell growth took place only during the aerobic phase. Dye conversion occurred only during the anaerobic phase, according to a Michaelis-Menten type kinetics. The maximum extent of decolorization is closely correlated with the amount of substrate carbon converted during the preceding aerobic phase: a limiting conversion of 70 mgdye per gram of substrate carbon was measured whatever the carbon source. The study has been successfully pursued further to explore the potential of a decolorization process based on cyclic aerobic-anaerobic operation of an airlift bioreactor. Whatever the initial dye concentration, dye depletion is achieved provided that optimal cyclic aerobic-anaerobic operating conditions are selected.
Azo-dye Conversion by means of Pseudomonas sp. OX1 / A., Lodato; Alfieri, Fabiana; Olivieri, Giuseppe; DI DONATO, Alberto; Marzocchella, Antonio; Salatino, Piero. - In: ENZYME AND MICROBIAL TECHNOLOGY. - ISSN 0141-0229. - STAMPA. - 41:(2007), pp. 646-652. [10.1016/j.enzmictec.2007.05.017]
Azo-dye Conversion by means of Pseudomonas sp. OX1
ALFIERI, FABIANA;OLIVIERI, GIUSEPPE;DI DONATO, ALBERTO;MARZOCCHELLA, ANTONIO;SALATINO, PIERO
2007
Abstract
The biodegradation of the monoazo-sulphonic dye Acid Orange 7 by means of Pseudomonas sp. OX1 has been investigated. Conversion was carried out in both gas-sparged flasks and in internal loop airlift reactors under controlled operating conditions at dye concentration up to 0.8 g/L. Luria-Bertani or synthetic culture media were used. Bioremediation was accomplished by a sequence of aerobic and anaerobic phases. Cell growth took place only during the aerobic phase. Dye conversion occurred only during the anaerobic phase, according to a Michaelis-Menten type kinetics. The maximum extent of decolorization is closely correlated with the amount of substrate carbon converted during the preceding aerobic phase: a limiting conversion of 70 mgdye per gram of substrate carbon was measured whatever the carbon source. The study has been successfully pursued further to explore the potential of a decolorization process based on cyclic aerobic-anaerobic operation of an airlift bioreactor. Whatever the initial dye concentration, dye depletion is achieved provided that optimal cyclic aerobic-anaerobic operating conditions are selected.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.