Fungal bioconversion of 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4-dichlorophenol (2,4-DCP).
Ninety strains of fungi from the collection of our mycology laboratory were tested in Galzy and Slonimski (GS) synthetic liquid medium for their ability to degrade the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) and its by-product, 2,4-dichlorophenol (2,4-DCP) at 100 mg l(-1), each. Evolution of the amounts of each chemical in the culture media was monitored by HPLC. After 5 days of cultivation, the best results were obtained with Aspergillus penicilloides and Mortierella isabellina for 2,4-D and with Chrysosporium pannorum and Mucor genevensis for 2,4-DCP. The data collected seemed to prove, on one hand, that the strains responses varied with the taxonomic groups and the chemicals tested, and, on the other hand, that 2,4-D was less accessible to fungal degradation than 2,4-DCP. In each case, kinetics studies with the two most efficient strains revealed that there was a lag phase of 1 day before the onset of 2,4-D degradation, whereas there was none during 2,4-DCP degradation. Moreover, 2,4-DCP was detected transiently during 2,4-D degradation. Finally, M. isabellina improved its degradation potential in Tartaric Acid (TA) medium relative to GS and Malt Extract (ME) media.
Vroumsia
T
T
Département des Sciences de l'Environment, Faculté des Sciences, Université de Ngaoundéré, B.P. 454 Ngaoundéré, Cameroun. tvroumsia@yahoo.fr
Steiman
R
R
Seigle-Murandi
F
F
Benoit-Guyod
J-L
JL
D015084:2,4-Dichlorophenoxyacetic Acid / Q000032:analysis / Q000378:metabolism*; D001673:Biodegradation, Environmental; D002733:Chlorophenols / Q000032:analysis / Q000378:metabolism*; D003470:Culture Media; D005658:Fungi / Q000378:metabolism*; D006540:Herbicides / Q000032:analysis / Q000378:metabolism*; D007700:Kinetics; D025282:Mycelium / Q000254:growth & development / Q000378:metabolism
D002733:Chlorophenols; D003470:Culture Media; D006540:Herbicides; D015084:2,4-Dichlorophenoxyacetic Acid; C004762:2,4-dichlorophenol