title: Lignin modifying enzymes of Coriolopsis polyzona and their role in olive oil mill wastewaters decolourisation.
abstract: In order to decolourise olive oil mill wastewaters (OOMW) efficiently, production and differential induction of ligninolytic enzymes by the white rot Coriolopsis polyzona, were studied by varying growth media composition and/or inducer addition. Among various possible inducers, veratryl alcohol appeared to be the most efficient to enhance specific productions of lignin peroxidase (LiP), manganese peroxidase (MnP) and laccase by a factor of 18.5, 20.8 and 55, respectively. Ligninolytic enzymes were better produced in glucose based medium with a low nitrogen level (2.2 mM) under O2 atmosphere. The addition of 5 mM veratryl alcohol resulted in a maximal production of LiP, whereas maximal MnP and laccase were obtained at 10 mM. LiP production was totally repressed in presence of 100 microM Mn2+. The extrapolation of these conditions on OOMW based media was carried out at different effluent dilutions and the possible role of the different ligninolytic enzymes in OOMW decolourisation was studied. A better effluent decolourisation was obtained under LiP induction condition (5 mM veratryl alcohol) than when LiP was repressed (100 microM Mn2+). Furthermore, high levels of laccase had a detrimental effect on OOMW decolourisation concomitant to the formation of soluble polymeric aromatic compounds.
authors.affiliation: Laboratoire de Physiologie et d'Ecologie Microbiennes, 642 Rue Engeland, 1180 Bruxelles, Belgium.
authors.forename: Atef
authors.initials: A
authors.lastname: Jaouani
authors.forename: Mohamed Ghazi
authors.initials: MG
authors.lastname: Tabka
authors.forename: Michel J
authors.initials: MJ
authors.lastname: Penninckx
mesh_terms: D001673:Biodegradation, Environmental; D002851:Chromatography, High Pressure Liquid; D019649:Food Industry; D008031:Lignin / Q000032:analysis*; D000069463:Olive Oil; D010100:Oxygen / Q000737:chemistry; D010938:Plant Oils; D020072:Polyporales / Q000201:enzymology* / Q000254:growth & development; D014874:Water Pollutants, Chemical / Q000032:analysis*; D018508:Water Purification / Q000379:methods*
chemical_list: D000069463:Olive Oil; D010938:Plant Oils; D014874:Water Pollutants, Chemical; D008031:Lignin; D010100:Oxygen