title: Growth and production of laccases by the ligninolytic fungi, Pleurotus ostreatus and Botryosphaeria rhodina , cultured on basal medium containing the herbicide, Scepter (imazaquin).
abstract: The herbicide, Scepter, whose active principle is imazaquin, is commonly used in soybean farming to combat wide-leaf weeds. The basidiomycete, Pleurotus ostreatus , and the ascomycete, Botryosphaeria rhodina , were evaluated for their growth and laccase production when cultured on basal media containing Scepter. Both fungi could grow on the herbicide when cultivated in solid and submerged liquid culture in the presence of Scepter at concentrations of 0-6% (v/v) for P. ostreatus , and up to 0-50% (v/v) for B. rhodina , and in each case produced laccases when assayed against ABTS [2,2(1)-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid)] and 2,6-dimethoxyphenol. P . ostreatus could tolerate up to 6% of Scepter before it became toxic to the fungus, while in the case of B. rhodina , 50% (v/v) Scepter was the highest amount that supported grow, and laccase activity was detectable up to 25% (v/v). An inverse relationship existed between the level of Scepter in the culture medium that supported fungal growth and laccase production. Analysis of the results showed that the fungi studied presented different behaviour towards Scepter in the culture environment.
authors.affiliation: Departamento de Bioquímica e Biotecnologia (CCE ), Londrina - PR, Brazil.
authors.forename: Maria I
authors.initials: MI
authors.lastname: Rezende
authors.forename: Aneli M
authors.initials: AM
authors.lastname: Barbosa
authors.forename: Ana-Flora D
authors.initials: AF
authors.lastname: Vasconcelos
authors.forename: Renata
authors.initials: R
authors.lastname: Haddad
authors.forename: Robert F H
authors.initials: RF
authors.lastname: Dekker
mesh_terms: D001203:Ascomycota / Q000187:drug effects* / Q000201:enzymology / Q000254:growth & development*; D003470:Culture Media / Q000737:chemistry*; D006540:Herbicides / Q000494:pharmacology; D007093:Imidazoles / Q000378:metabolism / Q000494:pharmacology*; D042845:Laccase / Q000378:metabolism*; D008031:Lignin / Q000378:metabolism; D020076:Pleurotus / Q000187:drug effects* / Q000201:enzymology / Q000254:growth & development; D011804:Quinolines / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D003470:Culture Media; D006540:Herbicides; D007093:Imidazoles; D011804:Quinolines; C057728:imazaquin; D008031:Lignin; D042845:Laccase