Impacts of holmium and lithium to the growth of selected basidiomycetous fungi and their ability to degrade textile dyes

Abstract

The impacts of Ho and Li (0, 10, 50, 200 mg/L) were tested towards the growth of four basidiomycetous fungal species, their ability to decolorise synthetic dyes (Reactive Green 19, Reactive Orange 16, Reactive Black 5), and produce oxidative enzymes. All species;Agrocybe dura,Skeletocutis biguttulata,Exidia saccharinaandGalerina paludosa;grew with and without supplemented Ho or Li. The growth ofS. biguttulatawas the most tolerant species towards Ho or Li (200 mg/L), whereas the growth ofG. paludosawas the most sensitive of the studied species to both 200 mg Ho or Li/L. All fungi oxidized ABTS [2,2 '-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid)] forming colour zone on plate tests indicating production of lignin modifying laccase enzyme.A. duraandG. paludosa,formed black MnO(2)zone in Mn(2+)plates, which indicates the production of manganese peroxidase (MnP).A. duraandG. paludosadecolorised Reactive Black 5 indicating the production of versatile peroxide (VP) enzyme. Our study presents two new candidate species able to produce VP.A. durawas capable of decolorising all tested synthetic dyes in the presence of Ho or Li (0-200 mg/L) suggesting that this fungus is a promising species for bioremediation of multi dye-containing wastes.