Effect of different carbon and nitrogen regimes on Poly R decolorization by white-rot fungi

Abstract

Production of lignin-modifying enzymes by 10 white-rot fungi, as measured by decolorization of Poly R 478 dye, varied in response to different carbon and nitrogen regimes. Fastest decolorization rates were achieved with wood polysaccharide monomers (glucose, xylose) as carbon source, although cellulose was the only carbon source to facilitate decolorization by all test fungi. Enzyme production by most isolates was strongly dependant on nitrogen levels, with high nitrogen conditions generally suppressing enzyme production. One unidentified isolate (HKUCC 4062) displayed apparent nitrogen deregulation of enzyme production. A cellulose-low nitrogen growth medium is recommended for agar-based screening procedures of lignin-modifying enzyme production by white-rot fungi.