PRODUCTION OF LIGNINOLYTIC EXOENZYMES AND C-14 PYRENE MINERALIZATION BY PLEUROTUS SP. IN LIGNOCELLULOSE SUBSTRATE

Pleurotus sp. was grown in liquid medium and on a solid straw substrat e, and activities of laccase and manganese-dependent peroxidase (MnP) were recorded. The activities were the highest in a rich, glucose corn -steep liquid medium. In straw cultures, laccase activity was about te n times lower. Under solid state conditions, MnP production was the hi ghest during days 20-40, when laccase activity already had declined. I n straw cultures, mineralization of C-14-pyrene was measured as releas e of (CO2)-C-14. The highest rates of pyrene mineralization occurred d uring days 20-45, i.e. the period of high MnP activities, suggesting a role of this enzyme in PAH degradation. Within 60 d, 24 % of pyrene w as mineralized.