Bioactive compounds from discarded mushroom beds

Discarded dried button, dried oyster, and fresh button mushroom beds were examined for their bioactive compounds and industrial enzymes. Levels of reducing sugars and total sugars were high in all mushroom beds. Carboxymethyl cellulase activity was higher (920 μg/mL) in the dried oyster mushroom bed extract. Schizophyllum commune, Fomitopsis feei, Trametes gibbosa, and Trametes elegans were grown on direct mushroom bed extract, 0.2% glucose-containing mushroom bed extract, and common production medium for determination of growth and lignolytic activities. Since lignolytic activities were high with the direct mushroom bed extract, this medium was further diluted to 1:1 and 1:2 ratios and again tested for growth and lignolytic activities with F. feei, T. gibbosa, and T. elegans. It was determined that the 1:1 ratio gave good results for all these organisms. The button mushroom bed extract was concentrated using a rotary evaporator and compared for growth and lignolytic enzymes with dried powder extract using F. feei, T. gibbosa, and T. elegans. Growth was high with these 3 organisms in the dried powder extract, but lignin peroxidase activity was the highest with the rotary evaporator extract using T. gibbosa. The results indicate that these waste mushroom bed extracts can be used as cost-effective media for the growth of microorganisms and for the production of bioactive compounds and industrial enzymes.