Production of ligninolytic enzymes by species assemblages of tropical higher fungi from Ecuador.

Resumen

The production of laccase and manganese peroxidase (Mp) by saprobic fungi (collected from Ecuador in September 1997) with different nutrient resource (wood and litter) was studied. Lower Mp activities (4.3 units) were detected in lignicolous fungal assemblage (Collybia bakeri, Lepiota lactea, Marasmius cladophyllus, Xeromphalina tenuipes, Favolaschia cinnabarina, Nothopanus eugrammus, Coltricia spathulata, Polyporus obolus, Polyporus leprieurii and Trametes ochracea) than in the litter assemblage (12.5 units; Cookeina tricholoma, Trametes maxima, Lentinus crinitus, Lentinus strigosus, Stereum insigne, Trametes corrugata, Xylaria guyanensis, Psathyrella albocapitata, Filoboletus gracilis and Tomentella lilacinogrisea). Five of the litter assemblage species had Mp titre values of >10 units (Collybia bakeri, M. cladophyllus, Polyporus obolus, Polyporus leprieurii and Trametes ochracea), while only Trametes maxima had a value of >10 units. The laccase titres of fungi from the lignicolous assemblage showed a significantly higher average laccase level (284.8 units) than those of the litter assemblage (6.4 units). While the highest titre of laccase activity in the litter assemblage was 18.2 units, Trametes maxima and Lentinus crinitus showed activities of more than 1000 units. Xylaria guyanensis and X. tenuipes had near zero values for both enzymes in culture filtrates. Both species grew well in the culture medium, and field data showed that both were highly effective in the in vivo degradation of lignocellulose (X. guyanensis of wood and X. tenuipes of litter).