[Isolation of wood-decaying fungi and evaluation of their enzymatic activity (Quindío, Colombia)].
White rot fungi (Ascomycota and Basidiomycota) were collected on fallen trunks with different decay stages, in a subandean forest (La Montaña del Ocaso nature reserve), and it was evaluated their ligninolitic activity. They were cultured on malt extract agar. Then it was performed semiquantitative tests for laccase and cellobiose dehydrogenase (CDH) activity using ABTS and DCPIP as enzymatic inducers. Based on the results of these tests, the fungi with higher activities from trunks with different decay stages were selected: Cookeina sulcipes (for stage 1), a fungus from the family Corticiaceae (for stage 2), Xylaria polymorpha (for stage 3) and Earliella sp. (for stage 4). A fermentation was performed at 28 degrees C, during 11 days, in a rotatory shaker at 150 rpm. Biomass, glucose, proteins and enzyme activities measurements were performed daily. The fungi that were in the trunks with decay states from 1 to 3, showed higher laccase activity as the state of decay increased. A higher DCH activity was also associated with a higher. Also, there was a positive relationship between both enzymes' activities. Erliella was the fungus which presented the highest biomass production (1140,19 g/l), laccase activity (157 UL(-1)) and CDH activity (43,50 UL(-1)). This work is the first report of laccase and CDH activity for Cookeina sulcipes and Earliella sp. Moreover, it gives basis for the use of these native fungi in biotechnological applications and the acknowledgment of their function in the wood decay process in native forest.
Laboratorio de Ecología de Suelos y Hongos Tropicales, Departamento de Biología, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá D.C., Colombia.
Deisy Fernanda
DF
Chaparro
Diana Carolina
DC
Rosas
Amanda
A
Varela
D001203:Ascomycota / Q000201:enzymology / Q000302:isolation & purification; D001487:Basidiomycota / Q000201:enzymology / Q000302:isolation & purification; D018533:Biomass; D002237:Carbohydrate Dehydrogenases / Q000032:analysis*; D003105:Colombia; D005656:Fungal Proteins / Q000032:analysis*; D005658:Fungi / Q000201:enzymology / Q000302:isolation & purification*; D042845:Laccase / Q000032:analysis*; D013045:Species Specificity; D014934:Wood / Q000382:microbiology*
D005656:Fungal Proteins; D002237:Carbohydrate Dehydrogenases; C019859:cellobiose-quinone oxidoreductase; D042845:Laccase