Abstract:
This study is concerned with white-rot fungi isolation and screening processes.
The fungal collections were done in several parts of Thailand. The samples, such as
basidiocarp, pieces of dead and live tree that had been attacked by white-rot fungi,
were collected for isolation and screening for potent PAHs degrading strains. The
qualitative screening was performed in agar plates using polymeric dye as an
indicator. The fungi strains with observed clear zone were used for comparison of their
dye decolorizing activity to that of the reference strain, Trametes versicolor. The fungi
with similar or higher dye decolorizing activity than that of the reference were selected
for enzyme assays with Lignin peroxidase, Laccase, and manganese peroxidase, and
for benzo[a]pyrene degradation. The goal was to isolate the strains of white-rot fungi,
which were good degraders of contaminants.
109 strains of white-rot fungi were isolated. However, only 26 strains produced
clear zones in the qualitative assay. In the quantitative assay 10 fungi were selected, 7
strains showed a level of decolorizing activity comparable to that of the reference,
while 3 strains showed significantly higher activities. For the benzo[a]pyrene
degradation, K18 showed the highest degrading activity at 39.85%. The enzyme
assays showed that K18 had high level of Lignin peroxidase, Laccase, and manganese
peroxidase, which indicates that K18 has good potential as a degrader of PAHs. K18
was later identified as Phanerochaete sp.