| dc.description.abstract | Oil palm leaves as habitat for various endophytic fungi that have the potential
to produce hydrolytic enzymes, including lignin-degrading laccase enzymes. This
study aimed to determine the potential of endophytic fungi isolated from palm oil
leaves to produce laccase enzymes. Endophytic fungi were isolated from palm oil
leaves collected from plantations in Medan Johor District. The fungal isolates
obtained were then characterized macroscopically and microscopically. The ability of
endophytic fungi to produce laccase enzymes was qualitatively and quantitatively
screened using 0.04% guaiacol. One unit of laccase activity was defined as the amount
of enzyme required to oxidize 1 µmol of guaiacol per minute. Laccase enzyme
production was tested in Potato Dextrose Broth (PDB) media with and without the
addition of corn cob powder. Potential laccase-producing endophytic fungi were
identified molecularly using ITS1 and ITS4 primers. A total of 12 endophytic fungal
isolates were obtained, showing diverse morphological characteristics, and
microscopically, almost all isolates exhibited septate hyphae. Qualitative screening
revealed three fungal isolates capable of producing laccase enzymes, indicated by
color changes in agar medium containing 0.04% guaiacol substrate, namely isolates
JED 08, JED 09, and JED 12. Quantitatively, laccase activity among the three isolates
ranged from 1.51 to 2.22 U/mL, with the highest activity recorded in isolate JED 08.
Laccase production in media supplemented with corn cob powder showed lower
specific activity compared to pure PDB media. Molecular identification showed that
isolate JED 08 had 99.64% similarity with Diaporthe tulliensis. The endophytic fungus
Diaporthe tulliensis JED 08 from palm oil leaves has potential as a laccase-producing
organism. | en_US |
