Potensi Jamur Endofit Penghasil Enzim Lakase dari Daun Kelapa Sawit (Elaeis guineensis Jacq.)

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.