In recent years, many studies have been developed to overcome the abundance of lignocellulosic waste. Laccase is a metalloenzyme that can degrade lignin. This enzyme has useful properties that make it applicable for the agricultural sector in Indonesia. The present study is designed to isolate and determine the activity of laccase found in the fungi of oil palm empty fruit bunch (OPEFB), and the fungal laccase was precipitated and partially purified by using ammonium sulfate. The optimum temperature of fungal laccase was 40 °C for fungus lacc-B and 50 °C for fungus lacc-A, C, and D. The optimum pH was obtained 5.0 for fungus lacc-A and D, pH 6.0 for fungus lacc-C and pH 7.0 for fungus lacc-B. Furthermore, the activity of crude extract were 1.4 U.mL−1, 1.5 U.mL−1, 1.3 U.mL−1, and 1.3 U.mL−1 for fungus lacc-A, B, C, and D. Purification levels of fungus lacc-A, B, C, and D increased 1.7, 1.6, 1.9, and 2.5 times, respectively after ammonium sulfate precipitation and dialysis. Fungus lacc-D has the highest level of laccase activity than other fungi. Physical analysis of the agricultural waste after fungus lacc-D addition indicated that the surface profile is damaged, hollow, and broken. The delignification from corn cob and rice straw was observed with scanning electron microscope (SEM) which showed the presence of morphological changes in the lignocellulose waste sample.
- Scanning electron microscope