EXTRACTION OF LACCASE ENZYME PHANEROCHAETE CHRYSOSPORIUM IN RICE HUSK MEDIA FOR TOTAL PETROLEUM HYDROCARBON REDUCTION

Abstract

Total Petroleum Hydrocarbon (TPH) is a persistent soil contaminant that requires effective and sustainable remediation strategies. This study investigates the production and application of crude laccase enzyme from Phanerochaete chrysosporium cultivated using rice husk as a low-cost lignocellulosic substrate for TPH reduction in contaminated soil. Fungal cultures were initially propagated on PDA medium and subsequently transferred to PDB supplemented with rice husk under controlled conditions of 30°C and pH 7. Crude laccase was extracted using phosphate buffer, and its enzymatic activity was measured spectrophotometrically using ABTS as a substrate. After 14 days of incubation, laccase activity reached 24.49 U/L, with a maximum crude enzyme yield of 37.42%. The application of 15 mL of crude laccase extract to 5 g of contaminated soil reduced TPH concentration from 10% to 4.67%, achieving a removal efficiency of 53.3%. Laccase facilitates hydrocarbon degradation through oxidation reactions, particularly targeting aromatic and phenolic compounds. These findings demonstrate the potential of rice husk as an economical substrate for fungal laccase production and support the application of crude laccase as a promising approach for sustainable soil bioremediation. Further optimization of enzyme production and treatment conditions is recommended to enhance remediation efficiency.