Biodegrading Lignocellulosic Agricultural Waste using Phanerochaete chrysosporium and Electrical Current Stimulation

White-rot fungi (WRF), such as Phanerochaete chrysosporium, play a significant role in the lignin degradation (LD) of biomass, an essential process in the carbon recycling of terrestrial ecosystems. However, the rapid development of the agroindustry has imposed a daunting task on biomass waste management. One green initiative focuses on enhancing the bioremediation of lignin since it forms a resistant barrier to chemical and biological LD. This work demonstrated that electric current stimulation (ECS) can markedly enhance LD by P. chrysosporium. Palm oil empty fruit bunches (EFBs) were utilized as a lignin-rich substrate for P. chrysosporium. These were placed in a 250-ml enclosure filled with unbuffered potato dextrose broth (PDB) as the electrolyte. The ECS was supplied in situ in two ways: (1) by inserting a zinc anode/air electrode redox couple into the enclosure to produce a self-sustaining discharge current (DC), and (2) by connecting the enclosure to an external current (EC). The lignin content (LC) of the EFBs was assessed after 30 days of exposure to fungal microbes in an uncontrolled environment. The fungal LD rate was highest at 3 mA and even doubled under the influence of the EC, enhancing the lignin removal by 74.6%. The proposed method is much simpler and cheaper than the electrocatalytic reactions produced by the electro-Fenton method.