<p>Microbial fuel cells (MFC) are a popular method for degrading pollutants while generating energy. Additionally, oil palm trunk sap (OPTS) has been identified as an organic substrate for electron generation in literature. This substrate addresses challenges in selecting suitable organic materials for MFC. The instability of the organic substrate impacts the generation of electrons, one of the key challenges in MFC operation. Over 50 days of operation, a power density of 16.72 mW m⁻² was achieved, and the biodegradation efficiency of <i>p</i>-cresol reached 83.33%. On the 50th day, electrochemical findings revealed a specific capacitance of 0.00007&#xa0;F g⁻¹ and a total internal resistance of 336.81 ῼ. The anode surface has been shown to be dominated by <i>Providencia rettgeri</i>, which plays an important role in pollution treatment, using 16&#xa0;S rRNA sequencing and primary isolation. This work also investigates the basic processes of organic substrate oxidation and pollutant biodegradation. Furthermore, it briefly discusses the main challenges to the commercialization of this technique.</p> Graphical Abstract <p></p>