Wastewater produced from petroleum and coal processing industries can be contaminated with m-cresol and pyridine, which are two hazardous compounds with significant environmental and health effects. A bacterium known as Lysinibacillus cresolivorans has been demonstrated to effectively biodegrade m-cresol and this bacterium has been utilised by researchers to study the interaction effects of m-cresol and pyridine. Some variations in the literature were observed in the experimental data of the biodegradation of pyridine, which may be attributed to inaccurate estimation of initial cell mass concentration. In this work, simulations were run in combination with an algorithm to optimise initial biomass cell concentrations to describe the biodegradation kinetics of an inhibitory system in relation to experimental data. Simulated data on predicted cell concentrations and the results of this study may facilitate full-scale bioreactor design for m-cresol and pyridine removal from wastewater resulting from petroleum and coal processing.