Precision modelling of co-metabolic biodegradation of recalcitrant aromatic hydrocarbons in conjunction with experimental data

Abstract

The co-metabolic biodegradation of p-xylene (as a non-growth substrate model) by Pseudomonas putida (well-known aromatic compounds degrading microorganism) in the presence of Benzene (B), Toluene (T), and Ethylbenzene (E) was studied. Michaelis-Menten/Monod kinetics coupled with co-metabolic degradation expression can be applied for systems containing one growth and one non-growth substrate; thus, the GMDH Group Method of Data Handling (GMDH) was proposed in this study to predict the co-metabolic transformation of non-growth substrates in the presence of more than one growth substrate. Thus, the GMDH Group Method of Data Handling (GMDH) was proposed for the first time to quantify p-xylene degradation (with < 10 % deviation) for the co-metabolic system. GMDH could predict the biomass and p-xylene concentration changes in the co-metabolic system without the need for kinetic and interaction parameter determination, while the determination of these parameters is needed for Michaelis-Menten/Monod model. Furthermore, mass balance and enzyme study confirmed the co-metabolic biodegradation of p-xylene in the presence of growth-substrates. This study proved the potential use of the GMDH model for the prediction of co-metabolic degradation; however, further study is needed for other non-growth contaminants to generalize this model.