Kinetic growth model and metabolic effect of a bacterial consortia from a petrochemical processing plant

Abstract

This study focused on presenting the newly developed growth model for bacterial species present in a petrochemical processing plant in South Africa. The findings of the study serve as a theoretical basis for future experiments aimed at understanding the formation of bacterial metabolites as the bacteria develops. An unstructured kinetic model using AQUASIM 2.3, together with experimental spectrophotometric results, were used to evaluate the growth of Gram-negative bacteria in a batch reactor system. Spectrophotometer results showed the absence of a stationary phase. The exponential bacterial growth phase supported the total organic carbon (TOC) results, showing that bacterial growth occurred on days 6 and 13; this is rarely reported in literature, as the growth in this system was much slower than the growth of single-strain studies. The TOC concentration values indicated that carbon sources did not deplete in the death phase, suggesting the presence of a long-term stationary phase and the production of acetate. The presence of Pseudomonas sp. and sulphate-reducing bacteria (SRB) are commonly reported in industrial systems as they play a role in equipment failure in industry. However, in this multispecies study, methods using third generation sequencing together with high-performance liquid chromatography (HPLC) have shown that the selective attachment and production of acetate by abundant Clostridium sp. has ascertained their role in equipment failures in the petrochemical environment.