Bioremediation of Crude Oil by Corynebacterium stationis CsPe-1: A Preliminary In Vitro Study

The present study evaluated the effect of two inoculum concentrations on the degradation of crude oil by Corynebacterium stationis CsPe-1. To this end, two treatment systems were utilized, each containing Davies Minimum Medium, 1% crude oil, and bacterial inoculum at concentrations of 10% and 15%, respectively. The degree of oil biodegradation was determined by evaluating the biochemical oxygen demand (BOD5), the chemical oxygen demand (COD), the concentration and fractions of oil and grease, and the total petroleum hydrocarbons (TPH). The results indicated that both BOD5 and COD exhibited an increase after a 20-day treatment period. For the 10% and 15% inoculum concentrations, a statistically significant difference was observed between the initial and final values of oils and fats (p < 0.05). In both systems, the levels of oils and fats decreased by 61%, contrasting with the control system, which exhibited minimal variation. A significant difference (p < 0.05) was observed in the degradation of TPH at the two inoculum concentrations. The findings indicated that the biodegradation of TPH was more efficient with an inoculum of 15%, resulting in a 79.94% reduction in fraction 3 (28–40 carbon chains). Fraction 1 exhibited less degradation, attributable to the toxicity of short-chain n-alkanes. Genomic analysis identified the pcaG and pcaH genes, which have been linked to the degradation of polycyclic aromatic hydrocarbons. This study underscores the biotechnological potential of strain CsPe-1 for the remediation of hydrocarbon-contaminated environments, thereby contributing to the realization of Sustainable Development Goals 14 and 15.