Biodegradation of Anthracene and Phenanthrene by Pseudomonas stutzeri (BUK_BTEG1) Isolated from Petrochemical Contaminated Soil

Abstract

Abstract The United States Environmental Protection Agency (USEPA) has identified 16 substances as priority polycyclic aromatic hydrocarbons (PAHs) that are harmful to humans, including anthracene and phenanthrene. These substances are pervasive pollutants introduced into the environment through anthropogenic and natural processes, causing ecological concerns and necessitating the quest for new strains capable of biodegrading these toxins. A novel strain of the genus Pseudomonas was isolated and molecularly identified based on partial 16S rRNA and phylogenetic analysis as Pseudomonas stutzeri strain BUK_BTEG1 from petrochemical contaminated soil. One factor at a time (OFAT) in Bushnell-Haas (BH) media was used to optimize the strain’s biodegradation conditions. The isolate could grow up to 600 mgL−1 and 400 mgL−1 of anthracene and phenanthrene as the sole carbon source at an optimum pH of 7.0 and 7.5 respectively, inoculum concentration of 4% (v/v), and temperature of 35°C during 72 hours of incubation. The strain could degrade phenanthrene and anthracene to a maximum of 99 and 72 percent, respectively, under ideal conditions. The breakdown products’ GC-MS analysis revealed the existence of the pathway’s main metabolites, catechol, salicylic acid, and derivatives of phthalic acid. The strain exhibits promising potential for use in the bio-cleansing of environments contaminated by PAHs.metabolites.