Tolerance and Biodegradation of High Concentration of Phenol by a Bacterial Consortium Enriched From the Hurricane Ida Sediment

Abstract

The purpose of this study was to measure the efficiency of a bacterial consortium's ability to degrade high concentrations of phenol. The consortium was obtained from sediment that was deposited on the residential properties in southeastern Louisiana after Hurricane Ida in August 2021. A bacterial consortium was developed through an enrichment technique that used phenol as the sole carbon source. Phenol degradation followed a concentration gradient. The consortium was able to remove more than 95% of phenol within 14 days when the phenol concentration was 100 mg/L. However, phenol degradation efficiency decreased when the phenol concentration was increased in the culture medium. The consortium removed 30% of phenol at the highest concentration tested, 1000 mg/L, within 14 days. However, when the incubation time was extended to 70 days, 98% phenol removal was observed in the highest concentration of phenol tested of 1000 mg/L. The consortium was dominated by three distinct phyla and nine distinct genera. The dominant phylum was represented by proteobacteria, and the dominant genus in the consortium was Shigella. The consortium removed phenol via the β-ketoadipate pathway with the production of the following metabolites: cis, cis-muconic acid, succinate, and fumarate. The novelty of this study was the high tolerance of phenol concentration of 1000 mg/L by the bacterial consortium and its ability to degrade phenol without a lag phase. This is one of the highest phenol concentrations reported in the literature. This consortium may be useful in the removal of high concentrations of phenol from the environment.