Degradation of Polycyclic Aromatic Hydrocarbons by Consortium 5H Under Hypersaline Conditions

Abstract

PAHs were widely detected accumulated in saline and hypersaline environments. The halotolerant and halophilic microbes were considered as the most suitable player for the elimination of PAHs in such environments. In this study, consortium 5H was enriched under 5% salinity that was able to completely degrade phenanthrene in 5 days. By high-throughput sequencing, consortium 5H was identified mainly composed of Methylophaga, Marinobacter and Thalassospira. Combined with the investigation of intermediates and enzymatic activities, the degradation pathway of consortium 5H on phenanthrene was proposed. Meanwhile, consortium 5H was identified with ability to tolerate a wide range of salinity (1% to 10%) and initial PAHs concentration (50 mg/L to 400 mg/L). It was also able to work under neutral to week alkaline conditions (pH from 6 to 9) and the phytotoxicity of the produced intermediates showed no significant difference with distilled water. This study expanded the knowledge of PAH-degradation under hypersaline environments and consortium 5H was proposed with a good potential for the elimination of PAHs pollution under saline/hypersaline environments.

Reducing Organic Load From Industrial Residual Process Brine With a Novel Halophilic Mixed Culture: Scale-Up and Long-Term Piloting of an Integrated Bioprocess

“…Moreover, it was reported for co-cultivations of microorganisms, that productivities and process efficiencies can be improved, compared to monocultures ( Angell et al, 2006 ; Ishika et al, 2017 ; Anh et al, 2021 ). Moreover, the potential of halophilic consortia for the bioremediation of saline wastewater contaminated with organic impurities like aromatics was already proven in several cases ( Jamal and Pugazhendi, 2018 ; Al-Shaikh and Jamal, 2020 ; Jamal and Pugazhendi, 2021 ; Jin et al, 2021 ).…”