title: Microbial activities in hydrocarbon-laden wastewaters: Impact on diesel fuel stability and the biocorrosion of carbon steel.
abstract: Anaerobic hydrocarbon biodegradation not only diminishes fuel quality, but also exacerbates the biocorrosion of the metallic infrastructure. While successional events in marine microbial ecosystems impacted by petroleum are well documented, far less is known about the response of communities chronically exposed to hydrocarbons. Shipboard oily wastewater was used to assess the biotransformation of different diesel fuels and their propensity to impact carbon steel corrosion. When amended with sulfate and an F76 military diesel fuel, the sulfate removal rate in the assay mixtures was elevated (26.8μM/d) relative to incubations receiving a hydroprocessed biofuel (16.1μM/d) or a fuel-unamended control (17.8μM/d). Microbial community analysis revealed the predominance of Anaerolineae and Deltaproteobacteria in F76-amended incubations, in contrast to the Beta- and Gammaproteobacteria in the original wastewater. The dominant Smithella-like sequences suggested the potential for syntrophic hydrocarbon metabolism. The general corrosion rate was relatively low (0.83 - 1.29±0.12mpy) and independent of the particular fuel, but pitting corrosion was more pronounced in F76-amended incubations. Desulfovibrionaceae constituted 50-77% of the sessile organisms on carbon steel coupons. Thus, chronically exposed microflora in oily wastewater were differentially acclimated to the syntrophic metabolism of traditional hydrocarbons but tended to resist isoalkane-laden biofuels.
authors.affiliation: Department of Microbiology and Plant Biology, University of Oklahoma, Norman, USA.
authors.forename: Renxing
authors.initials: R
authors.lastname: Liang
authors.affiliation: Department of Microbiology and Plant Biology, University of Oklahoma, Norman, USA.
authors.forename: Kathleen E
authors.initials: KE
authors.lastname: Duncan
authors.affiliation: Departamento de Procesos y Tecnología, Universidad Autónoma Metropolitana-Cuajimalpa, Mexico.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Le Borgne
authors.affiliation: Department of Microbiology and Plant Biology, University of Oklahoma, Norman, USA.
authors.forename: Irene
authors.initials: I
authors.lastname: Davidova
authors.affiliation: Institute for Coastal Marine Environment (IAMC) - CNR U.O.S. of Messina, Spianata San Raineri 86, 98121 Messina, Italy; Immanuel Kant Baltic Federal University, Kaliningrad, Russia.
authors.forename: Michail M
authors.initials: MM
authors.lastname: Yakimov
authors.affiliation: Department of Microbiology and Plant Biology, University of Oklahoma, Norman, USA. Electronic address: jsuflita@ou.edu.
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Suflita
mesh_terms: D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000378:metabolism; D002244:Carbon; D003343:Corrosion; D004269:DNA, Bacterial / Q000032:analysis; D005742:Gasoline; D006838:Hydrocarbons / Q000378:metabolism; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012767:Ships; D013232:Steel / Q000737:chemistry*; D062065:Wastewater / Q000382:microbiology*
chemical_list: D002244:Carbon; D004269:DNA, Bacterial; D005742:Gasoline; D006838:Hydrocarbons; D012336:RNA, Ribosomal, 16S; D013232:Steel; D062065:Wastewater
keywords: Biocorrosion; Biodegradation; Biofilm; Carbon steel; Diesel fuels; Syntrophy