title: Allochthonous bioaugmentation in ex situ treatment of crude oil-polluted sediments in the presence of an effective degrading indigenous microbiome.
abstract: Oil-polluted sediment bioremediation depends on both physicochemical and biological parameters, but the effect of the latter cannot be evaluated without the optimization of the former. We aimed in optimizing the physicochemical parameters related to biodegradation by applying an ex-situ landfarming set-up combined with biostimulation to oil-polluted sediment, in order to determine the added effect of bioaugmentation by four allochthonous oil-degrading bacterial consortia in relation to the degradation efficiency of the indigenous community. We monitored hydrocarbon degradation, sediment ecotoxicity and hydrolytic activity, bacterial population sizes and bacterial community dynamics, characterizing the dominant taxa through time and at each treatment. We observed no significant differences in total degradation, but increased ecotoxicity between the different treatments receiving both biostimulation and bioaugmentation and the biostimulated-only control. Moreover, the added allochthonous bacteria quickly perished and were rarely detected, their addition inducing minimal shifts in community structure although it altered the distribution of the residual hydrocarbons in two treatments. Therefore, we concluded that biodegradation was mostly performed by the autochthonous populations while bioaugmentation, in contrast to biostimulation, did not enhance the remediation process. Our results indicate that when environmental conditions are optimized, the indigenous microbiome at a polluted site will likely outperform any allochthonous consortium.
authors.affiliation: School of Environmental Engineering, Technical University of Crete, Chania, Greece; King Abdullah University of Science and Technology, Thuwal, Saudi Arabia.
authors.forename: S
authors.initials: S
authors.lastname: Fodelianakis
authors.affiliation: School of Environmental Engineering, Technical University of Crete, Chania, Greece.
authors.forename: E
authors.initials: E
authors.lastname: Antoniou
authors.affiliation: Department of Food, Environment and Nutritional Sciences, University of Milan, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Mapelli
authors.affiliation: EcoTechSystems S.r.l., Italy.
authors.forename: M
authors.initials: M
authors.lastname: Magagnini
authors.affiliation: School of Environmental Engineering, Technical University of Crete, Chania, Greece.
authors.forename: M
authors.initials: M
authors.lastname: Nikolopoulou
authors.affiliation: King Abdullah University of Science and Technology, Thuwal, Saudi Arabia; Department of Food, Environment and Nutritional Sciences, University of Milan, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Marasco
authors.affiliation: Department of Food, Environment and Nutritional Sciences, University of Milan, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Barbato
authors.affiliation: Hellenic Center for Marine Research, Heraklion, Crete, Greece.
authors.forename: A
authors.initials: A
authors.lastname: Tsiola
authors.affiliation: Hellenic Center for Marine Research, Heraklion, Crete, Greece; Department of Biology, University of Crete,Heraklion, Crete, Greece.
authors.forename: I
authors.initials: I
authors.lastname: Tsikopoulou
authors.affiliation: EcoTechSystems S.r.l., Italy.
authors.forename: L
authors.initials: L
authors.lastname: Giaccaglia
authors.affiliation: LR11-ES31 Biotechnology and Bio-Geo Resources Valorization, Higher Institute for Biotechnology, Biotechpole SidiThabet, University of Manouba, 2020 Ariana, Tunisia.
authors.forename: M
authors.initials: M
authors.lastname: Mahjoubi
authors.affiliation: Laboratory of Microorganisms and Active Biomolecules, Faculty of Sciences of Tunis, University of Tunis El Manar, 2092 Tunis, Tunisia.
authors.forename: A
authors.initials: A
authors.lastname: Jaouani
authors.affiliation: Genetic Engineering and Biotechnology Research Institute, City for Scientific Research and Technology Applications (SRTA-City), Alexandria, Egypt.
authors.forename: R
authors.initials: R
authors.lastname: Amer
authors.affiliation: Department of Biological Sciences, Yarmouk University, 211-63 Irbid, Jordan.
authors.forename: E
authors.initials: E
authors.lastname: Hussein
authors.affiliation: Faculty of Marine Sciences, The University of Jordan-Aqaba, 7110 Aqaba, Jordan.
authors.forename: F A
authors.initials: FA
authors.lastname: Al-Horani
authors.affiliation: Laboratory of Microbiolgy, Biotechnology and Environmrent, University Hassan II Casablanca, Faculty of Sciences aîn-chock, B.P. 5366 Morocco.
authors.forename: F
authors.initials: F
authors.lastname: Benzha
authors.affiliation: Laboratory of Microbiolgy, Biotechnology and Environmrent, University Hassan II Casablanca, Faculty of Sciences aîn-chock, B.P. 5366 Morocco.
authors.forename: M
authors.initials: M
authors.lastname: Blaghen
authors.affiliation: Department of Biological Sciences, Yarmouk University, 211-63 Irbid, Jordan; Hamdan Bin Mohammed Smart University, Academic City, Dubai, United Arab Emirates.
authors.forename: H I
authors.initials: HI
authors.lastname: Malkawi
authors.affiliation: Genetic Engineering and Biotechnology Research Institute, City for Scientific Research and Technology Applications (SRTA-City), Alexandria, Egypt.
authors.forename: Y
authors.initials: Y
authors.lastname: Abdel-Fattah
authors.affiliation: LR11-ES31 Biotechnology and Bio-Geo Resources Valorization, Higher Institute for Biotechnology, Biotechpole SidiThabet, University of Manouba, 2020 Ariana, Tunisia; Laboratory of Microorganisms and Active Biomolecules, Faculty of Sciences of Tunis, University of Tunis El Manar, 2092 Tunis, Tunisia.
authors.forename: A
authors.initials: A
authors.lastname: Cherif
authors.affiliation: King Abdullah University of Science and Technology, Thuwal, Saudi Arabia; Department of Food, Environment and Nutritional Sciences, University of Milan, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Daffonchio
authors.affiliation: School of Environmental Engineering, Technical University of Crete, Chania, Greece. Electronic address: nicolas.kalogerakis@enveng.tuc.gr.
authors.forename: N
authors.initials: N
authors.lastname: Kalogerakis
mesh_terms: D000818:Animals; D001673:Biodegradation, Environmental; D006868:Hydrolysis; D059013:Microbial Consortia; D047328:Paracentrotus; D010578:Petroleum / Q000378:metabolism* / Q000633:toxicity; D059392:Petroleum Pollution; D018675:Toxicity Tests; D014733:Vibrio
chemical_list: D010578:Petroleum
keywords: Allochthonous degraders; Autochthonous degraders; Bioaugmentation; Bioremediation; Biostimulation; Landfarming; Petroleum