Synergistic effect of crude oil plus dispersant on bacterial community in a louisiana salt marsh sediment

Abstract

A combined effect of crude oil plus dispersant (Corexit 9500A) significantly altered indigenous bacterial communities in a Louisiana salt marsh sediment after 30 days of incubation; the crude oil and/or Corexit 9500A treatments triggered shifts in bacterial communities and the shifted bacterial structure by crude oil plus Corexit 9500A was considerably different from those by either crude oil or Corexit 9500A. However, the synergistic effect of crude oil plus Corexit 9500A was not observed after 7 days of incubation; the bacterial community was slightly shifted by Corexit 9500A and the crude oil did not trigger any bacterial community shift after 7 days of incubation. DNA sequencing data indicated that Chromobacterium species was enriched in the Corexit 9500A microcosms after 7 days of incubation, while Pseudomonas, Advenella, Acidocella and Dyella spp. were enriched after 30 days of incubation. Parvibaculum was a dominant species in the crude oil microcosms after 30 days of incubation. Rhodanobacter, Dyella and Frateuria spp. were dominant in crude oil plus Corexit 9500A microcosms after 30 days of incubation. Our data show that the effect of crude oil plus Corexit 9500A on bacterial community is synergistic, and thus the dispersant effect should be considered with the spilled oil to correctly evaluate the environmental impact.

Toxicity assessment of five emerging pollutants, alone and in binary or ternary mixtures, towards three aquatic organisms

“…Recent data reported that in vivo and chronic toxicity of pharmaceutical mixtures (10 most detected active pharmaceutical ingredients in the Tama river, Japan) may also deviate from concentration addition and/or independent action to produce synergistic effects (Watanabe et al 2016). Numerous other examples of synergism are documented in the literature for mixtures of botanical pesticides, refine petroleum products, crude oil plus dispersants, or trace metals (e.g., Otitoloju 2003;Chukwuand and Okhumale 2009;Al-Jawasim et al 2015;Ekpendu et al 2016). Cleuvers (2003) also reported that combinations of various pharmaceuticals revealed stronger effects than expected from the effects measured singly.…”

Insights into Bacterial Community Involved in Bioremediation of Aged Oil-Contaminated Soil in Arid Environment

“… 27 , 77 This genus was enriched in microcosms from Louisiana salt marsh sediment treated with crude oil. 78 It was also identified among a PAHs-degrading consortium isolated from deep-sea water and marine sediments of the Indian Ocean. 79 Members of the Sphingomonas genus are often isolated from petroleum-contaminated soils.…”

Autochthonous Bioaugmentation-Modified Bacterial Diversity of Phenanthrene Degraders in PAH-Contaminated Wastewater as Revealed by DNA-Stable Isotope Probing

“…Among them, Rhodanobacter spp. are dominant in crude oil plus dispersant and rhizospheres of maize cultivars, , and Burkholderia and unclassified phylotypes within the family Xanthomonadaceae , such as Stenotrophomonas , are the dominant genera of PAH degraders with high metabolic activities in PAH-contaminated soils and sediments. , However, there was no previous evidence directly linking the above activated or abundant bacteria (except Xanthomonadaceae and Burkholderia ) to PHE degradation. They might play important roles in stabilizing the microbial community or degrading other organic pollutants in PAH-contaminated wastewater …”