Response of the bacterial community in oil-contaminated marine water to the addition of chemical and biological dispersants.
The use of dispersants in different stages of the oil production chain and for the remediation of water and soil is a well established practice. However, the choice for a chemical or biological dispersant is still a controversial subject. Chemical surfactants that persist long in the environment may pose problems of toxicity themselves; therefore, biosurfactants are considered to constitute an environmentally friendly and effective alternative. Nevertheless, the putative effects of such agents on the microbiomes of oil-contaminated and uncontaminated marine environments have not been sufficiently evaluated. Here, we studied the effects of the surfactant Ultrasperse II®and the surfactin (biosurfactant) produced by Bacillus sp. H2O-1 on the bacterial communities of marine water. Specifically, we used quantitative PCR and genetic fingerprint analyses to study the abundance and structure of the bacterial communities in marine water collected from two regions with contrasting climatic conditions. The addition of either chemical surfactant or biosurfactant influenced the structure and abundance of total and oil-degrading bacterial communities of oil-contaminated and uncontaminated marine waters. Remarkably, the bacterial communities responded similarly to the addition of oil and/or either the surfactant or the biosurfactant in both set of microcosms. After 30 days of incubation, the addition of surfactin enhanced the oil-degrading bacteria more than the chemical surfactant. However, no increase of hydrocarbon biodegradation values was observed, irrespective of the dispersant used. These data contribute to an increased understanding of the impact of novel dispersants on marine bacteriomes before commercial release into the environment.
Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
Camila Rattes de Almeida
CR
Couto
Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
Diogo de Azevedo
DA
Jurelevicius
Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
Vanessa Marques
VM
Alvarez
Microbial Ecology Department, University of Groningen, Groningen, The Netherlands.
Jan Dirk
JD
van Elsas
Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil. Electronic address: lseldin@micro.ufrj.br.
Lucy
L
Seldin
D001673:Biodegradation, Environmental; D006838:Hydrocarbons / Q000378:metabolism; D010578:Petroleum / Q000378:metabolism; D013501:Surface-Active Agents / Q000378:metabolism; D014867:Water; D014876:Water Pollution
D006838:Hydrocarbons; D010578:Petroleum; D013501:Surface-Active Agents; D014867:Water
Bacterial community; Biosurfactant; Dispersant; Oil-contaminated marine water; Surfactin; Ultrasperse II