rd
23 Congress of the International Union for Biochemistry and Molecular Biology
th
44 Annual Meeting of the Brazilian Society for Biochemistry and Molecular Biology
th
th
Foz do Iguaçu, PR, Brazil, August 24 to 28 , 2015
BIOPROSPECTION
OF
FOR BIOREMEDIATION.
OIL
DEGRADING
MICROORGANISMS
Napp, A. P. 1,2, Allebrandt, S. R. 1,2, Vainstein, M. H. 1*
1
Departamento de Biologia Molecular and Biotecnologia, Universidade Federal do
Rio Grande do Sul, Rio Grande do Sul, Porto Alegre, Brasil; 2 Bioplus
Desenvolvimento Biotecnológico Ltda., Rio Grande do Sul, Porto Alegre, Brasil.
The growing petroleum derivatives demand has increased the exploration
and production of these compounds. Consequently, the number of accidents
involving oil spills has risen, causing serious environmental problems. Recently,
the use of oil degrading microorganisms in contaminated areas appears as a
sustainable alternative to minimize these environmental impacts. Therefore, in this
work we isolated microorganisms able to grow in aquatic environments containing
oil and analyzed the potential oil degradation mediated by these microorganisms.
The isolated were submitted to a pre-test with TTC redox indicator and selected
for further subsequent tests. After, it was performed a visual evaluation of the
degradation and solubilization of hydrocarbons by selected microorganisms in
media containing (i) bioaugmentation treatment (ii) biostimulation treatment and
(iii) both biostimulation and bioaugmentation treatment. Also, we evaluated the
capability of biosurfactants production. The molecular identification was performed
by sequencing of the 16S and 26S conserved regions of ribosomal DNA. Firstly,
19 microorganisms were isolated from two batches of previously contaminated soil
with a high concentration of crude oil. The previous analysis of isolates with TTC
selected 3 bacteria (BPH 1.4, BPH 1.5 and BPH 1.14) and 3 yeasts (BPH 2.1,
BPH 2.2 and BPH 2.3). All isolates showed IE24%>38% and IE24%>39% in
presence and absence of microbial cells, respectively. Similarly, all organisms
were able to reduce the surface tension of the utilized medias. The bacteria
isolates BPH 1.4, BPH 1.5 and the yeast isolate BPH 2.2 were able to produce
biosurfactants as ramnolipids. Our results show that the isolated microorganisms
seem to be promising in the degradation of petroleum hydrocarbons, but further
studies are essential in order to develop an effective formulation that could be
employed directly in the oil-contaminated environments.
Keywords: Bioremediation; oil degrading; biosurfactants production.
Brazilian Society for Biochemistry and
Molecular Biology (SBBq)