Microcosms experiments were carried out to evaluate the effect of bioemulsificant exopolysaccharide
(EPS2003) on microbial community dynamics. An experimental seawater microcosm, supplemented with
crude oil and EPS2003 (SW + OIL + EPS2003), was monitored for 15 days and compared to control
microcosm (only oil-polluted seawater, SW + OIL). Determination of bacterial abundance, heterotrophic
cultivable and hydrocarbon-degrading bacteria were carried out during all experimentation period.
The microbial community dynamic was monitored by isolation of total RNA, RT-PCR amplification of
16S rRNA, cloning and sequencing. Oil degradation was monitored by GC–MS analysis. Bioemulsificant
addition stimulated an increase of the total bacterial abundance, change in the community structure
and activity. The bioemulsificant also increased of 5 times the oil biodegradation rate.
The data obtained from microcosm experiment indicated that EPS2003 could be used for the dispersion
of oil slicks and could stimulate the selection of marine hydrocarbon degraders thus increasing bioremediation
process.
