Biodegradation of a Bioemulsificant Exopolysaccharide (EPS2003) by Marine Bacteria

Abstract

The aim of the study is to analyze the biodegradation capacity of a biosurfactant exopolysaccharide (EPS 2003 ) by heterotrophic marine bacterial strains. During the initial screening performed in two sites located at the harbor of Messina for analyzing the response of marine bacterial population with the presence of biosurfactant EPS 2003 , ten bacterial strains capable to degrade this substance were isolated. Between the bacterial strains isolated, two representative bacterial strains, isoDES-01, clustered with Pseudoalteromonas sp. A28 (100%), and isoDES-07, closely related to Vibrio proteolyticus (98.9%), were chosen for mineralization and respirometry test, performed to evaluate biodegradability potential of EPS 2003 . Assays of bacterial growth and measure of concentration of total RNA were also performed. More than 90% of EPS 2003 was mineralized by the isoDE01 strain for biomass formation and respiration, while EPS 2003 mineralization by the isoDE-07 strain was less effective, reaching 60%. This approach combines the study of the microbial community with its functional aspects (i.e., mineralization and respirometry test) allowing a more precise assessment of biosurfactant degradation. These results enhance our knowledge of microbial ecology of EPSdegrading bacteria and the mechanisms by which this biodegradation occurs. This will prove helpful for predicting the environmental fate of these compounds and for developing practical EPS 2003 bioremediation strategies from future marine hydrocarbon pollution.

High molecular weight bioemulsifiers, main properties and potential environmental and biomedical applications

“…Thus, reduced toxicity towards synthetic surfactants recognized as highly toxic (Song et al 2012) and biodegradability makes biosurfactants more suitable for industrial and environmental applications such as bioremediation. In fact, Cappello et al (2011) recommended the biodegradability of an exopolysaccharide biosurfactant.…”

Quick stimulation of Alcanivorax sp. by bioemulsificant EPS2003 on microcosm oil spill simulation

“…Microcosm SW+OIL+EPS 2003 was also supplemented with dry EPS 2003 (45 mg L −1 ). As described (Crescenzi et al , 3003; Cappello et al , 2011 ), the molecular structure of the bioemulsificant EPS 2003 corresponds to a polysaccharidic chain with hydrophobic fatty acids substitutions of 12–18 carbon atoms length. EPS 2003 is obtained by Acinetobacter calcoaceticus CBS 962.97, a hydrocarbon-degrading bacterium isolated in laboratory.…”

Biodegradation of Marine Pollutants by Microorganisms: A Bibliometric Analysis

“…Larger squares in each row represent the largest value relative to their peers. For example, Cappello (author) mentioned more bioremediation keyword in his documents [37][38][39][40][41][42][43] , while others used the marine environment keyword more in their documents 10,39,41,42,44,[45][46][47][48][49][50][51][52][53][54][55] .…”