Production, characterization, and antioxidant activities of bacterial exopolysaccharides extracted from petroleum oil water

Mohamed, Sahar S.; Selim, Manal S.; Mahmoud, Manal G.; Ibrahim, Abeer Y.; Ghazy, Eman A.

doi:10.4103/epj.epj_36_18

Production, characterization, and antioxidant activities of bacterial exopolysaccharides extracted from petroleum oil water

Authors

Abstract

Backgroundand objective
There are large quantities of water produced during the extraction of petroleum oil called ‘produced water’. The aim of this research is to isolate and identify bacteria produced exopolysaccharides (EPSs) present in this water and to evaluate their antioxidant activities as medicinal value.
Materials and methods
First isolation of Fe, Mn, and biofilm bacteria, next production of of EPSs, then morphological, physiological, and molecular characterization of isolates produced EPSs. Finally, study the characters of EPSs chemically and evaluate the antioxidant activity of EPSs by DPPH (1, 1-diphenyl-2-picrylhydrazyl) radical-scavenging model, reducing power, and by superoxide anion-scavenging activity.
Results and conclusion
Three bacteria were isolated from water of petroleum oil (produced water). These isolates produced water-soluble EPSs called Fe, Mn, and BF-EPSs and the highest production were 4.5, 7.5, and 5 g/l, respectively. The isolates were identified as SMM1, SMM2, and SMM3. Results showed that the three EPSs were acidic with different compositions of monosaccharide and different molar ratio. Uronic acid and SO were estimated. EPSs scavenged superoxide radical (O), DPPH radicals, and reducing power property. Fe-EPS was the most effective one in scavenging the superoxide radical and DPPH radicals while the highest reductant is BF-EPS. The obtained results demonstrated that all EPSs that have strong antioxidant activity can be used in medicinal and nutritional applications related to reduction of oxidative stress.

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