The biosurfactant of R. ruber Z25 showed a perfect emulsification activity and was able to lower the interfacial tension to approximately 1.0 mN/m and achieved a
CMC value of 57 mg/L. The biodegradation experiments of the crude oil by the strain Z25 under aerobic
and anaerobic conditions exhibited positive effects in improving the physical properties of the crude oil,
including mobility enhancement, cloud point reduction and wax degradation. Waterflooding experiments
were done to investigate the MEOR potential of the strain and varied oil recovery efficiencies from 8.88% to
25.78% were achieved. The main MEOR mechanisms of the strain Z25 included hydrocarbon degradation,
improvement of oil mobility, wettability alteration and selective plugging. These results revealed that strain
Z25 exhibited a tremendous potential for MEOR application