Characterization of a bifunctional strain with crude oil degradation and biosurfactant production
A biosurfactant(BS)-producing strain YY-1,which was isolated from high-salt oily wastewater,was identified as Shewanella based on morphological,physiological,biochemical characteristics and 16S rRNA gene sequences analysis.The critical micelle concentration of the BS secreted by Shewanella sp.YY-1 was 700mg/L,the surface tension was 30.76mN/m,and the BS showed good chemical stability over a wide range of salinity(10~100g/L),temperature(25~100℃)and pH(2~10).The extracted BS were identified as phospholipids according to thin-layer chromatography,fourier infrared spectroscopy and gas chromatography-mass spectrometry.The results of bioremediation of crude oil wastewater with strain Shewanella sp.YY-1 showed favourable degradation performance.The removal efficiency of short-chain alkanes(C8~C10),medium-chain alkanes(C11~C20),and long-chain alkanes(C21~C44)were 74.70%,96.68%,and 99.42%,respectively.This study could provide excellent strain resource and theoretical basis for the bioremediation of crude oil wastewater with BS-producing bacteria.