title: Characterization of a blend-biosurfactant of glycolipid and lipopeptide produced by Bacillus subtilis TU2 isolated from underground oil-extraction wastewater.
abstract: Biosurfactants have versatile properties and potential industrial applications. A new producer, B. subtilis TU2, was isolated from the underground oil-extraction wastewater of Shengli Oilfield, China. Preliminary flask culture showed that the titer of biosurfactant obtained from the broth of TU2 was ~1.5 g/l at 48 h (718 mg/l after purification), with a reduced surface tension of 32.5 mN/m. The critical micelle concentration was measured as 50 mg/l and the surface tension maintained stability in solution with 50 g/l NaCl and 16 g/l CaCl(2) after 5 days of incubation at 70°C. FT-IR spectra exhibited the structure information of both glycolipid and lipopeptide. MALDI-TOF-MS analyses confirmed that the biosurfactant produced by B. subtilis TU2 was a blend of glycolipid and lipopeptide, including rhamnolipid, surfactin, and fengycin. The blended biosurfactant showed 86% of oil-washing efficiency and fine emulsification activity on crude oil, suggesting its potential application in enhanced oil recovery.
authors: Department of Chemical Engineering, Tsinghua University, Beijing 100084, China.
authors: Fangyu
authors: F
authors: Cheng
authors: Cheng
authors: C
authors: Tang
authors: Huan
authors: H
authors: Yang
authors: Huimin
authors: H
authors: Yu
authors: Yu
authors: Y
authors: Chen
authors: Zhongyao
authors: Z
authors: Shen
mesh_terms: D001412:Bacillus subtilis / Q000302:isolation & purification / Q000378:metabolism*; D015373:Bacterial Typing Techniques; D002681:China; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D006017:Glycolipids / Q000737:chemistry* / Q000378:metabolism*; D060587:Groundwater / Q000382:microbiology; D055666:Lipopeptides / Q000737:chemistry* / Q000378:metabolism*; D008969:Molecular Sequence Data; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D017550:Spectroscopy, Fourier Transform Infrared; D013501:Surface-Active Agents / Q000737:chemistry* / Q000378:metabolism*; D062065:Wastewater / Q000382:microbiology
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D006017:Glycolipids; D055666:Lipopeptides; D012336:RNA, Ribosomal, 16S; D013501:Surface-Active Agents; D062065:Wastewater