Identification of Bacillus subtilis THY-7 and high titer optimization for the blend-biosurfactant of lipopeptide and glycolipid.
- Author:
Hao LIU
;
Huan YANG
;
Xue LI
;
Xu LI
;
Mian DUANMU
;
Huimin YU
- Publication Type:Journal Article
- MeSH:
Bacillus subtilis;
growth & development;
isolation & purification;
metabolism;
Chromatography, High Pressure Liquid;
Culture Media;
Glycolipids;
biosynthesis;
Industrial Microbiology;
Lipopeptides;
biosynthesis;
Surface-Active Agents;
metabolism
- From:
Chinese Journal of Biotechnology
2013;29(12):1870-1874
- CountryChina
- Language:Chinese
-
Abstract:
Biosurfactants (BSs) are highlighted owing to their multiple advantages in diverse applications. To screen a superior strain that producing a blend-biosurfactant of lipopeptide and glycolipid, the hemolytic activity assay on blood agar plates, the modified oil-red spreading test and MALDI-TOF Mass Spectrometry identification of the purified products was carried out. Bacillus subtilis THY-7 was selected and its principal products were surfactin and dirhamnolipid. The medium component and culture conditions of THY-7 were optimized by both single factor and orthogonal experiments. After 48 h optimal batch culture in flask, the cell density (OD600) was 37.0 and the product titer was 2.4 g/L, which was 3.4 folds and 3.1 folds of that under original condition, respectively. A fed-batch culture in a 5 L fermentor was further performed coupling with in situ recovery of foam, in which the titer of blend-BS increased to 4.5 g/L at 25 h. Quantification by HPLC and anthrone colorimetry revealed that surfactin and dirhamnolipid accounted for 74% and 22% of the blend-BS, respectively.
