Characterization and performance of a new lipopeptide biosurfactant producing strain Bacillus Subtilis R1-2
Authors:   1 State Key Laboratory of Bioreactor Engineering, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China 2 Daqing Huali Biotechnology Co. Ltd, Daqing 163000, China, Qi Gui-Na , Li Guo-Jun ,   1 State Key Laboratory of Bioreactor Engineering, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China 2 Daqing Huali Biotechnology Co. Ltd, Daqing 163000, China, Zhou Lei ,   1 State Key Laboratory of Bioreactor Engineering, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China 3 MOE Engineering Research Center of Microbial Enhanced Oil Recovery, East China University of Science and Technology, Shanghai 200237, China, Wu Lian-He ,   2 Daqing Huali Biotechnology Co. Ltd, Daqing 163000, China, Liu Yi-Fan ,   1 State Key Laboratory of Bioreactor Engineering, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China 3 MOE Engineering Research Center of Microbial Enhanced Oil Recovery, East China University of Science and Technology, Shanghai 200237, China, Liu Jin-Feng ,   Daqing Huali Biotechnology Co. Ltd, Daqing 163000, China, Gang Hong-Ze ,   1 State Key Laboratory of Bioreactor Engineering, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China 3 MOE Engineering Research Center of Microbial Enhanced Oil Recovery, East China University of Science and Technology, Shanghai 200237, China, Yang Shi-Zhong ,   1 State Key Laboratory of Bioreactor Engineering, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China,   3 MOE Engineering Research Center of Microbial Enhanced Oil Recovery, East China University of Science and Technology, Shanghai 200237, China, Mu Bo-Zhong ,   State Key Laboratory of Bioreactor Engineering, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China,   MOE Engineering Research Center of Microbial Enhanced Oil Recovery, East China University of Science and Technology, Shanghai 200237, China
Published: October 2024

Biosurfactants produced by native microorganisms have excellent surface activity and ideal environmental compatibility, and the mining of the biosurfactant-producing strains has become a key focus in the field of applied and environmental biotechnology. In this paper, we report a new lipopeptide-producing strain isolated from the production water of Daqing oilfield in China and identified as Bacillus Subtilis R1-2 based on 16S rRNA gene sequence analyses. A combination of ESI-MS and FT-IR analyses revealed that the strain R1-2 produced the surfactin family containing four members of the C12-surfactin, C13-surfactin, C14-surfactin and C15-surfactin, which is a representative family of the lipopeptide biosurfactants. The lipopeptide biosurfactant produced by the strain R1-2 exhibits excellent surface activity and good thermal stability over a temperature range between 20°C and 100°C and pH range between 3 and 14, and has a strong salt tolerance to NaCl concentration up to 140 g/L. In addition, the lipopeptide biosurfactant demonstrates significant properties in changing the contact angles of oil reservoir core slices from 86.2° to 39.0° and the wettability from strong oil-wet to strong water-wet, and therefore, resulted in a good oil removing ability with an efficiency of 64.84%, suggesting that the lipopeptide-producing strain R1-2 is promising in applications in environmental bioremediation and enhanced oil recovery.