title: Sophorolipids Production by Candida bombicola ATCC 22214 and its Potential Application in Microbial Enhanced Oil Recovery.
abstract: Biosurfactant production using Candida bombicola ATCC 22214, its characterization and potential applications in enhancing oil recovery were studied at laboratory scale. The seed media and the production media were standardized for optimal growth and biosurfactant production. The production media were tested with different carbon sources: glucose (2%w/v) and corn oil (10%v/v) added separately or concurrently. The samples were collected at 24 h interval up to 120 h and checked for growth (OD660), and biosurfactant production [surface tension (ST) and interfacial tension (IFT)]. The medium with both glucose and corn oil gave better biosurfactant production and reduced both ST and IFT to 28.56 + 0.42mN/m and 2.13 + 0.09mN/m, respectively within 72 h. The produced biosurfactant was quite stable at 13-15% salinity, pH range of 2-12, and at temperature up to 100°C. It also produced stable emulsions (%E24) with different hydrocarbons (pentane, hexane, heptane, tridecane, tetradecane, hexadecane, 1-methylnaphthalene, 2,2,4,4,6,8-heptamethylnonane, light and heavy crude oil). The produced biosurfactant was extracted using ethyl acetate and characterized as a mixture of sophorolipids (SPLs). The potential of SPLs in enhancing oil recovery was tested using core-flooding experiments under reservoir conditions, where additional 27.27% of residual oil (Sor) was recovered. This confirmed the potential of SPLs for applications in microbial enhanced oil recovery.
authors.affiliation: Department of Biology, College of Science, Sultan Qaboos University Muscat, Oman.
authors.forename: Abdulkadir E
authors.initials: AE
authors.lastname: Elshafie
authors.affiliation: Department of Biology, College of Science, Sultan Qaboos University Muscat, Oman ; Central Analytical and Applied Research Unit, College of Science, Sultan Qaboos University Muscat, Oman.
authors.forename: Sanket J
authors.initials: SJ
authors.lastname: Joshi
authors.affiliation: Department of Petroleum and Chemical Engineering, College of Engineering, Sultan Qaboos University Muscat, Oman.
authors.forename: Yahya M
authors.initials: YM
authors.lastname: Al-Wahaibi
authors.affiliation: Department of Petroleum and Chemical Engineering, College of Engineering, Sultan Qaboos University Muscat, Oman.
authors.forename: Ali S
authors.initials: AS
authors.lastname: Al-Bemani
authors.affiliation: Department of Biology, College of Science, Sultan Qaboos University Muscat, Oman.
authors.forename: Saif N
authors.initials: SN
authors.lastname: Al-Bahry
authors.affiliation: Department of Biology, College of Science, Sultan Qaboos University Muscat, Oman.
authors.forename: Dua'a
authors.initials: D
authors.lastname: Al-Maqbali
authors.affiliation: School of Biomedical Sciences, University of Ulster Coleraine, UK.
authors.forename: Ibrahim M
authors.initials: IM
authors.lastname: Banat
keywords: Candida bombicola; biosurfactant; core-flood experiment; microbial enhanced oil recovery; sophorolipids