Fig 1.
Biosurfactant screening assays: A. Drop collapse assay on glass slide, B. Oil spreading assay, C. Microplate assay, D. Emulsion index assay, E. Microscopic image of the emulsion formed by cell free supernatant of Gordonia sp. IITR100. (Left panel) 10% SDS (Middle panel) water, and (Right panel) cell free extract of Gordonia sp. IITR100.
Fig 2.
Emulsion stability studies: Effect of temperature (A), pH (B) and salt concentration (C) on emulsion stability. Statistical analysis of the results was performed using single factor ANOVA and p-values for temperature, pH and salt concentration profiles < 0.0001.
Fig 3.
Effect of temperature, pH and salt concentration on the microstructure of emulsion.
Fig 4.
Critical micelle concentration of the biosurfactant.
Fig 5.
Biosurfactant production in a 5 L bioreactor.
Fig 6.
TLC characterization of biosurfactant.
Left panel: Crude biosurfactant (A) stained with iodine (B) stained with ninhydrin (C) stained with p-anisaldehyde. Middle panel: Iodine staining for lipid detection (D) control rhamnolipid (E) crude biosurfactant (F) purified biosurfactant. Right panel: p-anisaldehyde staining for carbohydrate detection (G) control rhamnolipid (H) crude biosurfactant (I) purified biosurfactant.
Fig 7.
GC-MS spectrum of the extracted biosurfactant.
Fig 8.
GC-MS chromatogram.
Fig 9.
FTIR of biosurfactant produced by Gordonia sp. IITR 100.
Fig 10.
NMR of biosurfactant produced by Gordonia sp. IITR 100.
(A) H1 NMR (B) C13 NMR.
Fig 11.
Structure of biosurfactant produced by Gordonia sp. IITR100.
Table 1.
Comparison of biosurfactants produced by various strains of Gordonia.
Table 2.
Genes involved in biosynthesis of C18 fatty acid chain.
Table 3.
Genes involved in biosynthesis of carbohydrate moiety.
Table 4.
Genes involved in linking lipid chain to carbohydrate moiety to form glycolipid.