Extraction and characterization of a biosurfactant produced by

Biosurfactants are surface-active compounds that are capable of reducing surface tension and forming emulsions. Consequently, a significant amount of research has been conducted to identify and obtain bisourfactants, as they possess a variety of advantageous biological properties. Achromobacter is recognized as one of the genera that produces glycolipid biosurfactant. The objective of this investigation is to characterize the biosurfactants produced by Achromobacter xylosoxidans BP(1)5 by means of a multi-stage solvent extraction process. The biosurfactant was produced over a three-day incubation in minimal salt medium supplemented with glucose. After fermentation, the cell-free supernatant underwent sequential extraction with n-hexane, chloroform, and methanol. The critical micelle concentration (CMC) and stability of the biosurfactant were evaluated, and its structural characteristics were analyzed. The highest production yield of the crude biosurfactant was 23.75 g/L for methanol extraction. All extracts exhibited critical micelle concentration at 3 g/L, remained stable across diverse environmental conditions when evaluated with motor oil, and demonstrated anionic characteristics based on ion-interaction assays. FTIR analysis indicated the presence of sugar moieties and functional groups consistent with glycolipid biosurfactants. These findings highlight A. xylosoxidans BP(1)5 as a promising alternative biosurfactant source and demonstrate the multistage solvent extraction strategy for enhancing its recovery.