ABSTRACT:In this study, the production and characterization of a biosurfactant from yeast Wickerhamomyces anomalus strain PY189 was carried out. The highest efficiency for biosurfactant production was found when the organism was grown in a medium containing 4% (v/v) soya bean oil and 0.4% (w/v) NaNO 3 at 30°C and pH 5.5 for 7 days. After 7 days of cultivation, W. anomalus PY189 was able to produce up to 0.57 g/l of biosurfactant as ethyl acetate extracts. The culture supernatant was able to reduce the surface tension of the culture broth from 42.5 mN/m to 36.5 mN/m with a critical micelle concentration of 204 mg/l. The crude extract of biosurfactants was then applied to the encapsulation of lemongrass oil. Emulsions of lemongrass oil in 20 mg/dl maltodextrin solution (oil:maltodextrin solution ratios of 0.2:1, 0.15:1, and 0.1:1) containing 0.8% and 1% (w/v) crude biosurfactant extract were stable for at least 24 h and had an average oil droplet size of less than 10 µm. Lemongrass oil microcapsules were later produced using a spray drying technique. This microcapsule exhibited microbial growth inhibition activity against E. coli, S. aureus, and Salmonella at 5% (w/v) concentration.