Biosurfactants from Yeasts

Biosurfactants are surface active compounds derived from living organisms, mainly microorganisms. Almost all surfactants currently in use are chemically derived from petroleum. However, in recent years, the interest in chemical surfactants has been substituted by an increase in the use of microbial surfactants. Compared with chemical surfactants, biosurfactants have more advantages, for example, their lower toxicity, higher biodegradability and better environmental compatibility. Most known biosurfactants are of bacterial origin, and only a few biosurfactants come from yeasts and molds. Biosurfactants have not yet been employed extensively in industry because of the relatively high production and recovery costs involved. To reduce the costs of biosurfactant production, it is necessary to select microorganisms capable of high-yield biosurfactant production. This review describes screening of biosurfactant producing-yeasts, the estimation of biosurfactant activity as well as medium components which affect biosurfactant production. The characterization of biosurfactants from yeasts is also discussed.