Abstract
Biosurfactants (BS) produced by various microorganisms show unique properties (e.g. mild production conditions, lower toxicity, and environmental compatibility) compared to their chemical counterparts. The numerous advantages of BS have prompted applications not only in the food, cosmetic, and pharmaceutical industries but in energy and environmental technologies as well. A yeast strain of Candida antarctica was found to produce a large amount of mannosylerythritol lipids (MEL) from different vegetable oils or hydrocarbons. MEL exhibited not only excellent surface-active properties but also versatile biochemical actions, including antimicrobial activity and differentiation-inducing activity against human leukemia cells. Interestingly, MEL showed a remarkable anti-agglomeration effect on ice particles in an ice-water slurry system used for cold thermal storage, and attained a high ice-packing factor to improve the system efficiency and environmental load. MEL also displayed high binding affinity and capacity toward human imuunoglobulin G on polymer beads, indicating a great potential as a new affinity ligand for the protein. In addition, MEL showed excellent self-assembling properties to form giant liposomes. More significantly, the cationic liposomes bearing MEL increased dramatically the efficiency of gene transfection into mammalian cells. The yeast BS should thus be a new nano-biomaterial, and broaden their applications in various advanced technologies.
