Green Chemistry and Technology

Microbial biosurfactants are one of the most fascinating success stories in the field of green chemistry since at least four decades. Specific microorganisms are able to produce large quantities of biodegradable molecules with surface active properties. If phospholipids, lipopeptides, glycolipids and polymers are the major classes, glycolipids certainly constitute the most interesting one for the large produced amounts. Compounds like sophorolipids and rhamnolipids are now well-known and routinely employed in detergent and cosmetic formulations, for their low toxicity and high biodegradability. Despite these important achievements, many questions still lie unanswered and the potential of these molecules

is in fact largely underexploited, especially in other domains like colloid chemistry and materials science. Th is paper will illustrate the recent advances in terms of molecular developments through both chemical and genetic engineering tools, thus expanding the portfolio of existing molecules. It will also discuss the most recent understanding between selected molecular structures and their corresponding physicochemical properties. It will conclude on the potential development of biosurfactantbased soft materials, including hydrogels, tough foams and emulsions.