New insights in biosurfactants research

Surfactants are molecules that are characterized by their surface-active properties but have a diverse chemical composition as was discussed in the previous chapter. Due to their tensio-active behavior, they are used in a wide variety of industrial applications, ranging from the soap and detergent industries to food, cosmetics, agriculture, oil recovery, and bioremediation. Most of the surfactants in the market are chemically synthesized but, in several cases, they are toxic and recalcitrant compounds that represent an environmental hazard, since they are mainly petroleum derived. An environmentally friendly and sustainable alternative is represented by biosurfactants (BSs) produced by microorganisms. However, BSs currently represent a small share of the market. This is mainly due to the lower production cost of chemically synthesized surfactants and to important technical challenges in the large-scale production of BS, such as foaming during the fermentation process, which is difficult to manage and causes loss of biomass from the bioreactor. In this chapter we will describe some of the recent developments in the field of BS research, discussing different perspectives and the latest research innovations coming from diverse scientific approaches, that include the description of some of the microorganisms that produce BS, metabolic engineering strategies that have been reported for increasing their production, novel strategies in fermentation and downstream processing for their production. We will also present some applications of several BS types.