ABSTRACT
Interest and use of chemical surfactants have grown during the last decade, mainly due to their application in various process industries including food, detergent, oil recovery, and environmental bioremediation. The annual global production of synthetic surfactants was 13 million metric tons in the year 2008, and the total surfactant market is expected to generate revenues of more than USD 41 billion by 2018 (Ashby et al. 2013). However, increasing awareness about the negative environmental impact of chemical surfactants has called for the use of ecologically safe surfactants. Microbial surfactants are green amphiphilic molecules that are capable of lowering the surface and interfacial tensions of uid phases signicantly. In contrast to the chemically synthesized surfactants, biosurfactants are less toxic, highly biodegradable, and stable at extremes of pH, temperature, and salinity (Mukherjee et al. 2006). Furthermore, microbial surfactants possess diverse chemical structures that favor the use of these molecules in various elds such as energy, environment, and healthcare (Das et al. 2008a,b; Mukherjee et al. 2009; Sen 2008).
