Biosurfactants: Production and Role in Synthesis of Nanoparticles for Environmental Applications

Preferred methods for nanoparticles synthesis are physical (high pressure, temperature) or chemical methods (strong oxidizing and reducing chemical agents), which are frequently plagued with issues of toxic by-products formation. Green synthesis methods employing biological agents (such as microorganisms and plants) for nanoparticles synthesis is gaining strength over the last decade. The biosynthesis of nanoparticles is an environmentally friendly alternative to chemical and physical methods, but still facing certain setbacks with respect to scale up and economics. Biosurfactants are one of such promising environment friendly amphiphilic biomolecules, which have unique properties, such as the ability to reduce the surface activity at the interfaces of different polarity, altering the surface wettability, making emulsions (oil-in-water or water-in-oil). Biosurfactant have recently been reported for the synthesis of nanoparticles of different metals and metal oxides, having unique features of reducing surface activity at different interfaces, emulsifying properties, and the ability to act as capping, reducing, and stabilizing agent, making them a promising contender in green nanoparticles synthesis process. Thus synthesised biosurfactant based nanoparticles could be used for several environmental applications, such as treatment of volatile organic compounds, photocatalytic degradation of organic (azo) dyes, removal of (poly)chlorinated organic pollutants and heavy metals from soil and water, to list a few potential applications.