Chapter 14 - Routing microbial biosurfactants to agriculture for revitalization of soil and plant growth

Abstract

Surfactants are amphiphilic substances that decrease the interfacial tension. Presently, the major proportion of surfactants holding the market is largely dominated by the surfactants of chemical origin. The surfactants of chemical origin produce several negative impacts on the environment, for instance, their toxicity towards the lower form of life, persistence in the environment for a longer time, and soil pollution. The biobased surfactants of microbial origin are the secondary metabolites of definite microorganisms that represent the potential substitute of chemical surfactants and owe the potential to replace chemical surfactants in the different agricultural applications. The inherent low CMC value of biosurfactants further warrants their application in agricultural systems. In addition to it, several unique traits possessed by biosurfactants, for instance, the enhanced solubilization triggered by microbial degradation of recalcitrant pesticides and hydrocarbons prove their superiority over chemical surfactants. Additionally, the biosurfactants are also known to enhance the seed germination process in the normal as well as heavy metal and hydrocarbon contaminated soils. They are also deliberated to aid plant growth by enhancing the availability of several key micronutrients. Furthermore, the antimicrobial activities of several biosurfactants against different plant pathogenic microbes project their usage as persuasive biocontrol agents. The present chapter summarizes the role of biosurfactants as a potential alternative to chemical surfactants along with the exploration of their different applications in agricultural systems.