Abstract

Biosurfactant Production and Potential Correlation with Esterase Activity

Kamaljeet Kaur Sekhon, Sunil Khanna and Swaranjit Singh Cameotra

Biosurfactants (microbial surfactants) are surface active compounds produced extracellularly or as part of the cell membrane by several bacterial and fungal species. They have the unique property of reducing the surface and interfacial tension of liquids. Biosurfactants have applications in the field of agriculture, petroleum, microbial enhanced oil recovery, biomedical sciences, cosmetics, food processing and pharmaceuticals. The global biosurfactants market has grown gradually. Regardless of their greater biodegradability and reduced toxicity, cost competitiveness still remains the major concern for biosurfactant production. However, recombinant or metabolically engineered hyper producing strains combined with optimized cultivation conditions have made it possible for many companies to reap the benefits of ‘green’ biosurfactant technology. Simultaneously, biosurfactants and bioemulsifiers showing esterase activities and having potential applications are reported to form stable oil-water emulsions with hydrophobic substrates such as hexadecane and polyaromatic hydrocarbons. Biosurfactant production and release of esterases by the microbial cells is shown to be synchronized and symbiotically beneficial in some species. Several bacterial biosurfactant and esterase genes have been identified, cloned and expressed for their enhanced production. This review article emphasizes on the present worldwide scenario of biosurfactant production, correlation between biosurfactant production and esterase activity, recent developments in this line of research and future prospects.