Effect of unconventional carbon sources on biosurfactant production and its application in bioremediation

The potential of an alkaliphilic bacterium Klebsiella sp. strain RJ-03, to utilize different unconventional carbon sources for the production of biosurfactant was evaluated. The biosurfactant produced using corn powder, potato peel powder, Madhuca indica and sugarcane bagasse containing medium, exhibited significantly higher viscosity and maximum reduction in surface tension as compared to other substrates. Among several carbon substrates tested, production of biosurfactant was found to be the highest with corn powder (15.40 +/- 0.21 g/l) as compared to others. The comparative chemical characterization of purified biosurfactant was done using advance analytical tools such as NMR, FT-IR, SEM, GPC, MALDI TOF-TOF MS, GC-MS, TG and DSC. Analyses indicated variation in the functional groups, monosaccharide composition, molecular mass, thermostability. Higher yield with cheaper raw materials, noteworthy stress tolerance of CP-biosurfactant toward pH and salt as well as compatibility with chemical surfactants and detergents revealed its potential for commercialization and application in bioremediation. (C) 2013 Elsevier B.V. All rights reserved.