Microbial induced lipoprotein biosurfactant from slaughterhouse lipid waste and its application to the removal of metal ions from aqueous solution

This study aims at demonstrating the production of lipoprotein biosurfactant from Pseudomonas gessardii using goat tallow, a slaughterhouse lipid waste, as the substrate and its application to the removal of metal ions from aqueous solution. The maximum bio-transformation of goat tallow into biosurfactant occurred at 48 h. The mass of the lipoprotein biosurfactant produced was 2.03 g/g of goat tallow. The biosurfactant was clearly characterized by surface tension, critical micelle concentration, emulsification index and molecular weight. The amino acid and fatty acid moieties of the biosurfactant were determined using High performance liquid chromatography (HPLC) and Gas chromatography (GC). The thermal behavior studies were evaluated using Thermo gravimetric (TG) and Differential scanning calorimetry (DSC) analysis. The lipoprotein biosurfactant was loaded onto the mesoporous activated carbon (MAC) for the sequestering of metal ions from the aqueous solution. The biosurfactant exhibited a removal efficiency for metal ions from aqueous solution in the order Cr3+ > Ca2+ > Cu2+ > Fe2+. The morphological observations and functional groups of the lipoprotein biosurfactant and that of the lipoprotein biosurfactant bound metal ions were determined using scanning electron micrograph (SEM) images and Fourier transform infrared (FT-IR) spectroscopy, respectively. This is the first report on the production of lipoprotein biosurfactant by P. gessardii using goat tallow as the substrate to sequester the metal ions from the aqueous solution.