Sustainable production of biosurfactants and biofuel: Chemistry in benefit of Medicine and enviroment

Abstract

Surfactins, biosurfactants with high surface activity and both medical and environmental applications are produced by Bacillus subtilis. Its production is very expensive and, despite of some residues generated from biosurfactant production, such as microbial biomass, they are rarely used for other purposes. The alternatives are: (i) to use cheaper substrates for growth and maintenance of B. subtilis, (ii) to add value to extracts and/or biomass, (iii) synthesize them. Being a peptide, surfactin can be obtained by solid-phase synthesis (SPPS). However, there are a few reports describing the synthesis of surfactins by SPPS, both of them employing large amounts of volatile organic solvents, which cause environmental impact. The peptide portion of surfactins contains 7 amino acid residues (LLDLLDL configuration) linked to a beta-hydroxy fatty acid (13 to 15 carbons), creating a loop that joins the carboxyl end of the peptide and the 3-hydroxy fatty acid. Considering that the presence of D-amino acids in their structures is relevant for biological activity but not to the surfactant properties, and knowing that surfactins linear derivatives exhibit low hemolytic activity, the goals of this project are: (i) to establish an alternative for the production of linear surfactin lipopeptides: chemical synthesis, (ii) to evaluate the application of the produced lipopeptides (both natural and synthetic), such as growth inhibition and prevention of microorganisms adhesion (iii) to study a strategy capable of valorizing the biomass that would be discarded: enzymatic conversion of bacterial biomass for the production of biodiesel using natural or artificial lipases as catalysts.