Enhanced sophorolipid derivatives

A method for producing a cationic sophorolipid (SLP) derivative, the method comprising

• a) producing a linear SLP molecule having an 18-carbon fatty acid moiety with a single unsaturated bond at the ninth carbon, and one of b), c), or d):
• b) subjecting the linear SLP molecule of a) to ozonolysis to oxidize the fatty acid moiety to an ozonide, and reducing the SLP-ozonide with a reducing agent to produce an aqueous crude linear SLP aldehyde;
• c) subjecting the linear SLP molecule of a) to a process comprising:
• 1) Epoxidizing the alkene group of the SLP;
• 2) Opening the epoxide to form a vicinal diol;
• and
• 3) Oxidatively cleaving the vicinal diol to produce an aqueous crude linear SLP aldehyde;
• or
• d) converting the free carboxylic acid group of the linear SLP molecule of a) into a methyl ester using alkaline hydrolysis, and applying DIBAL-H as a reducing agent to convert the methyl ester into an aldehyde functional group, thereby producing a crude linear SLP aldehyde;
• and
• e) after one of b), c), or d), extracting the linear SLP aldehyde from the aqueous crude linear SLP aldehyde and subjecting the extracted linear SLP aldehyde to reductive amination, thereby producing a SLP scaffold covalently linked to a primary amine, said linked SLP scaffold and primary amine comprising the cationic SLP derivative, wherein the cationic SLP derivative is present in a reductive amination reaction mixture, and purifying the cationic SLP derivative from the reductive amination mixture wherein the reductive amination of e) comprises introducing a peptide ethyl ester to the linear SLP aldehyde in the presence of a reducing agent and weak organic acid, and wherein the peptide ethyl ester comprises Arg-Arg-Arg-Arg, Gly-Gly-Arg-Arg, Gly-Arg-Gly-Arg, or Gly-Arg-Arg-Arg.