Production and properties of 7,10,12-trihydroxy-8(E)-octadecenoic acid from ricinoleic acid conversion byPseudomonas aeruginosa

Production of long-chain hydroxy fatty acids by microbial conversion

Hydroxy fatty acids (HFAs) are very important chemicals for versatile applications in biodegradable polymer materials and cosmetic and pharmaceutical industries. They are difficult to be synthesized via chemical routes due to the inertness of the fatty acyl chain. In contrast, these fatty acids make up a major class of natural products widespread among bacteria, yeasts, and fungi. A number of microorganisms capable of producing HFAs from fatty acids or vegetable oils have been reported. Therefore, HFAs could be produced by biotechnological strategies, especially by microbial conversion processes. Microorganisms could oxidize fatty acids either at the terminal carbon or inside the acyl chain to produce various HFAs, including α-HFAs, β-HFAs, mid-position HFAs, ω-HFAs, di-HFAs, and tri-HFAs. The enzymes and their encoded genes responsible for the hydroxylation of the carbon chain have been identified and characterized during the past few years. The involved microbes and catalytic mechanisms for the production of different types of HFAs are systematically demonstrated in this review. It provides a better view of HFA biosynthesis and lays the foundation for further industrial production.

Characterization of fatty amides produced by lipase-catalyzed amidation of multi-hydroxylated fatty acids

Novel multi-hydroxylated primary fatty amides produced by direct amidation of 7,10-dihydroxy-8(E)-octadecenoic acid and 7,10,12-trihydroxy-8(E)-octadecenoic acid were characterized by GC-MS and NMR. The amidation reactions were catalyzed by immobilized Pseudozyma (Candida) antarctica lipase B (Novozym 435) in organic solvent with ammonium carbamate. The mass spectra of the underivatized products exhibited characteristic primary amide peaks at m/z 59 and m/z 72 that differed in peak intensities. Other peaks present were consistent with cleavage next to the hydroxyl groups. The mass spectra of the silylated amidation products showed the correct molecular weight and the typical fragmentation pattern of silylated hydroxy compounds. The mass spectra, together with proton and 13C NMR data, suggest that the products of lipase-catalyzed direct amidation of 7,10-dihydroxy-8(E)-octadecenoic acid and 7,10,12-trihydroxy-8(E)-octadecenoic acid are, 7,10-dihydroxy-8(E)-octadecenamide and 7,10,12-trihydroxy-8(E)-octadecenamide acid, respectively. Amidation of multi-hydroxylated fatty acids had increased the melting point, but reduced the surface active property of the resulting primary amides.