The catalytic activity of lipases toward hydroxy fatty acids—A review

Abstract

Hydroxy fatty acids, derived from several natural and synthetic sources, have many applications. Lipases have been employed to catalyze reactions involving hydroxy acids to narrowly shape the product distribution via their regio-and stereoselectivities. This manuscript reviews the action of lipase on hydroxy acids and their derivatives. The formation of estolides or lactones by lipase-catalyzed reactions depends strongly on the position of the hydroxyl moiety on the hydroxy acyl group and slightly on the hydroxy acid chainlength and concentration. Pseudomonas sp. and porcine pancreatic lipases are the most useful for catalyzing formation of optically pure lactones, while lipases lacking positional selectivity catalyze estolide formation best. The product distribution of lipase-catalyzed esterification between hydroxy-and nonhydroxy-acyl groups is strongly dependent on the lipase type. Lipase-catalyzed reactions between hydroxy acids and alcohols yield hydroxy esters, not estolides, as the major product. JAOCS 73, 543-549 (I 996).

Chemistry and physical properties of estolides

“…Subsequent conversion to oleyl and decyl esters was readily accomplished and melting points of -19 o C was reported for both of these derivatives along with viscosity indices of 150-302. Hayes went on to write a review for the use of lipase catalysis (Hayes 1996) with a few examples of estolides formed from lesquerella and castor fatty acids. Kiatsimkul et al, (2008) used C. rugosa or C. antartica lipases to synthesize homo-oligomeric estolides of ricinoleic acid both under vacuum and atmospheric pressures at 60 o C. The reaction required 5 days to yield ~50% estolide which consisted of dimmers and trimers.…”

Natural estolides produced by Pseudomonas sp. 42A2 grown on oleic acid: Production and characterization

“…Recently, lipases isolated from Candida rugosa, Rhizomucor miehei, Pseudomonas, and Alcaligenes were found suitable for estolide synthesis in vitro using δ-lactones or hydroxy FA of various chain lengths. The largest monomers described as estolide components have been ricinoleic acid and 12-hydroxystearic acid (7,8).…”

Enzymes as biocatalysts in the modification of natural lipids

“…Bornscheuer 57 has described the lipase-catalysed synthesis of monoacylglycerols, and the ability of lipases to convert hydroxy acids to lactones and estolides is considered by Hayes. 150 Gandhi 151 has produced a useful review on lipase applications covering both hydrolysis and ester synthesis. Other reviews devoted to lipases are by Quinlan and Moore 116 and by Rosendaal and Macrae.…”