Fatty ethyl ricinoleate

Other Cig-fatty acids have also a high potential in hydroformylation, such as ricinoleic acid, which contains an additional hydroxy group at position 12 of the fatty carbon chain and which is not food relevant [26], The hydroformylation of ethyl ricinoleate, derived from castor oil, shows selectivity for cyclization of the carbon chain because of the reaction of the hydroxyl group with the formyl group (Scheme 8). 

A commercial castor oil (Delaware-Brazil) was used as purchased without any pretreatment. The fatty acid composition was determined using a gas chromatograph (HP 5890) with a flame ionization detector. The following instrumentation and conditions were used H2 as carrier gas, modified polyethylene glycol column (FFAP 2 - 25 m x 0.20 mm id x 0.30-mm film), column temperature of 180-210°C (2°C/min), injector temperature of 250°C, and detector temperature of 280°C. Using this procedure, the approximate fatty acid composition in castor oil is 92 wt% ricinoleic acid and 8 wt% other acids. Ethyl alcohol (95 v/v%) (Merck) and n-hexane PA (Merck) were used as substrate and solvent, respectively. 

The stereoisomeric pairs of ricinoleate, methyl isoricinoleate, and methyl esters of three additional bis-homoallylic hydroxy fatty acids were separated as their a-naphthylethyl isocyanate derivatives [696]. A silica column and a 95/5/1 hexane/ ethyl acetate/THF mobile phase generated the separation. Elution was generally complete in <30 min and resolution was excellent in all cases. 

The synthesis of y-DL is the most prominent example for the microbial production of fragrance lactones. Nevertheless, the biotransformation route via P-oxidation and lactonization (Fig. 1) in yeast can be applied for the production of several lactones provided that a suitable hydroxy fatty acid as starting material is available. For example, ricinoleic acid, the starting compound for the production of y-DL, can be isolated in large quantities from castor oil. However, other hydroxy fatty acids are more difficult to obtain. For instance, researchers from Takasago International Corporation reported the conversion of 11-hydroxy palmitic acid ethyl ester to 8-decalactone by the yeast Candida sorbophila (Mitsuhashi and limori 2004). 0.13 g substrate in 30 itiL culture medium yielded 0.019 g 8-decalactone in 96 % ee optical purity after 11 days. 

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