Optimization study of enzymatic synthesis of oleyl oleate, an analog of jojoba oil, by response surface methodology

✍ Scribed by G.A. Macedo; D.B. Lopes

• Publisher: Elsevier
• Year: 2009
• Tongue: English
• Weight: 70 KB
• Volume: 25
• Category: Article
• ISSN: 1871-6784
• DOI: 10.1016/j.nbt.2009.06.493

✦ Synopsis

Traditional liquid wax esters are derived from several natural sources such as jojoba seed (Semmondsia chinensis) and sperm whale oil. Oleyl oleate, which is an esterification product of oleic acid an oleyl alcohol, can be considered as a synthetic analog of jojoba oil. Lipase catalyzed production of oleyl oleate, was carried out using oleic acid and oleyl alcohol in the solvent-free system. Rhizopus sp. lipase was used as a biocatalyst and commercial Lipozyme TL IM ® was used to compare results. Response surface methodology based on five-level, two variable central composite rotatable design was used to evaluate the effects of important parameters on the production of oleyl oleate. Acid/alcohol molar ratio (1:0.6-1:3.4 for Rhizopus sp. and 1:1.6-1:4.4 for Lipozyme TL IM ® ) and enzyme concentration (4.2-9.8%) were chosen as process variables for the optimization. Between these parameters, acid/alcohol molar ratio has significant effects for both enzymes and enzyme quantity just for Lipozyme TL IM ® . Optimum conditions were found to be acid/alcohol molar ratio of 1:2 for Rhizopus sp. and 1:3 for Lipozyme TL IM ® , and enzyme quantity of 9.8% (w/w) in two hours of reaction time. The rate of the sterification reaction yielded 93.1% using lipase from Rhizopus sp., very close to what it is obtained using commercial Lipozyme TL IM ® that is 94.2%. The ester identity was conduced by gas chromatography-mass spectrophotometer (GC-MS) analysis.