Enzymatic enrichment of arachidonic acid from Mortierella single-cell oil

• Published in: Journal of the American Oil Chemists' Society 1998-09, Vol.75 (9), p.1213-1217
• Main Authors: Shimada, Y. (Osaka Municipal Technical Research Institute, Osaka, Japan.), Sugihara, A, Minamigawa, Y, Higashiyama, K, Akimoto, K, Fujikawa, S, Komemushi, S, Tominaga, Y
• Format: Article
• Language: English
• Subjects: Adducts; ARACHIDONIC ACID; Bioconversions. Hemisynthesis; Biological and medical sciences; Biotechnology; Candida; Candida rugosa; Dodecanol; enrichment; Esterification; Fatty acids; Fish oils; Fundamental and applied biological sciences. Psychology; Hexanes; Hydrolysis; lauryl alcohol; Lipase; Methods. Procedures. Technologies; MICROORGANISMS; Mixtures; Mortierella; n-Hexane; Oil; Pseudomonas; Pseudomonas sp. lipase; Recovery; Rhizopus delemar lipase; selective esterification; Stirring; Urea; urea adduct
• ISSN: 0003-021X; 1558-9331
• DOI: 10.1007/s11746-998-0137-1

An attempt was made to enrich arachidonic acid (AA) from Mortierella single‐cell oil, which had an AA content of 25%. The first step involved the hydrolysis of the oil with Pseudomonas sp. lipase. A mixture of 2.5 g oil, 2.5 g water, and 4000 units (U) Pseudomonas lipase was incubated at 40°C for 40 h with stirring at 500 rpm. The hydrolysis was 90% complete after 40 h, and the resulting free fatty acids (FFA) were extracted with n‐hexane (AA content, 25%; recovery of AA, 91%). The second step involved the selective esterification of the fatty acids with lauryl alcohol and Candida rugosa lipase. A mixture of 3.5 g fatty acids/lauryl alcohol (1:1, mol/mol), 1.5 g water, and 1000 U Candida lipase was incubated at 30°C for 16 h with stirring at 500 rpm. Under these conditions, 55% of the fatty acids were esterified, and the AA content in the FFA fraction was raised to 51% with a 92% yield. The long‐chain saturated fatty acids in the FFA fraction were eliminated as urea adducts. This procedure raised the AA content to 63%. To further elevate the AA content, the fatty acids were esterified again in the same manner with Candida lipase. The repeated esterification raised the AA content to 75% with a recovery of 71% of its initial content.