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Lipase-mediated transesterification of soybean oil with a blending alcohol consisting of methanol and 1-butanol for synthesis of fatty acid esters was carried out. Lipase from Thermomyces lanuginosa (Lipozyme TL IM) was used as a biocatalyst. The lipase was purchased from Novozymes (Seoul, Republic of Korea). The effects of the molar proportions of methanol and 1-butanol in the blending alcohol, reaction temperature, enzyme loading and water content were investigated, for reaction optimization. The relative consuming rates of methanol and 1-butanol during the reaction were also explored. Among seven different ratios of alcohol blends employed in this study, that containing 80 mol% methanol gave the highest yield of fatty acid esters. Optimum reaction temperature, enzyme loading, and water content were 30 °C, 15% (based on the substrate weight), and 0.3% (based on the substrate weight), respectively. Water influenced significantly the reaction rate and yield. On the transesterification, the degree of reaction of methanol was higher than that of 1-butanol and the presence of 1-butanol contributed to increase of the reaction rate as well as yield. The maximum yield of ca. 98 wt% was achieved under the optimized condition.

Novel crosslinked thin polymer networks based on vegetable oil hydroxy fatty acids (HFAs) were prepared by UV photopolymerization and their mechanical proper- ties were evaluated. Two raw materials, castor oil and 7,10-dihydroxy-8(E)-octadecenoic acid (DOD) were used as sources of mono- and di-HFAs, respectively. Poly (ethylene glycol) (PEG) diacrylate and poly(e-caprolac- tone) diacrylate were synthesized and used as crosslinking agents to form crosslinked polymer networks by UV-ini- tiated free-radical polymerization with acrylated castor oil or acrylated DOD. The synthesis of acrylate derivatives was confirmed using FT-IR and 1 H-NMR spectroscopic techniques. The composition of the reaction mixture and the type/length of crosslinking agent were changed to obtain crosslinked polymer networks with various mechanical properties. For polymers prepared from high molecular weight (20,000) PEG, a 58-60% of the initial weights decreased in 35 days in phosphate buffer solution (pH 7.2) containing lipase enzyme. These potentially bio- degradable polymers based on vegetable oil HFAs can be used as eco-friendly materials for various applications to replace the existing petroleum-based polymers currently used.

Structured lipids were synthesized by the acidolysis of corn oil by caprylic acid in supercritical carbon dioxide (SCCO2) with Lipozyme RM IM from Rhizomucor miehei. The effects of pressure and temperature on the reaction were studied. To compare the degrees of acyl migration in the SCCO2 and solvent-free reaction systems, the effects of reaction time on the degree of acyl migration were also studied. The highest mole percentage incorporation of caprylic acid (62.2 mol%) occurred at 24.13 MPa in SCCO2. The overall incorporation of caprylic acid in the SCCO2 system remained higher than that in the solvent-free system at every temperature tested. This trend was observed more clearly at lower temperatures (35–55°C) than at higher temperatures (65–75°C). Acyl migration with both reaction systems was low, with a negligible difference between them up to 12 h, after which the degree of acyl migration in the solvent-free system increased rapidly with time up to 24 h compared with the SCCO2 system.

Tocol levels in the milling fractions of rice, barley, corn, wheat, and soybeans were analyzed by HPLC with a fluorescence detector. Among all milling fractions tested in this study, rice germ had the highest total tocol levels. In the four milling fractions of barley, except pearling flour, all eight tocol isomers were detected, and they were more uniformly distributed than in any other cereal grains measured in this study. The total tocol and α-tocopherol levels of wheat germ were significantly (P

Structured lipids were synthesized by acidolysis of perilla oil and caprylic acid using two lipases, Lipozyme RM IM from Rhizomucor miehei and Lipozyme TL IM from Thermomyces lanuginosa. Effects of molar ratio, reaction time, reaction temperature, enzyme load, and solvent content on acidolysis reactions were studied. The solvent content ranged from 0.0 (solvent-free) to 85.3%. The results showed that the incorporation increased in parallel with solvent content to 49.0% with Lipozyme RM IM and to 63.8% with Lipozyme TL IM. After 24 h incubation in n-hexane, caprylic acids were incorporated to 48.5 mol% with Lipozyme RM IM and to 51.4 mol% with Lipozyme TL IM, respectively, whereas linolenic acid content was reduced from 61.4 to 31.5 mol% with Lipozyme RM IM and to 28.4 mol% with Lipozyme TL IM, respectively. Lipozyme TL IM showed a higher acyl migration rate than Lipozyme RM IM when acidolysis was performed in the reaction system containing n-hexane as a solvent, whereas the difference in acyl migration between the two lipases in the solvent-free system was negligible.

The new microbial isolate Pseudomonas aeruginosa (PR3) has been reported to produce from oleic acid a new compound, 7,10-dihydroxy-8(E)-octadecenoic acid (DOD), with 10-hydroxy-8-octadecenoic acid (HOD) being a probable intermediate. The production of DOD involves the introduction of two hydroxyl groups at carbon numbers 7 and 10, and a rearrangement of the double bond from carbons 9-10 to 8-9. It has been shown that the 8-9 unsaturation of HOD was possibly in the cis configuration. Now we report that the rearranged double bond of HOD is trans rather than cis, as determined by spectral data. Also, it was found that the 10-hydroxyl was in the S-configuration as determined by gas chromatographic separation of R- and S-isomers after preparation of the (-)-menthoxycarbonyl derivative of the hydroxyl group followed by oxidative cleavage of the double bond and methyl esterification. This latter result coincides with our recent finding that the main final product, DOD, is in the 7(S), 10(S)-dihydroxy configuration. In addition, a minor isomer of HOD (about 3 %) with the 10(R)-hydroxyl configuration was also detected. From the data obtained herein, we concluded that 10(S)-hydroxy-8(E)-octadecenoic acid is the probable intermediate in the bioconversion of oleic acid to 7(S), 10(S)-dihydroxy-8(E)-octadecenoic acid by PR3.