• KSBB Journal
• /
• v.14 no.2
• /
• pp.225-229
• /
• 1999

Enzymatic resolution reactions were investigated using Candida rugosa lipase for the production of potically pure S-(+)-Ketoprofen. When the enzymatic hydroysis (and esterification) of recemic ketoprofen esters (and recemic ketoprofen with alcohol) was investigated comparatively, aqueous media was more specific for S-enantiomer than organic media. In the enzymatic hydrolysis of racemic ketoprofen ethyl ester in aqueous media, optimal temperature and pH for enantioselectivity were $37^{\circ}C$ and 4, respectively. The stereoselectivity of the enzyme was enhanced by adding dialcohols such as ethylene glycol and propylene glycol. The enantiomeric ratio obtained in the 40 %(v/v) ethylene glycol was 2-fold higher than that without the additive. By adding $CH_2Cl_2$, $CHCl_3$ and $CCl_4$ (5%,v/v), the enantioselectivity was reversed. A dramatic increase in the stereoselectivity was achieved using lipase purified by anion exchange chromatography. The type A lipase(the first eluted lipase fraction) showed an enantiomeric ratio of >100, whereas the type B lipase(the second eluted lipase fraction) exhibited enantimomer ratio of 9.0 in the hydrolysis of racemic ketoprofen ethyl ester.

• Food Science and Preservation
• /
• v.18 no.5
• /
• pp.721-728
• /
• 2011

1(3)-palmitoyl-2-oleoyl-3(1)-stearoyl-(POS)-glycerol-enriched reaction products were synthesized from camellia oil, palmitic ethyl ester, and stearic ethyl ester via lipase-catalyzed interesterification. Response surface methodology (RSM) was employed to optimize the production of the POS-enriched reaction product (Y1, %) and the stearicand palmitic-acid contents at the sn-2 position due to acyl migration (Y2, %). The reaction factors were the enzyme amount (X1, 2-6%), reaction time (X2, 60-360 min), and substrate molar ratio of camellia oil to palmitic ethyl ester and stearic ethyl ester (X3, 1-3 mol). The predictive models for Y1 and Y2 were adequate and reproducible as no lack of fit was signified (0.128 and 0.237) and as there were satisfactory levels of R2 (0.968 and 0.990, respectively). The optimal conditions for the reaction product for maximizing Y1 while minimizing Y2 were predicted at the reaction combination of 5.86% enzyme amount, 60 min reaction time, and 1:3 substrate molar ratio (3 moles of palmitic ethyl ester and 3 moles of stearic ethyl ester). Actual reaction was performed under the same conditions as above, and the resulting product contained 20.19% TAG-P/O/S and 12.71% saturated fatty acids at the sn-2 position.

• Food Science and Biotechnology
• /
• v.18 no.3
• /
• pp.803-807
• /
• 2009

Solid fats were esterified with solid phase of rice bran oil (S-RBO), palm stearin (PS), and conjugated linoleic acid (CLA) at 2 substrate mole ratios (S-RBO:PS:CLA of 1:1:2 and 1:3:4). The major fatty acids were palmitic, oleic, and CLA in 36 hr products. The solid fat content (SFC) of the 1:1:2 product was 12.8% while the SFC of 1:3:4 product was 45.1% at $20^{\circ}C$. The SFCs after $20^{\circ}C$ reduced when the reaction time increased from 1 to 36 hr, suggesting that the change of triacylglycerol species was augmented by extending reaction time.

• Microbiology and Biotechnology Letters
• /
• v.37 no.4
• /
• pp.365-370
• /
• 2009

For the production of diglyceride (DG) containing medium chain fatty acid, which could be utilized as a substrate to structured lipid production, monoglyceride (MG) and caprylic acid were reacted in the presence of lipase. The reaction system was well mixed homogeneously without using any organic solvent. Among the lipases investigated, Lipozyme RM IM and Novozym 435 were selected on the basis of equilibrium DG yields from the medium chain fatty acid and MG. And reaction conditions such as addition of molecular sieve, water content of immobilized lipase, reaction temperature, and mole ratio of MG/caprylic acid are optimized to increase DG production by using Lipozyme RM IM. DG content of reaction mixture showed 8% increase by adding molecular sieve to reaction mixture. Removal of water from the immobilized lipase could affect seriously equilibrium content of DG. More than 2.8%(w/w) removal of water from the support could make 44% of DG. Optimum temperature was found to $60^{\circ}C$. Temperature shift from $60^{\circ}C$ to $25^{\circ}C$ resulted in increase of free fatty acid (FFA) content. The equilibrium DG yield was not seriously affected by on MG/caprylic acid molar ratio. However, at the stoichiometric ratio of 1:1 the highest DG yield was obtained. Increasing MG/caprylic acid ratio from 0.3 to 1.8 decreased FFA content from 34% to 13%, while MG content increased from 27% to 50%.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.38 no.8
• /
• pp.1062-1068
• /
• 2009

Diacylglycerol (DAG) were synthesized by enzymatic esterification of glyceryl monooleate (GMO) and conjugated linoleic acid (CLA) in a shaking water bath. The reaction was catalyzed by Lipozyme TLIM (immobilized lipase from Thermomyces lanuginosa). Effects of reaction time, molar ratio, enzyme road and molecular sieves were studied. Results of normal-phase high performance liquid chromatography (NP-HPLC) analysis were performed. At 1:1, 2:1 and 3:1 (GMO : CLA) molar ratio and Lipozyme TLIM of 20% amount, DAG were produced in 42.6, 54.4 and 54.6 area% in 1 hr, respectively. When different Lipozyme TLIM amounts (2, 5, 10, 20%) were used with 2:1 (GMO : CLA) molar ratio, DAG were produced 21.4 (24 hr), 51.7 (12 hr), 56.2 (6 hr) and 54.4 (1 hr) area%, respectively. The reaction in the absence of molecular sieves increased DAG contents. The maximum DAG concentration conditions were obtained with molar ratio of 2:1 (GMO : CLA), lipase concentration of 10% (of substrate), 10% molecular sieves and reaction time of 6 hours at 55$^{\circ}C$. Under this reaction condition, produced DAG-rich oil was composed of 69 area% DAG, 7.9 area% TAG, 2 area% FFA, and 21.1 area% MAG.

• Microbiology and Biotechnology Letters
• /
• v.16 no.3
• /
• pp.250-258
• /
• 1988

Lipases are well known as the enzymes which catalyze the hydrolysis of ester bonds combining aliphatic chains and glycerol on mono-, di- and triglycerides. Their reactions are characterized by be-ing heterogeneous and catalyzing the water-insoluble substrates. This property has been one of the Hurdles which delayed the application of lipases in fats and oils industry, However, with the development of biological reaction system of which organic solvent is introduced in part or whole as the reaction media, enzymatic manipulation of fats and oils is attracting increasing attention from the academic and industrial sectors. Trials in two-phase system and reversed micellar system to produce fatty acids through enzymatic hydrolysis of triglycerides preyed to be efficient in respect to volumetric productivity, fat hydrolysis rate, product separation, etc. In organic solvent system lipases have been found to have the ability to catalyze aminolysis, transesterification, esterification, thiotransesterification and oximolysis that are virtually impossible to catalyze in water. The organic solvent system is being extensively used in interesterifying glycerides to produce a fat with the modified physical and chemical nature.

• Food Science and Preservation
• /
• v.16 no.2
• /
• pp.246-252
• /
• 2009

Diacylglycerol(DAG) was produced by enzymatic esterification of glyceryl mono-oleate(GMO) and conjugated linoleic acid(CLA) in a stirred-batch type reactor. The reaction was catalyzed by lipozyme RMIM(an immobilized lipase from Rizomucor miehei). DAG was isolated by a short-path distillation process and decolorized. DAG oil was composed of 87.3% DAG, 11.4% triacylglycerol(TAG), and 1.5% monoacylglycerol(MAG)(all w/w). Major fatty acids in DAG oil were oleic acid(54%), CLA(31.1%), and linoleic acid(7%). DAG oil iodine,and acid values were 108.8, 2.57, and 1, respectively. The DAG oil solid fat index(SFI) and thermograms were obtained using differential scanning calorimetry.