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1.
Y. -Y. Linko M. Lämsä A. Huhtala P. Linko 《Journal of the American Oil Chemists' Society》1994,71(12):1411-1414
Lipase-catalyzed transesterification (alcoholysis) of lowerucic acid rapeseed oil and 2-ethyl-1-hexanol without an additional
organic solvent was studied in stirred batch reactors. Of a number of commercially available enzymes investigated, the best
results were obtained with aCandida rugosa lipase. The optimal transesterification conditions were an oil/alcohol molar ratio of 1∶2.8, a minimum of 1.0% (w/w) added
water, and with a temperature of 37–55°C. Under the optimal conditions, a nearly complete conversion was obtained in one hour
with 14.6% (w/w) lipase, whereas 0.3% (w/w) lipase required 10 h for similar results. The enzyme was inactivated at 60°C. 相似文献
2.
Yu-Yen Linko Xiao Yan Wu 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1996,65(2):163-170
Two distinct lipase forms were obtained from Candida rugosa lipase by Phenyl Sepharose hydrophobic interaction and DEAE Sepharose ion exchange chromatography, L1 at 45% yield and L2 at 4·7% yield. Both purified lipases were able to catalyse esterification of 1-butanol and oleic acid and trans-esterification of 2-ethyl-1-hexanol and rapeseed oil. Lipase L1 gave a 98% yield for esterification over 12 h and a 99% conversion of rapeseed oil for trans-esterification over 24 h. The minor fraction L2 gave a 97% yield for esterification over 30 h and only a 79% conversion for trans-esterification over 24 h. The superiority of fraction L1, especially in trans-esterification, could be clearly shown by reversed phased HPLC analysis. Sodium deoxycholate treatment of the purified main lipase L1 considerably improved the initial rate in both esterification and trans-esterification. 相似文献
3.
Gerald P. McNeill Philip E. Sonnet 《Journal of the American Oil Chemists' Society》1995,72(2):213-218
Three lipases were compared for their ability to hydrolyze high erucic acid rapeseed oil, with the objective of concentrating
the erucic acid in a single glyceride fraction. Lipase fromPseudomonas cepacia released all fatty acids rapidly and did not result in selective distribution of erucic acid.Geotrichum candidum lipase released C20 and C22 fatty acids extremely slowly, resulting in their accumulation in the di- and triglyceride fractions.
Less than 2% of the total erucic acid was found in the free fatty acid (FFA) fraction. Lipase fromCandida rugosa released erucic acid more slowly than C20 and C18 fatty acids at 35°C but only resulted in a limited accumulation of the
erucic acid in the di- and triglyceride fractions. However, when hydrolysis catalyzed byC. rugosa lipase was carried out below 20°C, the reaction mixture solidified and was composed solely of FFAs and diglycerides. The
diglyceride fraction contained approximately 95% erucic acid while about 20% of the total erucic acid was found in the FFA
fraction. It is concluded that hydrolysis at low temperature withC. rugosa lipase results in a higher purity of erucic acid in the glyceride fraction than can be obtained withG. candidum lipase, but with considerable loss of erucic acid to the FFA fraction. 相似文献
4.
An extracellular lipase from the fungusPythium ultimum was active in an invert [water-in-oil] emulsion consisting of 4% water emulsified into edible oils with taurocholic acid
as the surfactant. The pH range for optimum lipolytic activity was 7.5–8.5, and the optimum temperature for activity was 45°C.
Specific activity of the purified lipase was 919.5 μmol/min/mg protein in the invert emulsion. Water content of the invert
emulsion influenced activity of the lipase differently, depending on the substrate. The rate of olive oil hydrolysis with
thePythium lipase decreased with time, possibly due to inactivation of the enzyme and inhibition by free fatty acid products of the
reaction. Total hydrolysis of olive oil by thePythium lipase was compared with that by lipases fromCandida rugosa andRhizopus arrhizus in the invert emulsion. Hydrolysis essentially ceased within 24 h or less for the lipases from each source. However, the
addition of aqueous solution at 8 h from the beginning of incubation stimulated hydrolysis byC. rugosa andR. arrhizus lipases by 1.8-fold and 2.5-fold, respectively, but not by theP. ultimum lipase, over corresponding controls after 48 h. 相似文献
5.
Yuji Shimada Yoshinori Hirota Takashi Baba Shinichiro Kato Akio Sugihara Shigeru Moriyama Yoshio Tominaga Tadamasa Terai 《Journal of the American Oil Chemists' Society》1999,76(10):1139-1142
l-Menthol has been widely used as a food additive and an ingredient of cosmetics, and it is esterified to moderate the strong
flavor. We attempted esterification of l-menthol with long-chain unsaturated fatty acid in an organic solvent-free enzymatic system. Commercially available lipases
were screened, and Candida rugosa lipase was selected as a catalyst. Several factors affecting the esterification were investigated, and the reaction conditions
were determined as follows: A reaction mixture of l-menthol/fatty acid (1:3, mol/mol), 30% water, and 700 units of the lipase per gram of reaction mixture was incubated at 30°C
with stirring. After 24 h under these conditions, the esterification extents of l-menthol with oleic, linoleic, and α-linolenic acids reached 96, 88, and 95%, respectively. The structure of the esterified
product was confirmed by mass, infrared, and nuclear magnetic resonance spectroscopies. Bacause Candida lipase acted strongly on l-menthol and very weakly on d-menthol, dl-menthol was esterified with oleic acid under the same conditions. The reaction showed high enantioselectivity; the enantiomeric
ratio (E) was 31, and enantiomeric excess (ee) of l-menthyl oleate reached 88% after 32 h. 相似文献
6.
Transesterification of trimethylolpropane and rapeseed oil methyl ester to environmentally acceptable lubricants 总被引:7,自引:0,他引:7
Esa Uosukainen Yu-Yen Linko Merja Lämsä Tommi Tervakangas Pekka Linko 《Journal of the American Oil Chemists' Society》1998,75(11):1557-1563
Biodegradable trimethylolpropane [2-ethyl-2-(hydroxymethyl)-1,3-propanediol] esters of rapeseed oil fatty acids were synthesized
by transesterification with rapeseed oil methyl ester both by enzymatic and chemical means, both in bench and pilot scales.
Nearly complete conversions were obtained with both techniques. A reduced pressure of about 2 to 5 kPa, to remove the methanol
formed during transesterification, was critical for a high product yield. The quantity of added water was also critical in
the biocatalysis. Candida rugosa lipase was used as biocatalyst and an alkaline catalyst in chemical transesterifications. In biocatalysis the maximum total
conversion to trimethylolpropane esters of up to 98% was obtained at 42°C, 5.3 kPa, and 15% added water. The maximum conversion
of about 70% to the tri-ester was obtained at the slightly higher temperature of 47°C. The reaction time was longer in the
biocatalysis, but considerably higher temperatures were required in chemical synthesis. In the chemical synthesis tri-ester
yields increased when the temperature was first held at 85 to 110°C for 2.5 h and subsequently increased to up to 120°C for
8 h. The trimethylolpropane esters obtained were tested as biodegradable hydraulic fluids and compared to commercially available
hydraulic oils. The hydraulic fluids based on trimethylolpropane esters of rapeseed oil had good cold stability, friction
and wear characteristics, and resistance against oxidation at elevated temperatures. 相似文献
7.
Yomi?Watanabe Yoshie?Yamauchi-Sato Toshihiro?Nagao Takaya?Yamamoto Kentaro?Tsutsumi Akio?Sugihara Yuji?Shimada
We attempted to produce MAG of CLA through lipase-catalyzed esterification of a FFA mixture containing CLA (referred to as
FFA-CLA) with glycerol. Screening of lipases showed that MAG-CLA was produced efficiently at 5°C with Penicillium camembertii, Rhizopus oryzae, and Candida rugosa lipases. Among them, C. rugosa lipase was selected because the lipase is widely used as a catalyst for oils and fats processing. The reaction was conducted
with agitation of a 300-g mixture of FFA-CLA/glycerol (1∶5, mol/mol), a 200-U/g mixture of C. rugosa lipase, and 2% water. When the reaction was conducted at 30°C, the esterification scarcely proceeded, owing to inhibition
of the reaction by glycerol. But the reaction at 5°C eliminated the inhibition and produced MAG efficiently: The degree of
esterification reached 93.8% after 58 h, and MAG content in the reaction mixture was 88.4 wt%. To reduce the reaction time,
the reactor was connected with a vacuum pump after 24 h, and the reaction was continued with dehydration at 5 mm Hg. The degree
of esterification reached 94.7% after 24 h of dehydration (48 h in total), and MAG content increased to 93.0 wt%. Candida rugosa lipase acted a little more strongly on cis-9, trans-11 CLA than on trans-10,cis-12 CLA, but the contents of the two isomers in MAG obtained from a 48-h reaction were the same as the contents in FFA-CLA. 相似文献
8.
Philip E. Sonnet Gerald P. McNeill Wang Jun 《Journal of the American Oil Chemists' Society》1994,71(12):1421-1423
Silica gel is a useful support for the lipases ofGeotrichum candidum. Esterification of selected fatty acids and alcohols proceeded to 85–92% conversion in hydrocarbon solvents, and the degree of esterification was increased to 96–98% by adding 4Å molecular sieves at later stages of reaction. The equilibrium ratio of ester to fatty acid (butyl oleate to oleic) was determined for the supported lipase in a number of solvents and ranged from 92∶8 in hexane and isooctane to 16∶84 int-butanol. The essential character of the enzyme seemed unimpaired by deposition onto silica gel as judged by fatty acid selectivity and stereoselectivity. 相似文献
9.
The enzymatic synthesis of glycerides from glycerol and oleic acid in organic solvent was studied, and the optimal conditions
for glyceride synthesis by lipases were established. Of the commercially available lipases that were investigated, Candida rugosa lipase and porcine pancreas lipase resulted in the highest extent of esterification. Iso-octane and hexane were particularly
useful organic solvents in glyceride synthesis. The water content in the reaction mixture was of primary importance. For C. rugosa lipase and porcine pancreas lipase, the optimal water contents were 5 and 1%, respectively. Candida rugosa lipase and porcine pancreas lipase manifested contrasting positional specificities in glyceride synthesis. 相似文献
10.
Casimir C. Akoh 《Journal of the American Oil Chemists' Society》1994,71(3):319-323
Two immobilized lipases fromCandida antarctica (SP 382) andC. cylindraceae, nowrugosa (2001), catalyzed the synthesis of novel acetylated glucose fatty acid esters with glucose pentaacetate (GP) and Trisun 80
(80% oleic) vegetable oil or methyl oleate as substrates in organic solvents. The relative yield was between 6.4–52%, and
the incorporation of oleic acid onto the glucose was between 31–100%. In addition, these enzymes were able to catalyze the
synthesis of glucose fatty acid esters with free glucose as the sugar substrate. The highest oleic acid incorporation (100%)
was obtained in benzene with SP 382 lipase and Trisun 80 as the acyl donor. With methyl oleate as the acyl donor, greater
incorporation was obtained in benzene (90.5%) compared to 75% in isooctane. The 2001 lipase was better in benzene/pyridine
(2∶1 vol/vol) 74%) and chloroform (61%) compared to benzene and isooctane. However, with free glucose and Trisun 80 as substrates,
both enzymes gave acceptable levels of oleic acid incorporation (82–100%) in benzene, benzene/pyridine and pyridine. The best
conditions for the ester interchange reaction reported are: lipase (10% by weight of substrate); incubation time 48 h; molar
ratio of Trisun/GP 1∶2; 3 mL solvent and 3% added water. These glucose esters have potential applications as emulsifiers in
food, cosmetics and pharmaceutical formulations. 相似文献
11.
N. Madhusudhana Rao V. M. Shanmugam 《Journal of the American Oil Chemists' Society》2000,77(6):605-608
Engineering media for optimal product yield in enzyme-catalyzed reactions is an important strategy. We report here synthesis
of dodecyl oleate and oleyl oleate by lipase (Candida rugosa) in solvent-free substrate foams. Ester formation was characterized with respect to enzyme concentration, pH, temperature,
and substrate concentration. The kinetics of ester formation suggest that the formation of ester was 80% complete in 2h. The
pH and temperature optima of lipase suggest that the behavior of lipase in substrate foams was similar to its behavior in
water or in organic solvents. The denaturing effect of foams on enzyme was evaluated. Rapid loss in activity (>70% in 1 h)
was observed in the presence of oleic acid and dodecanol. The large surface areas generated in aqueous foams offer better
accessibility of substrate to lipase for esterification. 相似文献
12.
Philip E. Sonnet Thomas A. Foglia Mary Welch Baillargeon 《Journal of the American Oil Chemists' Society》1993,70(10):1043-1045
The relative reactivities of several long-chain fatty acids in esterifications with 1-butanol catalyzed by lipases ofGeotrichum candidum were evaluated. As has been noted previously, these lipases are not uniformly highly selective forcis-9 unsaturated fatty acids. However, the lipase preparations examined do uniformly discriminate against fatty acids having
a chainlength greater than C-18 such as erucic acid. The reactivities of γ-linolenic and ricinoleic acid were also low compared
to that of oleic. An examination of the effect of the alcohol upon the relative reactivities of acids showed that one could
enhance fatty acid selectivity by proper choices of alcohol. For example, oleic acid esterifies 2.5 times faster than palmitic
acid with 1-butanol catalyzed by Amano GC-4 lipase, but esterifies over 50 times faster with 2-methyl-1-propanol or cyclopentanol. 相似文献
13.
S. Bradoo R. K. Saxena R. Gupta 《Journal of the American Oil Chemists' Society》1999,76(11):1291-1295
High yields of ascorbyl palmitate (6-O-palmitoyl-l-ascorbic acid) were obtained by lipase-mediated esterification using Bacillus stearothermophilus SB 1 lipase. The final yield was greatly influenced by the initial water content of the system, quantity of enzyme, and molar
ratio of palmitic acid to l-ascorbic acid. Reaction rates increased directly with temperature from 40 to 100°C. Maximum conversion (97%) was achieved
after 30 min at 100°C (solvent-free), 1 h at 80°C (solvent-free), and 2 h at 60°C (solvent/hexane). The synthesis was scaled
up to 1-l volume with 95% conversion using 50 mmoles of ascorbic acid and 250 mmoles of palmitic acid in hexane. Similar yields of
ester were obtained in five repetitive cycles using 5 g enzyme immobilized on Accurel. The present B. stearothermophilus SB 1 lipase was a more efficient catalyst for the synthesis of ascorbyl palmitate than other commercial lipases. 相似文献
14.
The synthesis/hydrolysis of wax esters was studied in an aqueous solution using purified rat pancreatic lipase, porcine pancreatic
carboxylester lipase, and Pseudomonas fluorescens lipase. The equilibrium between wax ester synthesis and hydrolysis favored ester formation at neutral pH. The synthesizing
activities were measured using free fatty acid or triacylglycerol as the acyl donor and an equimolar amount of long-chain
alcohol as the acyl acceptor. When oleic acid and hexadecanol emulsified with gum arabic were incubated with these lipases,
was ester was synthesized, in a dose- and time-dependent manner, and the apparent equilibrium ratio of palmityl oleate/free
oleic acid was about 0.9/0.1. These lipases catalyzed the hydrolysis of palmityl oleate emulsified with gum arabic, and the
apparent equilibrium ratio of palmityl oleate/free oleic acid was also about 0.9/0.1. The apparent equilibrium ratio of wax
ester/free fatty acid catalyzed by lipase depended on incubation pH and fatty alcohol chain length. When equimolar amounts
of trioleoylglycerol and fatty acyl alcohol were incubated with pancreatic lipase, carboxylester lipase, or P. fluorescens lipase, wax esters were synthesized dose-dependently. These results suggest that lipases can catalyze the synthesis of wax
esters from free fatty acids or through degradation of triacylglycerol in an aqueous medium. 相似文献
15.
Esterification of five positional isomers of acetylenic fatty acids [viz. 9:1(2a), 11:1(10a), 18:1(6a), 18:1(9a) and 22:1(13a)] of different chain lengths with n-butanol in n-hexane in the presence of eight different lipases [Lipozyme IM 20 (Rhizomucor miehei), Lipolase 100T (R. miehei), Novozyme 435 (Candida antarctica), PPL (porcine pancreatic lipase), CCL (C. cylindracea), PS-D (Pseudomonas cepacia), Lipase A-12 (Aspergillus niger) and Lipase AY-30 (C. rugosa)] was studied. 2-Nonynoic acid was not esterified except when catalyzed by the lipase from C. antarctica (Novozyme 435) to give 42% butyl ester after 48 h. The lipases from A. niger (Lipase A-12) and C. rugosa (Lipase AY-30) showed poor biocatalytic behavior in the esterification of the acetylenic fatty acids studied. 10-Undecynoic
acid gave the highest conversion rate of esterification with each kind of lipase used. 6-Octadecynoic acid showed a marked
degree of resistance to esterification carried out in the presence of C. cylindracea (CCL), P. cepacia (PS-D), or porcine pancreatic (PPL) lipase but not significantly in the presence of the lipases of R. miehei (Lipozyme IM 20), R. miehei (Lipolase 100T), or Novozyme 435. 9-Octadecynoic acid and 13-docosynoic acid were not discriminated and were readily esterified
by the remaining six lipases, but when compared to oleic acid the acetylenic fatty acids were comparatively much slower in
conversion to the esters. 相似文献
16.
Marie D. Jonzo Abel Hiol Danielle Druet Louis C. Comeau 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1997,69(4):463-469
Candida rugosa lipase (CRL) has been immobilized on two kinds of ion-exchange resins, Duolite A 568 and Amberlite IRC 50. These preparations were investigated as a tool for the production of cholesterol oleate in organic media. An increase in temperature up to 40°C increased the rate of reaction and improved the final ester yield. Under optimal conditions, the reaction yield was followed as a time function, for both lipase preparations with an initial water content of 20%. Then, it was observed that about 78% of the oleic acid was esterified after 10 h using CRL immobilized on Duolite, whereas 73% synthesis of cholesterol oleate was reached with CRL immobilized on Amberlite, for the same incubation time. Also, a difference in reaction yield was noticed for the preparations containing sorbitol. In fact, sorbitol treatment might improve the activity of immobilized lipase by preserving the watershell around the catalyst and by increasing the accessibility of the active site to the substrates. In this way, the reaction yield was enhanced, and an increase of 10% synthesis of cholesterol oleate was obtained in both cases. © 1997 SCI. 相似文献
17.
Yoshinori?Hirota Toshihiro?Nagao Yomi?Watanabe Masaharu?Suenaga Seiichi?Nakai Aktohiro?Kitano Akio?Sugihara Yuji?Shimada
Soybean oil deodorizer distillate (SODD) contains steryl esters in addition to tocopherols and sterols. Tocopherols and sterols
have been industrially purified from SODD but no purification process for steryl esters has been developed. SODD was efficiently
separated to low b.p. substances (including tocopherols and sterols) and high b.p. substances (including 11.2 wt% DAG, 32.1
wt% TAG, and 45.4 wt% steryl esters) by molecular distillation. The high b.p. fraction is referred to as soybean oil deodorizer
distillate steryl ester concentrate (SODDSEC). We attempted to purify steryl esters after a lipase-catalyzed hydrolysis of
acylglycerols in SODDSEC. Screening of industrially available lipases indicated that Candida rugosa lipase was most effective. Based on the study of several factors affecting hydrolysis, the reaction conditions were determined
as follows: ratio of SODDSEC/water, 1∶1 (w/w); lipase amount, 15 U/g reaction mixture; temperature, 30°C. When SODDSEC was
agitated for 24 h under these conditions, acylglycerols were almost completely hydrolyzed and the content of steryl esters
did not change. However, study with a mixture of steryl oleate/trilinolein (1∶1, w/w) indicated that about 20% of constituent
FA in steryl esters were exchanged with constituent FA in acylglycerols. Steryl esters in the oil layer obtained by the SODDSEC
treatment with lipase were successfully purified by molecular distillation (purity, 97.3%; recovery, 87.7%). 相似文献
18.
Lipase-catalyzed synthesis of structured triacylglycerides from 1,3-diacylglycerides 总被引:4,自引:0,他引:4
A new method for the lipase-catalyzed synthesis of structured TAG (ST) is described. First, sn1,3-dilaurin or-dicaprylin were enzymatically synthesized using different published methods. Next, these were esterified at
the sn2-position with oleic acid or its vinyl ester using different lipases. Key to successful enzymatic synthesis of ST was the
choice of a lipase with appropriate FA specificity, i.e., one that does not act on the FA already present in the sn1,3-DAG, but that at the same time exhibits high selectivity and activity toward the FA to be introduced. Reactions were performed
in the presence of organic solvents or in solvent-free systems under reduced pressure. With this strategy, mixed ST containing
the desired compounds 1,3-dicaprylol-2-oleyl-glycerol or 1,3-dilauroyl-2-oleyl-glycerol (CyOCy or LaOLa) were obtained at
87 and 78 mol% yield, respectively, using immobilized lipases from Burkholderia cepacia (Amano PS-D) in n-hexane at 60°C. However, regiospecific analysis with porcine pancreatic lipase indicated that in CyOCy, 25.7% caprylic acid
and in LaOLa 11.1% lauric acid were located at the sn2-position. Oleic acid vinyl ester was a better acyl donor than oleic acid. Esterification of sn1,3-DAG and free oleic acid gave very low yield (<20%) of ST in a solvent system and moderate yield (>50%) in a solvent-free
system under reduced pressure. 相似文献
19.
Terry A. Isbell Lindsay A. Green Stephanie S. DeKeyser Linda K. Manthey James A. Kenar Steven C. Cermak 《Journal of the American Oil Chemists' Society》2006,83(5):429-434
In the extraction of oils from seeds of the genus Coriandrum, GC separations of petroselinate from oleate often gave poor resolution of these two isomers. Oleic and petroselinic acids
were esterified with a series of alcohols (methanol, ethanol, 1-propanol, 2-propanol, 2-methyl-1-propanol, 1-butanol, 3-methyl-1-butanol,
and 2-ethyl-1-hexanol). GC resolution of the Δ6 from the Δ9 and Δ11 octadecenoates was examined for all ester derivatives
on a polar phase column. The Δ6 and Δ9 isomers were unresolved as methyl esters; however, the 2-ethyl-1-hexyl esters gave
baseline separation of all three isomers under temperature programming conditions. When isothermal conditions were optimized
for each ester, separation of these isomers was possible with good resolution values (>89%) for all the alcohols except methanol,
which had a partial resolution of 51%. The rates of esterification of all the alcohols were determined for reactions with
both oleic acid and triolein using potassium hydroxide as the esterification catalyst. Methanol gave the largest rate constant
in both acid and oil esterification reactions with a rate constant 10-fold better than all of the other alcohols. Based on
rates of reaction, resolution of petroselinate from oleate, and removal of residual alcohol, the ethyl ester derivative appears
to be the best choice for seed oils containing petroselinic acid. 相似文献
20.
Gerald P. McNeill Robert G. Ackman Stephen R. Moore 《Journal of the American Oil Chemists' Society》1996,73(11):1403-1407
Lipase hydrolysis was evaluated as a means of selectively enriching long-chain ω3 fatty acids in fish oil. Several lipases
were screened for their ability to enrich total ω-3 acids or selectively enrich either docosahexaenoic acid (DHA) or eicosapentaenoic
acid (EPA). The effect of enzyme concentration, degree of hydrolysis, and fatty acid composition of the feed oil was studied.
Because the materials that were enriched in long-chain ω3 acids were either partial glycerides or free fatty acids, enzymatic
reesterification of these materials to triglycerides by lipase catalysis was also investigated. Hydrolysis of fish oil by
eitherCandida rugosa orGeotrichum candidum lipases resulted in an increase in the content of total ω3 acids from about 30% in the feed oil to 45% in the partial glycerides.
The lipase fromC. rugosa was effective in selectively enriching either DHA or EPA, resulting in a change of either the DHA/EPA ratio or the EPA/DHA
ratio from approximately 1:1 to 5:1. Nonselective reesterification of free fatty acids or partial glycerides that contained
ω3 fatty acids could be achieved at high efficiency (approximately 95% triglycerides in the product) by using immobilizedRhizomucor miehei lipase with continuous removal of water. 相似文献