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1.
Yoshitsugu Kosugi Qing-long Chang Kenji Kanazawa Hiroshi Nakanishi 《Journal of the American Oil Chemists' Society》1997,74(11):1395-1399
Hydrolysis specificities of lipase from Rhizomucor miehei were compared for various fatty acyl ethyl esters. Activity yields of immobilized lipases, measured with 1 mM substrate,
were more than 100%. Differences in hydrolysis rate and affinity for the substrates between lipase preparations were also
typically higher during hydrolysis of substrates at 100 mM than at 1 mM, indicating better mass transfer effects for 1-mM
substrates. The native lipase showed higher affinity for polyunsaturated fatty acid substrates at 1 mM than at 100 mM. Hydrolysis
rates for 1-mM substrates were observed with immobilized lipases, fixed on anion exchange resin with glutaraldehyde and on
cation exchange carrier with carbodiimide, and suggested some modification of the basic amino acid related to the lid of R. miehei lipase. Activation with these bifunctional reagents was not observed for 100-mM substrates, indicating that interfacial activation
always occurred because of aggregation of 100-mM substrates. These results show that lipase from R. miehei recognizes molecular aggregation of lipids, and that various changes occur in the hydrolysis specificities for fatty acids. 相似文献
2.
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
3.
Lipase-catalyzed modification of borage oil: Incorporation of capric and eicosapentaenoic acids to form structured lipids 总被引:2,自引:0,他引:2
Casimir C. Akoh Charment O. Moussata 《Journal of the American Oil Chemists' Society》1998,75(6):697-701
Two immobilized lipases, nonspecific SP435 from Candida antarctica and sn-1,3 specific IM60 from Rhizomucor miehei, were used as biocatalysts for the restructuring of borage oil (Borago officinalis L.) to incorporate capric acid (10:0, medium-chain fatty acid) and eicosapentaenoic acid (20:5n-3) with the free fatty acids
as acyl donors. Transesterification (acidolysis) reactions were carried out in hexane, and the products were analyzed by gas-liquid
chromatography. The fatty acid profiles of the modified borage oil were different from that of unmodified borage oil. Higher
incorporation of 20:5n-3 (10.2%) and 10:0 (26.3%) was obtained with IM60 lipase, compared to 8.8 and 15.5%, respectively,
with SP435 lipase. However, SP435 lipase was able to incorporate both 10:0 and 20:5n-3 fatty acids at the sn-2 position, but the IM60 lipase did not. Solvents with log P values between 3.5 and 4.5 supported the acidolysis reaction better than those with log P values between −0.33 and 3.0. 相似文献
4.
Susanne Bech Pedersen Gunhild Hølmer 《Journal of the American Oil Chemists' Society》1995,72(2):239-243
The fatty acid specificity of the lipase fromRhizomucor miehei toward 20:1n-9, 20:5n-3, 22:1n-9 and 22:6n-3 has been determined by comparing the alcoholysis (byn-propanol) of various mixtures of C20 and C22 fatty acids (FFA) or the corresponding ethyl esters (FAEE) inn-heptane. For all the fatty acids examined, the degree of conversion was much higher when using FFA rather than FAEE. When
comparing the experiments with either single FAEE or FAEE mixtures, it was found for all four fatty acids that the degree
of conversion depended on whether the FAEE was alone or together with other fatty acids in the reaction mixture. The lipase
showed a strong specificity toward 20:1n-9, whereas the polyunsaturated fatty acids were much poorer substrates, especially
22:6n-3. The degrees of conversion for the two n-3 fatty acids show a clear preference for 20:5n-3 over 22:6n-3, not only
when present alone but also in the different mixtures examined. The results obtained in the present experiments therefore
suggest that when using the lipase fromR. miehei for enrichment of fish oils with n-3 fatty acids, it should not only be possible to diminish the content of 20:1 and 22:1
present in the outer positions in the triacylglycerols, but also to incorporate relatively more 20:5n-3 than 22:6n-3 into
the triglycerides. 相似文献
5.
Production of triglycerides enriched in long-chain n-3 polyunsaturated fatty acids from fish oil 总被引:1,自引:0,他引:1
Stephen R. Moore Gerald P. McNeill 《Journal of the American Oil Chemists' Society》1996,73(11):1409-1414
Processes that combine enzymic and physical techniques have been studied for concentrating and separating eicosapentaenoic
acid (EPA) and docosahexaenoic acid (DHA) from fish oil.Candida rugosa lipase was used in hydrolysis reactions to concentrate these acids in the glyceride fraction. By controlling the degree of
hydrolysis, two products have been obtained, one enriched in total n-3(∼50%), the other enriched in DHA and depleted in EPA
(DHA∼40%, EPA∼7%). The glyceride fraction from these reactions was recovered by evaporation and converted back to triglycerides
by partial enzymic hydrolysis, followed by enzymic esterification. Both reactions were carried out withRhizomucor miehei lipase. DHA-depleted free fatty acids from aC. rugosa hydrolysis were fractionated to increase the EPA level (∼30%) and re-esterified to triglycerides by reaction with glycerol
andR. miehei. 相似文献
6.
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
7.
Microbial lipase-catalyzed hydrolysis, esterification, and alcoholysis reactions were carried out on acid oils of commerce
such as coconut, soybean, mustard, sunflower, and rice bran for the purpose of making fatty acids and various monohydric alcohol
esters of fatty acids of the acid oils. Neutral glycerides of the acid oils were hydrolyzed byCanadida cylindracea lipase almost completely within 48 h. Acid oils were converted into fatty acid esters of short- and long-chain alcohols like
C4, C8, C10, C12, C16, and C18 in high yields by simultaneous esterification and alcoholysis reactions withMucor miehei lipase as catalyst. Acid oils of commerce can be utilized as raw materials in making fatty acids and fatty acid esters using
lipase-catalyzed methodologies. 相似文献
8.
Matthew J. Hills Irmgard Kiewitt Kumar D. Mukherjee 《Journal of the American Oil Chemists' Society》1990,67(9):561-564
Immobilized lipase preparations from seedlings of rape (Brassica napus L.) andMucor miehei (lipozyme) used as biocatalysts in esterification and hydrolysis reactions discriminate strongly against γ-linolenic and
docosahexaenoic acids/acyl moieties. Utilizing this property, γ-linolenic acid contained in fatty acids of evening primrose
oil has been enriched seven to nine-fold, from 9.5 to almost 85% by selective esterification of the other fatty acids with
butanol. Similarly, docosahexaenoic acid of cod liver oil has been enriched four to five-fold, from 9.4 to 45% by selective
esterification of fatty acids (other than docosahexaenoic acid) with butanol. As long as the reaction is stopped before reaching
equilibrium, very little of either γ-linolenic acid or docosahexaenoic acid are converted to butyl esters, which results in
high yields of these acids in the unesterified fatty acid fraction. 相似文献
9.
Hydroxy fatty acid (HFA) esters of long-chain alcohols, such as hydroxy stearates, have potential applications from lubricants
to cosmetics. These esters were synthesized enzymatically to overcome the problems associated with chemical processes. An
immobilized lipase, Rhizomucor miehei, was employed as catalyst in the esterification reaction between hydroxy-stearic acid as a source of HFA and monohydric fatty
alcohols (C8–C18). The yields of esters were in the range of 82–90% by conducting the reactions at 65±2°C, 2–5 mm Hg pressure, and 10% lipase
concentration. The products were analyzed by infrared spectroscopy, and some of their analytical characteristics were determined. 相似文献
10.
Modification of the fatty acid composition of soy lecithin, principally at its 1-position, was investigated by interchange
reaction with the methyl ester of individual fatty acids and a lipase as the catalyst. The consequent effect on the surface
activity of soy lecithin was also examined. The interchange reaction was carried out by heating a mixture of soy lecithin
and methyl ester of a fatty acid at 60°C for 48 h with 10% (by weight of the reactants) Mucor miehei lipase. The lipase was filtered from the reaction mixture, and the product was isolated by combination of acetone extraction,
which removed the methyl ester fraction, and by preparative thin-layer chromatography separation. The soy lecithin showed
distinct change in its fatty acid composition in the sn-1 position. Capric acid was incorporated by 8.4%, while lauric acid and myristic acid were introduced at 14.1 and 15.7%,
respectively. The linolenic acid percentage was increased by about 10 units. The interfacial tension of soy lecithin changed
significantly after incorporation of various saturated fatty acids. 相似文献
11.
B. K. De T. Chatterjee D. K. Bhattacharyya 《Journal of the American Oil Chemists' Society》1999,76(12):1501-1504
Synthesis of geranyl and citronellyl esters of mixed fatty acids has been investigated by alcoholysis of coconut oil (CNO)
using Rhizomucor miehei lipase. CNO fatty acid esters of geraniol and citronellol have unique mild flavors that can be used in food materials. Both
geraniolysis and citronellolysis of CNO produce flavor esters in good yield. Depending on substrate concentration the molar
yield is more than 50%. The optimized reaction conditions were: pressure, atmospheric; temperature, 50°C; incubation period,
5 h; and Lipozyme, 10% (w/w). 相似文献
12.
Synthesis of triacylglycerol containing conjugated linoleic acid by esterification using two blended lipases 总被引:1,自引:0,他引:1
Tadashiro Hirose Yoshie Yamauchi-Sato Yuri Arai Satoshi Negishi 《Journal of the American Oil Chemists' Society》2006,83(1):35-38
We have developed an efficient esterification for the synthesis of triacylglycerol (TAG) containing conjugated linoleic acids
(CLA) using a blend of two powdered lipases. Two pairs of blended lipases promoted the esterification. Rhizomucor miehei lipase, plus Alcaligenes sp. lipase and Penicillium cammembertii MAG and DAG lipase plus Alcaligenes sp. lipase were used. At the optmal ratio of two lipases, the content of TAG containing CLA (TAG-CLA) in all glycerols reached
82–83% after 47 h using 1 wt% of lipases. With R. miehei lipase plus Alcaligenes sp. lipase, the reaction time to obtain ca. 60% of TAG-CLA was one-third of that needed with R. miehei lipase alone. The optimal ratio of two lipases differed between these two pairs. The optimal ratio was 70–80 wt% of R. miehei lipase in the last stage of the reaction, whereas it was over a wide range of 10–90 wt% for P. camembertii lipase. In the blend of R. miehei lipase plus Alcaligenes sp. lipase, activity remained very high after 10 cycles of esterification (every 47 h) and could be used in the industrial
production of TAG-CLA. 相似文献
13.
Mohamed M. Soumanou Uwe T. Bornscheuer 《European Journal of Lipid Science and Technology》2003,105(11):656-660
Fatty acid alkyl esters were produced from various vegetable oils by transesterification with different alcohols using immobilized lipases. Using n‐hexane as organic solvent, all immobilized lipases tested were found to be active during methanolysis. Highest conversion (97%) was observed with Thermomyces lanuginosa lipase after 24 h. In contrast, this lipase was almost inactive in a solvent‐free reaction medium using methanol or 2‐propanol as alcohol substrates. This could be overcome by a three‐step addition of methanol, which works efficiently for a range of vegetable oils (e.g. cottonseed, peanut, sunflower, palm olein, coconut and palm kernel) using immobilized lipases from Pseudomonas fluorescens (AK lipase) and Rhizomucor miehei (RM lipase). Repeated batch reactions showed that Rhizomucor miehei lipase was very stable over 120 h. AK and RM lipases also showed acceptable conversion levels for cottonseed oil with ethanol, 1‐propanol, 1‐butanol and isobutanol (50‐65% conversion after 24 h) in solvent‐free conditions. Methyl and isopropyl fatty acid esters obtained by enzymatic alcoholysis of natural vegetable oils can find application in biodiesel fuels and cosmetics industry, respectively. 相似文献
14.
Nikolaus Weber Erika Klein Kumar D. Mukherjee 《Journal of the American Oil Chemists' Society》1999,76(11):1297-1300
Palmitic acid hexadecylthioester and other long-chain acyl thioesters have been prepared in high yield (80–85%, purity >98%)
by solvent-free lipase-catalyzed thioesterification of fatty acids with alkanethiols in vacuo. A lipase B preparation from Candida antarctica was more effective than a lipase preparation from Rhizomucor miehei and, particularly, those from papaya latex and porcine pancreas. Lipase-catalyzed transthioesterification of fatty acid methyl
esters with alkanethiols was less effective than thioesterification for the preparation of acyl thioesters. However, in transthioesterification,
a lipase preparation from R. miehei was more effective than a lipase B preparation from C. antarctica. Lipases from papaya latex and porcine pancreas led to moderate conversions to acyl thioesters in both thioesterification
and transthioesterification reactions, whereas only small proportions of thioesters were formed using lipase from Rhizopus arrhizus. Lipases from Chromobacterium viscosum and Candida rugosa were not effective at all. 相似文献
15.
The γ-linolenic acid (Z,Z,Z-6,9,12-octadecatrienoic acid, GLA) present in borage oil free fatty acids was concentrated in esterification reactions that
were catalyzed by several preparations of the acyl-specific lipase ofGeotrichum candidum. In this manner, a 95% recovery of the GLA originally present in borage oil (25% GLA) was obtained as a highly enriched fatty
acid fraction with a GLA content of >70%. Other fatty acids concentrated in this fraction were the monounsaturated fatty acids
with chainlengths of C-20 and longer that were present in the oil. An immobilized preparation ofG. candidum on silica gel also was used for the enrichment of GLA in borage oil. In this instance, a 75% recovery of GLA was obtained,
and the supported lipase was reusable (three cycles) with minimal loss in activity.
Presented in part at the 84th Annual Meeting of the American Oil Chemists’ Society, Anaheim, California, May 1993. 相似文献
16.
O. M. Lai H. M. Ghazali C. L. Chong 《Journal of the American Oil Chemists' Society》1998,75(8):953-959
The physical properties of Pseudomonas and Rhizomucor miehei lipase-catalyzed transesterified blends of palm stearin:palm kernel olein (PS:PKO), ranging from 40% palm stearin to 80%
palm stearin in 10% increments, were analyzed for their slip melting points (SMP), solid fat content (SFC), melting thermograms,
and polymorphic forms. The Pseudomonas lipase caused a greater decrease in SMP (15°C) in the PS:PKO (40:60) blend than the R. miehei lipase (10.5°C). Generally, all transesterified blends had lower SMP than their unreacted blends. Pseudomonas lipase-catalyzed blends at 40:60 and 50:50 ratio also showed complete melting at 37°C and 40°C, respectively, whereas for
the R. miehei lipase-catalyzed 40:60 blend, a residual SFC of 3.9% was observed at 40°C. Randomization of fatty acids by Pseudomonas lipase also led to a greater decrease in SFC than the rearrangement of fatty acids by R. miehei lipase. Differential scanning calorimetry results confirmed this observation. Pseudomonas lipase also successfully changed the polymorphic forms of the unreacted blends from a predominantly β form to that of an
exclusively β′ form. Both β and β′ forms existed in the R. miehei lipase-catalyzed reaction blends, with β′ being the dominant form. 相似文献
17.
Lipase B (GCB) produced by the fungus Geotrichum candidum CMICC 335426 is known for its high specificity towards cis-Δ9 unsaturated fatty acids. The wild-type lipase (not genetically modified) as well as the lipase obtained by heterologous
expression of the corresponding gene in Pichia pastoris (genetically modified) were studied in a process aiming to produce an oil containing very little saturated fatty acids (SAFA).
The approach described in this paper is based on the selective hydrolysis of sunflower oil (12% SAFA) using the G. candidum type B (GCB) lipases. Depending on the lipase input, up to 60% w/w degree of hydrolysis was obtained within 6–8 h. Because
of the high specificity of the GCB lipases (specificity factor ∼30), the level of unsaturates in the free fatty acid fraction
was >99% w/w. In contrast with literature data, no loss of specificity was observed, even at the highest degree of hydrolysis
obtained. Though both GCB lipases are stable at 30°C, the rate of hydrolysis decreased considerably during the process. Product
inhibition as well as time-dependent deactivation (half-life ≈2 h) were shown to be involved. After separation of the oil
phase, the unsaturated free fatty acids were recovered from the mixture by evaporation and reconverted to triglycerides by
enzymatic esterification with glycerol. Because the GCB lipases have a very low efficiency for esterification, this reaction
was carried out with immobilized Rhizomucor miehei lipase. Under continuous removal of the water generated during the process, >95% triglycerides were obtained in less than
24 h. Standard deodorization resulted in an odorless, colorless, and tasteless oil with less than 1% SAFA. 相似文献
18.
Alexander Bilyk Raymond G. Bistline Michael J. Haas Stephen H. Feairheller 《Journal of the American Oil Chemists' Society》1991,68(5):320-323
An investigation of lipases fromRhizomucor miehei,Candida rug osa and porcine pancreas revealed that these enzymes hydrolyzed triglycerides in an organic solvent system. The presence of secondary
amines,i.e., diethylamine,N-methylbutylamine, or the tertiary amine, Methylamine, greatly increased the extent of hydrolysis. The lipolysis of tallow
took place under mild conditions,e.g., room temperature, moderate shaking and within 20 hr. At 45°C, complete hydrolysis of tallow was obtained in 6 hr. Vegetable
oils and a fish oil (cod liver oil) were also hydrolyzed at 20°C byR. miehei lipase in the presence of iV-methylbutylamine for 20 hr. The lipases were recovered for reuse with some loss of activity.
Optimum yields of free fatty acids were obtained by usingR. miehei lipase as catalyst.
Mention of brand or firm names does not constitute an endorsement by the U.S. Department of Agriculture over others of a similar
nature not mentioned. 相似文献
19.
Enzymatic enrichment of conjugated linoleic acid isomers and incorporation into triglycerides 总被引:3,自引:0,他引:3
Gerald P. McNeill Chris Rawlins Anne C. Peilow 《Journal of the American Oil Chemists' Society》1999,76(11):1265-1268
A method was developed for the enrichment of either the cis9,trans11 or the trans10,cis12 isomer of conjugated linoleic acid (CLA) from a synthetic CLA mixture consisting predominantly of these isomers in equal
amounts. Lipases were screened for their ability to selectively esterify one isomer at a significantly greater rate than the
other isomer. An immobilized lipase from Rhizomucor miehei was nonselective, but a lipase from Geotrichum candidum esterified the cis9,trans11 isomer more rapidly than the trans10,cis12 isomer. This selectivity was exploited at the kilogram scale to prepare an ester fraction with a content of 91% cis9,trans11 CLA and an unreacted free fatty acid fraction consisting of 82% trans10,cis12 CLA, based on total CLA content. The components of the reaction mixture were separated by molecular distillation. Each
enriched fraction was then incorporated into palm oil triglycerides by interesterification with the non-selective lipase from
R. miehei. Two triglyceride fats resulted, which were enriched in either cis9,trans11 CLA (26.5% cis9,trans11 and 1.7% trans10,cis12) or trans10,cis12 CLA (3.5% cis9,trans11 and 22.9% trans10,cis12). 相似文献
20.
Douglas G. Hayes Robert Kleiman 《Journal of the American Oil Chemists' Society》1995,72(11):1309-1316
Eight lipases were screened for their ability to synthesize estolides from a mixture that contained lesquerolic (14-hydroxy-11-eicosenoic)
acid and octadecenoic acid. With the exception ofAspergillus niger lipase, all 1,3-specific enzymes (fromRhizopus arrhizus andRhizomucor miehei lipases) were unable to synthesize estolides.Candida rugosa andGeotrichum lipases catalyzed estolide formation at >40% yield, with >80% of the estolide formed being monoestolide from one lesquerolic
and one octadecenoic acyl group:Pseudomonas sp. lipase synthesized estolides at 62% yield, but the product mixture contained significant amounts of monoestolide with
two lesquerolic acyl groups as well as diestolide. ImmobilizedR. miehei lipase was chosen to catalyze the esterification of mono-and polyestolide, derived synthetically from oleic acid, with fatty
alcohols or α,ω-diols. Yields were >95% for fatty alcohol reactions and >60% for diol reactions. In addition, the estolide
linkage remained intact through the course of the esterification process. Esterification of estolides improved the estolide’s
properties—for example, lower viscosity and higher viscosity index—but slightly raised the melting point. Estolides and, particularly,
estolide esters may be suitable as lubricants or lubricant additives. 相似文献