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1.
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
2.
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
3.
Yanis Caro Fabrice Turon Pierre Villeneuve Michel Pina Jean Graille 《European Journal of Lipid Science and Technology》2004,106(8):503-512
We have examined the possibility of producing analogs of medium‐chain triglycerides (MCT) from copra oil, i.e. a triacylglycerol mixture with a high content of medium‐chain fatty acid moieties (C6–C10). A two‐step enzymatic process was used in which copra triacylglycerols were first split with papain lipase by alcoholysis with an alkyl alcohol and then subjected to interesterification with the alkyl esters recovered using papain lipase. Effects of temperature, water activity content, substrate ratio, biocatalyst amount, and alcohol chain length were also investigated. On the one hand, the sn‐3 stereoselectivity of the lipase in the alcoholysis of copra oil with butanol has permitted a direct enrichment of caproic, caprylic and capric moieties in the synthesized butyl esters. Thus, in the batch reactor, the reaction led to about 31% conversion of the oil after 24 h, and the content of C6–C10 acids in the synthesized esters increased from about 16% in the starting oil to almost 42%. A similar enzymatic alcoholysis in a packed‐bed column bioreactor gave 31% conversion of the oil after 120 min of reactor residence time. The reaction was also very selective because the C6–C10 fatty acyl groups represented about half of the newly formed butyl esters, whereas they accounted for only 16% of total fatty acids in the starting oil. On the other hand, the transesterification of the alkyl esters recovered (highly enriched in C6–C10 fatty acyl groups) with native copra oil directly led to an increase in the content of MCT in the oil, from 18 mol‐% at the beginning of the reaction to 61 mol‐% of MCT after a time period of 72 h in the batch reactor. 相似文献
4.
Candida cylindracea lipase (SIGMA) was tested against triglycerides (TG) and wax esters (WE) of marine origin as substrates. Under the same conditions, wax esters were hydrolysed at a lower rate than the triglycerides. The C14 to C18 saturated and monounsaturated fatty acids were preferentially hydrolysed whereas the longer chain monoenes (20:1 and 22:1) and particularly the polyunsaturated fatty acids (18:4,20:5 and 22:6) were resistant to the hydrolysis in triglycerides as well as in wax esters. No specificity was demonstrated for the fatty alcohols in the wax esters. 相似文献
5.
Medium-chain fatty acid-rich glycerides by chemical and lipase-catalyzed polyester-monoester interchange reaction 总被引:4,自引:0,他引:4
Medium-chain triglycerides (MCT) that contain caprylic acid (C8:0) and capric acid (C10:0) have immense medicinal and nutritional importance. Coconut oil can be used as a starting raw material for the production
of MCT. The process, based on the interchange reaction between triglycerides and methyl esters of medium-chain fatty acids
by chemical catalyst (sodium methoxide) or lipase (Mucor miehei) catalyst, appears to be technically feasible. Coconut oils with 25–28.3% (w/w) and 22.1–25% (w/w) medium-chain fatty acids
have been obtained by chemical and lipase-catalyzed interchange reactions. Coconut olein has also been modified with C8:0 and C10:0 fatty acids, individually as well as with their mixtures, by chemical and lipase-catalyzed interchange reactions. Coconut
olein is a better raw material than coconut oil for production of mediumchain fatty acid-rich triglyceride products by both
chemical and lipase-catalyzed processes. 相似文献
6.
Robert R. Klein Gregory King Robert A. Moreau Gerald P. McNeill Pierre Villeneuve Michael J. Haas 《Journal of the American Oil Chemists' Society》1997,74(11):1401-1407
The fatty acid specificity and pH dependence of triacylglycerol hydrolysis by the Rhizopus delemar lipase acylbinding site mutant Val206Thr+Phe95Asp (Val, valine; Thr, threonine; Phe, phenylalanine; Asp, aspartic acid) were
characterized. The activity of the double mutant prolipase was reduced by as much as 10-fold, compared to the wild-type prolipase.
However, the fatty acid specificity profile of the enzyme was markedly sharpened and was dependent on the pH of the substrate
emulsion. At neutral pH, strong preference (10-fold or greater) for hydrolysis of triacylglycerols of medium-chainlength fatty
acids (C8:0 to C14:0) was displayed by the variant prolipase, with no hydrolysis of triacylglycerols of short-chain fatty acids (C4:0 to C6:0) and little activity manifested toward fatty acids with 16 or more carbons. At acidic pH values, the fatty acid selectivity
profile of the double mutant prolipase expanded to include short-chain triacylglycerols (C4:0, C6:0). When assayed against a triacylglycerol mixture of tributyrin, tricaprylin and triolein, the Val206Thr+Phe95Asp prolipase
displayed a high selectivity for caprylic acid and released this fatty acid at least 25-fold more efficiently than the others
present in the substrate mixture. When presented a mixture of nine fatty acid methyl esters, the wild-type prolipase showed
a broad substrate specificity profile, hydrolyzing the various methyl esters to a similar extent. Contrastingly, the double
mutant prolipase displayed a narrowed substrate specificity profile, hydrolyzing caprylic methyl ester at nearly wild-type
levels, while its activity against the other methyl esters examined was 2.5- to 5-fold lower then that observed for the wild-type
enzyme. 相似文献
7.
A total of fifteen saturated fatty acid esters were newly identified from the secretions of an unidentified Anaulaciulus sp. (Julida: Julidae). The fatty acid components of the esters were composed of normal chain acids (from C10 to C14) and of branched chain acids (from iso-C12 to iso-C15 and anteiso-C15). The alcohol moieties were all composed of normal chain alcohols varying from n-butanol to n-octanol. The most abundant component found in the total esters was n-hexyl laurate (64.7%). Novel compounds identified from the millipede secretion extracts include six branched iso- and anteiso-fatty
esters, an odd-numbered C11-fatty acid ester, a C13-fatty acid ester, and a C7-alcohol ester, all of which were previously undescribed natural products. In addition, a characteristic mixture of benzoquinones,
such as 2-methyl-1,4-benzoquinone, 2-methoxy-3-methyl-1,4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, 2-methoxy-6-methyl-1,4-benzoquinone,
and 2,3-dimethoxy-5-methyl-1,4-benzoquinone were identified from the secretions, together with trace amounts of 1,4-benzoquinone. 相似文献
8.
Roxana Irimescu Kiyomi Furihata Kazuhiko Hata Yugo Iwasaki Tsuneo Yamane 《Journal of the American Oil Chemists' Society》2001,78(7):743-748
Symmetrically structured triacylglycerols (TG) rich in docosahexaenoic acid (DHA) with caprylic acid (CA) at the outer positions
were synthesized enzymatically form bonito oil in a two-step process: (i) ethanolysis of bonito oil TG to 2-monoacylglycerols
(2-MG) and fatty acid ethyl esters, and (ii) reesterification of 2-MG with ethyl caprylate. Ethanolysis catalyzed by immobilized
Candida antarctica lipase (Novozym 435) yielded 92.5% 2-MG with 43.5% DHA content in 2 h. The 2-MG formed were reesterified with ethyl caprylate
by immobilized Rhizomucor miehei lipase (Lipozyme IM) to give structured TG with 44.9% DHA content [based on fatty acid composition with caprylic acid (CA)
excluded] in 1 h. The final structured lipids comprised 85.3% TG with two CA residues and one original fatty acid residue,
13% TG with one CA residue and two original fatty acid residues, and 1.7% tricaprylolglycerol (weight percent). The amount
of TG with two CA residues and one C22 residue (22∶6=DHA, 22∶5, and 22∶4) was 51 wt%. The 1,3-dicapryloyl-2-docosahexaenoylglycerol to 1,2(2,3)-dicapryloyl-3 (1)-docosahexaenoylglycerol
ratio (based on high-performance liquid chromatography peak area percentages) was greater than 50∶1. The recovery of TG as
structured lipids after silica gel column purification was approximately 71%. Ethyl esters and 2-MG formed at 2 h of ethanolysis
could be used to determine the positional distribution of fatty acids in the intial TG owing to the high 1,3-regiospecificity
of Novozym 435 and the reduced acyl migration in the system. 相似文献
9.
Thomas K. Miwa 《Journal of the American Oil Chemists' Society》1971,48(6):259-264
HCl-catalyzed ethanolysis followed by saponification readily surmounts the resistance of long chain wax esters to direct hydrolysis
by alkali. Additionally, choosing ethyl instead of methyl esters allows baseline separations between long-chain alcohols and
corresponding esters in gas liquid chromatographic (GLC) analysis of total alcohol and acid components before saponification.
Liquid wax esters were analyzed on a temperature-programmed 3% OV-1 silicone column. Geographical and genetic effects on the
variability of jojoba oil composition were investigated with five different seed samples. Major constituents in jojoba seed
oil from shrubs in the Arizona deserts, as indicated by GLC analyses of oil, ethanolysis product, isolated fatty alcohols
and methyl esters of isolated fatty acids, were C40 wax ester 30%, C42 wax ester 50% and C44 wax ester 10%; octadecenoic acid 6%; eicosenoic acid 35%, docosenoic acid 7%, eicosenol 22%, docosenol 21% and tetracosenol
4%. Oil from smaller leaved prostrate plants growing along California’s oceanside showed a slight tendency toward higher molecular
size than oils from the California desert and Arizona specimens. The wax esters are made up of a dispro-portionately large
amount of docosenyl eicosenoate and are not a random combination of constituent acids and alcohols.Lunaria annua synthetic wax ester oil was used as a model for evaluating the analytical procedures.
Presented at the AOCS Meeting, Chicago, September 1970
No. Utiliz, Res. Dev. Div., ARS, USDA. 相似文献
10.
Zi-Long Deng Jian-Ping Yuan Yan Zhang Xiao-Ming Xu Chou-Fei Wu Juan Peng Jiang-Hai Wang 《Journal of the American Oil Chemists' Society》2013,90(10):1495-1502
Free and esterified ergosterols are detected almost solely in fungi and are often employed as a biomarker of living fungi. In this work, the fatty acid composition and δ13C values of major fatty acids in triglycerides and ergosteryl esters from the fungus Ganoderma lucidum were analyzed by gas chromatography–mass spectrometer and gas chromatography–isotopic ratio mass spectrometer, respectively. The results showed that the fatty acid profiles varied in triglycerides and ergosteryl esters. The percentage of saturated fatty acids in ergosteryl esters was remarkably higher than that in triglycerides, where C18:1Δ9c was the predominant fatty acid and constituted 61.26 % of the total fatty acids. In contrast, C16:0 was the predominant fatty acid and constituted 71.88 % of the total fatty acids in ergosteryl esters. The study suggests that, after fungal death, free ergosterols in the cell membrane of the dead fungus were esterified with preferentially saturated fatty acids, mainly C16:0, from triglycerides and then stored in lipid particles for a longer period while free ergosterol markedly decreased. The δ13C values of C16:0, C18:0, C18:1 and C18:2 in ergosteryl esters exhibit a pronounced depletion in 13C compared with that in triglycerides within the range of ?1.3 to ?0.9 ‰, supporting the above inference. It is again suggested that free ergosterol in the cell membrane should be used as an indicator of living fungi, and ergosteryl esters in the lipid particles should not be included in the measurement of living fungal biomass. 相似文献
11.
Methyl sterculate was rearranged by use of 0.5% of rhodium catalyst to isomeric conjugated diene fatty acid methyl esters
containing both methylene-and methyl-branched isomers. The rearanged products were hydrogenated directly to saturated, methyl-substituted,
branched-chain fatty acid methyl esters with the methyl substituent at one of the positions formerly occupied by the cyclopropenoid
ring. The crude branched-chain fatty acids from these esters were purified by recrystallization from a mixed solvent of ethanol
and water (80:20, v/v) and flash distillation; the product contained about 90% of branched-chain fatty acids (C19:80%, C18:10%). Esters of the branched-chain fatty acid were prepared with 2-ethylhexyl alcohol or trimethylolpropane, and the characteristic
properties of these esters were investigated. The branched-chain fatty esters appear to have potential utility in lubricants;
other uses may be possible.
Presented at the AOCS meeting in New Orleans, May 1981. 相似文献
12.
Mangesh G. Kulkarni Sudhirprakash B. Sawant 《European Journal of Lipid Science and Technology》2003,105(5):214-218
Esters of castor oil and hydrogenated castor oil were prepared with C6, C12, C16, C18 fatty acids, using tetra‐n‐butyl titanate as a catalyst and n‐butyl benzene as a water entrainer. Physical properties such as melting point, refractive index, viscosity, and specific gravity of these esters were measured. Slip melting points of the esters were very low in both cases. These esters did not crystallize even at low temperature. The highest slip melting point obtained was 21 °C with stearoyl hydrogenated castor oil ester and lowest slip melting point obtained was —6 °C with hexanoyl castor oil ester. 相似文献
13.
Kyoichi Osada Koretaro Takahashi Mutsuo Hatano 《Journal of the American Oil Chemists' Society》1990,67(12):921-922
The degree of glyceride syntheses by lipase TOYO (Chromobacterium viscosum) and lipase OF (Candida cylindracea) using individual free fatty acids C18∶1, C18∶2, C18∶3, C18∶4, C20∶4, C20∶5 and C22∶6 were compared. Lipase TOYO incorporated each of the fatty acids into glycerol at levels of greater than 89%. Lipase OF incorporated
most of the fatty acids at levels above 70% (docosahexaenoic acid incorporation was 63%). It was concluded that these two
lipases are feasible for producing glycerides from unsaturated fatty acids. 相似文献
14.
Studies on the enzymatic synthesis of lipophilic derivatives of natural antioxidants 总被引:7,自引:0,他引:7
H. Stamatis V. Sereti F. N. Kolisis 《Journal of the American Oil Chemists' Society》1999,76(12):1505-1510
The esterification of some natural antioxidants such as cinnamic acid derivatives and ascorbic acid in non-aqueous media,
catalyzed by immobilized lipases from Candida antarctica and Rhizomucor miehei, was investigated. The alcohol chain length affected the rate of esterification of cinnamic acids by both lipases. Higher
reaction rates were observed when the esterification was carried out with medium- or long-chain alcohols. The rate also depended
on aromatic acid structure. The reactivity of the carboxylic function of the cinnamic acids was affected by electron-donating
substituents in the aromatic ring. Higher yields were observed for the esterification of p-hydroxyphenylacetic acid (97%) catalyzed by C. antarctica lipase and for the esterification of cinnamic acid (59%) catalyzed by R. miehei lipase. Candida antarctica lipase was more suitable for producing ascorbic acid fatty esters, catalyzing with a relatively high yield (up to 65% within
24 h) the regioselective esterification of ascorbic acid with various fatty acids in 2-methyl-2-propanol. The reaction rate
and yield depended on the fatty acid chain length and on the molar ratio of reactants. All ascorbic acid fatty esters produced
by this procedure exhibited a significant antioxidant activity in a micellar substrate composed of linoleic acid. 相似文献
15.
An immobilized sn-1,3-specific lipase from Rhizomucor miehei (IM 60) was used to catalyze the interesterification of tristearin (C18:0) and tricaprin (C10:0) to produce low-calorie structured lipids (SL). Acceptable product yields were obtained from a 1:1 mole ratio of both triacylglycerols
with 10% (w/w of reactants) of IM 60 in 3 mL hexane. The SL molecular species, based on total carbon number, were 44.2% C41 and 40.5% C49, with 3.8 and 11.5% unreacted tristearin C57 and tricaprin C27, respectively, remaining in the product mixture. The best yield of C41 species (44.3%) was obtained with zero added water. Tricaprylin (C8:0) was also successfully interesterified with tristearin in good yields at 1:1 mole ratio. Products were analyzed by reverse-phase
high-performance liquid chromatography with an evaporative light-scattering detector. Reaction parameters, such as substrate
mole ratio, enzyme load, time course, added water, reaction media, and enzyme reuse, were also investigated. Hydrolysis by
pancreatic lipase revealed the specific fatty acids present at the sn-1,3 positions of SL.
Biocatalysis Symposium Paper, presented at the AOCS Annual Meeting & Expo, Seattle, Washington. May 11–14, 1997. 相似文献
16.
Chemo-enzymatic synthesis of disaccharide fatty acid esters 总被引:3,自引:0,他引:3
Douglas B. Sarney Herwig Kapeller Guiseppe Fregapane Evgeny N. Vulfson 《Journal of the American Oil Chemists' Society》1994,71(7):711-714
A novel enzymatic method for the synthesis of disaccharide fatty acid esters was developed with immobilizedMucor miehei lipase (Lipozyme IM-60; Novo Nordisk, Bagsvaerd, Denmark) as a catalyst. A range of lactose and maltose monoesters was prepared
in overall yields of 48–77% from the corresponding sugar acetals and fatty acids. 相似文献
17.
Metathesis of Unsaturated Fatty Acid Esters – a Simple Approach to Long-Chained Dicarboxylic Acids Long-chained, symmetric unsaturated C18-, C20- und C26-dicarboxylic acid esters are easily accessible from natural fatty acid esters by metathesis in a two-step procedure. In the first step unsaturated fatty acid esters are cleaved by metathesis with ethylene. Pure oleic acid ester or fatty acid methylesters, produced from high-oleic sunflower oil or from rapeseed oil by transesterification with methanol, are converted to 1-decene and 9-decenoic acid methylester. From erucic acid methylester 1-decene and 13-tetradecenoic acid methylester are achieved. Using our newly developed high efficient catalytic system B2O3-Re2O7/Al2O3-SiO2 + SnBu4 conversion rates of 86 – 96% are obtained and the terminally unsaturated fatty acid esters are isolated in yields of 61 – 83%. In the second step 9-decenoic and 13-tetradecenoic acid methylester as well as 10-undecenoic methylester, which is commercially obtained by pyrolysis of ricinoleic acid ester, are converted to 9-octadecenedioic-, 13-hexacosenedioic- and 10-eicosenedioic acid dimethylester, by which process ethylene is eliminated. The conversion rates are 89 – 99% and the dicarboxylic acid dimethylesters are isolated in yields of 77 – 84%. 相似文献
18.
The esterification of five medium- and long-chain acetylenic alcohols (2-nonyn-1-ol, 10-undecyn-1-ol, 6-octadecyn-1-ol, 9-octadecyn-1-ol,
and 13-docosyn-1-ol), seven olefinic alcohols (cis-3-nonen-1-ol, 10-undecen-1-ol, cis-6-octadecen-1-ol, cis-9-octadecen-1-ol, trans-9-octadecen-1-ol, trans-9, trans-11-octadecadien-1-ol, cis-9, cis-12-octadecadien-1-ol), and four short-chain unsaturated alcohols (allyl alcohol, 3-butyn-1-ol, 3-pentyn-1-ol, and cis-2-penten-1-ol) with pentanoic or stearic acid in the presence of various lipase preparations was studied. With the exception
of 2-nonyn-1-ol, where Lipase AY-30 (Candida rugosa) was used as the biocatalyst, the esterification of C11, C18, and C22 acetylenic alcohols with pentanoic acid appeared to be generally unaffected by the presence of an acetylenic bond in the
alcohol as relatively high yields of the corresponding esters (78–97%) were obtained. However, medium- and long-chain olefinic
alcohols were discriminated by Lipase AY-30, Lipolase 100T (Rhizomucor miehei), and especially by porcine pancreatic lipase (PPL), when esterification was conducted with pentanoic acid. Esterification
of medium-and long-chain acetylenic or olefinic alcohols with a long-chain fatty acid, stearic acid, was very efficient except
when Lipase AY-30 and Lipolase 100T were used. Short-chain unsaturated alcohols were much more readily discriminated. 3-Pentyn-1-ol
and 3-butyn-1-ol were difficult (<5% yield) to esterify with pentanoic or stearic acid in the presence of Lipase AY-30 and
PPL, respectively. Very low yields (<26%) of esters were produced when 3-butyn-1-ol and 3-pentyn-1-ol were reacted with pentanoic
or stearic acid, when catalyzed by lipase from Candida cylindracea, No reaction took place between 3-butyn-1-ol and stearic acid in the presence of Lipase AY-30. Esterification of short-chain
acetylenic and olefinic alcohols was most efficiently achieved with Lipolase 100T (Rhizomucor miehei), Lipozyme IM20 (Rh. miehei), or Novozyme 435 (Candida antarctica) as the biocatalyst. 相似文献
19.
Enzymatic synthesis of fatty alcohol esters by alcoholysis 总被引:5,自引:0,他引:5
B. K. De D. K. Bhattacharyya C. Bandhu 《Journal of the American Oil Chemists' Society》1999,76(4):451-453
Lipase-catalyzed conversions of some minor oils and fats like mowrah (Madhuca latifolia), mango (Mangifera indica) kernel, and sal (Shorea robusta) fats into low, medium, and high molecular weight alcohol esters have been investigated. In solvent-free medium, alcoholysis
of the above-mentioned fats with 10% (w/w) Mucor miehei lipase produced alcohol esters in good yield. The percentage molar conversions of C4, C8, C10, C12, C14, C16, C18, and C18:1 alcohols into corresponding alcohol esters ranged from 86.8 to 99.2, while the percentage molar conversions on the basis
of oil were in the range of 108.0 to 123.5. 相似文献
20.
A group of unusual triglycerides, in which one of the acyl groups is a vicinal dihydroxy acid with one of the hydroxyl groups
acetylated, has been isolated fromCardamine impatiens L. (Cruciferae) seed oil. Hydrolysis of these triglycerides with castor bean lipase facilitated isolation and identification
of a mixture of C18, C20, C22, and C24 hydroxy acetoxy fatty acids. Pancreatic lipase hydrolysis data revealed that these monoacetylated dihydroxy acid residues
are esterified exclusively with one of the α-positions of the glycerol moiety. The remaining acyl groups are comprised of
ordinary C18 unsaturated acids (which occupy 98% of the β-position), palmitic acid, and C20, C22, and C24 monoenoic fatty acids.
No. Utiliz. Res. Dev. Div., ARS, USDA. 相似文献