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1.
Gökhan Kildiran Sevil Özgül Yücel Selma Türkay 《Journal of the American Oil Chemists' Society》1996,73(2):225-228
In-situ alcoholysis of soybean oil with methanol, ethanol,n-propanol, andn-butanol was investigated, as well as the extraction of the oil with these solvents, to explain the progress ofin-situ alcoholysis and to determine the parameters that affect this reaction. Because methanol is a poor solvent for soybean oil,
the amount of oil dissolved in methanol and converted to methyl esters was low afterin-situ alcoholysis. Ethyl, propyl, and butyl esters of soybean fatty acids could be obtained in high yields fromin-situ alcoholysis of soybean oil with these alcohols.In-situ alcoholysis proceeded through dissolution and alcoholysis of triglycerides successively, and the overall reaction rate was
determined by the extraction and alcoholysis rates. The parameters, affecting yield and purity of the product esters, were
mainly those that favor extraction rate. 相似文献
2.
Sirirung Wongsakul Poonsuk Prasertsan Uwe T. Bornscheuer Aran H‐Kittikun 《European Journal of Lipid Science and Technology》2003,105(2):68-73
Commercial immobilized lipases were used for the synthesis of 2‐monoglycerides (2‐MG) by alcoholysis of palm and tuna oils with ethanol in organic solvents. Several parameters were studied, i.e., the type of immobilized lipases, water activity, type of solvents and temperatures. The optimum conditions for alcoholysis of tuna oil were at a water activity of 0.43 and a temperature of 60 °C in methyl‐tert‐butyl ether for ~12 h. Although immobilized lipase preparations from Pseudomonas sp. and Candida antarctica fraction B are not 1, 3‐regiospecific enzymes, they were considered to be more suitable for the production of 2‐MG by the alcoholysis of tuna oil than the 1, 3‐regiospecific lipases (Lipozyme RM IM from Rhizomucor miehei and lipase D from Rhizopus delemar). With Pseudomonas sp. lipase a yield of up to 81% 2‐MG containing 80% PUFA (poly‐unsaturated fatty acids) from tuna oil was achieved. The optimum conditions for alcoholysis of palm oil were similar as these of tuna oil alcoholysis. However, lipase D immobilized on Accurel EP100 was used as catalyst at 40 °C with shorter reaction times (<12 h). This lead to a yield of ~60% 2‐MG containing 55.0‐55.7% oleic acid and 18.7‐21.0% linoleic acid. 相似文献
3.
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
4.
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
5.
Siegfried K. F. Peter Ruth Ganswindt Hans-Peter Neuner Eckhard Weidner 《European Journal of Lipid Science and Technology》2002,104(6):324-330
Synthesis of fatty acid esters by alcoholysis, especially methanolysis of triacylglycerols was investigated using metal salts of amino acids as catalysts. The methanol to oil molar ratio was 6:1. It could be shown that salts containing a quaternary amino or a highly basic group as e.g. a guanidino group have catalytic activity in alcoholysis. Some of these salts are insoluble in monovalent alcohols, glycerol, and fatty acids esters and are therefore suitable catalysts for heterogeneously catalysed alcoholysis. Zinc salts of arginine, carnitine or histidine are among others suited for industrial use. These catalysts are also suitable for heterogeneously catalysed interesterification. 相似文献
6.
Lipase catalyzed alcoholysis of sunflower oil 总被引:9,自引:0,他引:9
Martin Mittelbach 《Journal of the American Oil Chemists' Society》1990,67(3):168-170
Lipase-catalyzed alcoholysis of sunflower oil under anhydrous conditions was examined. Lipases fromPseudomonas fluorescens and 2 immobilized enzymes fromMucor miehei and aCandida sp. gave sufficient conversion with petroleum ether as the solvent, even when methanol and ethanol were used. The overall content
of tri-, di- and monoglycerides, as well as the corresponding alkyl esters, was measured. BecausePseudomonas lipase led to almost quantitative esterification, further studies were carried out with that enzyme varying the amounts of
enzyme or the alcohols. Acceptable conversions were achieved even without solvent. Reaction rates of alcoholysis with 5 homologous
alcohols, with or without the addition of water, were measured, and in all cases the reaction rates increased with higher
chain length of the alcohol. In the case of methanol the highest rate was obtained without any addition of water, but a significantly
higher rate was observed with 96% ethanol as opposed to absolute ethanol. The main advantages of lipasecatalyzed, nonaqueous
alcoholysis as compared to classical procedures are the mild reaction conditions, the isolation of glycerin without further
purification and without the formation of chemical waste, and the ability of lipases to catalyze the esterification of free
fatty acids. 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.
Yuji Shimada Kazuaki Maruyama Akio Sugihara Takashi Baba Sadao Komemushi Shigeru Moriyama Yoshio Tominaga 《Journal of the American Oil Chemists' Society》1998,75(11):1565-1571
Ethyl docosahexaenoate (E-DHA) is efficiently enriched by the selective alcoholysis of ethyl esters originating from tuna
oil with lauryl alcohol using immobilized lipase. Alcoholysis of ethyl esters by immobilized Rhizopus delemar lipase raised the E-DHA content in the unreacted ethyl ester fraction from 23 to 49 mol% in 90% yield. However, the content
of ethyl eicosapentaenoate (E-EPA) was higher than the initial content. Hence we attempted to screen for a suitable lipase
to decrease the E-EPA content, and chose Rhizomucor miehei lipase. Several factors affecting the alcoholysis of ethyl esters were investigated, and the reaction conditions were determined.
When alcoholysis was performed at 30°C with shaking in a mixture containing ethyl esters/lauryl alcohol (1:3, mol/mol) and
4 wt% of the immobilized R. miehei lipase, the E-DHA content in the ethyl ester fraction was increased and the E-EPA content was decreased. By alcoholyzing
ethyl esters in which the E-DHA content was 45 mol% (E-tuna-45) for 26 h, the E-DHA content was increased to 74 mol% in 71%
yield and the E-EPA content was decreased from 12 to 6.2 mol%. To investigate the stability of the immobilized lipase, batch
reactions were carried out continually by replacing the reaction mixture with fresh E-tuna-45/lauryl alcohol (1:3, mol/mol)
every 24 h. The decrease in the alcoholysis extent was only 17% even after 100 cycles of reaction. It was found that increasing
the proportion of lauryl alcohol increased the conversion of E-EPA to lauryl-EPA. When an ethyl ester mixture in which the
E-DHA content was 60 mol% (E-tuna-60) was alcoholyzed for 24 h with 7 molar equivalents of lauryl alcohol, the E-DHA content
was raised to 93 mol% with 74% yield and the E-EPA content was reduced from 8.6 to 2.9 mol%. 相似文献
9.
Mohamed M. Soumanou Uwe T. Bornscheuer Rolf D. Schmid 《Journal of the American Oil Chemists' Society》1998,75(6):703-710
Structured triacylglycerides with medium-chain fatty acids (caprylic acid) in sn1- and sn3-positions and a long-chain unsaturated fatty acid (oleic or linoleic acid) in the sn2-position of glycerol (MLM) were synthesized by lipase catalysis in a two-step process. First, pure 2-monoacylglycerides
(2-MG) were synthesized by alcoholysis of triacylglycerides (triolein, trilinolein, or peanut oil) in organic solvents with
1,3-regiospecific lipases (from Rhizomucor miehei, Rhizopus delemar, and Rhizopus javanicus). The 2-MG were purified by crystallization and obtained in up to 71.8% yield. These 2-MG were esterified in a second reaction
with caprylic acid in n-hexane to form almost pure MLM. For 2-MG obtained from peanut oil, the final product contained more than 90% caprylic acid
in the sn1- and sn3-positions, whereas the sn2-position was composed of 98.5% unsaturated long-chain fatty acids. Reaction conditions for both steps were optimized with
respect to source and immobilization of lipase, water activity, and solvent. 相似文献
10.
Enzymatic Synthesis of Biodiesel from Transesterification Reactions of Vegetable Oils and Short Chain Alcohols 总被引:1,自引:0,他引:1
Rafael Costa Rodrigues Giandra Volpato Keiko Wada Marco Antônio Záchia Ayub 《Journal of the American Oil Chemists' Society》2008,85(10):925-930
Biodiesel synthesis by alcoholysis of three vegetable oils (soybean, sunflower and rice bran) catalyzed by three commercial
lipases (Novozym 435, Lipozyme TL-IM and Lipozyme RM-IM), and the optimization of the enzymes stability over repeated batches
is described. The effects of the molar ratio of alcohol to oil and the reaction temperature with methanol, ethanol, propanol
and butanol were also studied. All three enzymes displayed similar reaction kinetics with all three oils and no significant
differences were observed. However, each lipase displayed the highest alcoholysis activity with a different alcohol. Novozym
435 presented higher activity in methanolysis, at a 5:1 methanol:oil molar ratio; Lipozyme TL-IM presented higher activity
in ethanolysis, at a 7:1 ethanol:oil molar ratio; and Lipozyme RM-IM presented higher activity in butanolysis, at a 9:1 butanol:oil
molar ratio. The optimal temperature was in the range of 30–35 °C for all lipases. The assessment of enzyme stability over
repeated batches was carried out by washing the immobilized enzymes with different solvents (n-hexane, water, ethanol, or propanol) after each batch. When washing with n-hexane, approximately 90% of the enzyme activity remained after seven synthesis cycles. 相似文献
11.
Lipase biocatalysis in the production of esters 总被引:2,自引:0,他引:2
Y. -Y. Linko M. Lämsä A. Huhtala O. Rantanen 《Journal of the American Oil Chemists' Society》1995,72(11):1293-1299
Lipase biocatalysis was investigated as a tool for the production of butyl oleate and rapeseed oil 2-ethyl-1-hexyl ester by
esterification and transesterification, respectively. We screened 25 commercially available lipases and found that butyl oleate
was produced at high yields from oleic acid and 1-butanol by lipases fromCandida rugosa, Chromobacterium viscosum, Rhizomucor miehei, and Pseudomonas fluorescens. The initial water content of the system, lipase quantity, and the molar ratio of 1-butanol to oleic acid were important
factors in influencing the ester yield. In general, no ester was formed without the addition of water. The exception wasCh. viscosum lipase, which yielded 98% of ester in 12 h with 1-butanol excess without additional water. The addition of 3.2% water increased
the initial rate of reaction. With an oleic acid excess and only 0.3% lipase,C. rugosa andR. miehei lipases yielded 94 and 100% esters with initial water contents of 3.2 and 14%, respectively. Lipase-catalyzed alcoholysis
of low-erucic acid rapeseed oil and 2-ethyl-1-hexanol without additional organic solvent also was studied in stirred batch
reactors. In this case,C. rugosa lipase was the best biocatalyst with an optimal 2-ethyl-1-hexanol to rapeseed oil molar ratio of 2.8, a minimum of 1.0% added
water, and 37°C. An increase in temperature up to 55°C increased the rate of reaction but did not affect the final ester yield.
The enzyme was inactivated at 60°C. Under optimal conditions, the ester yield increased from 88% in 7 h to nearly complete
conversion in 1 h when the lipase content was increased from 0.3 to 14.6%. In a 2-kg small pilot scale, up to 90% conversion
(97% of theoretical) was obtained in 8 h at 37°C with 3.4% lipase in the presence of Amberlite XAD-7 resin with 3% added water. 相似文献
12.
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
13.
Pieter Levecque DavidW. Gammon Henok Hadgu Kinfe Pierre Jacobs Dirk De Vos Bert Sels 《Advanced Synthesis \u0026amp; Catalysis》2008,350(10):1557-1568
Venturello’s phosphotungstate complex and titanium(IV) isopropoxide [Ti(O‐i‐Pr)4] were successfully used as catalysts for the epoxidation‐alcoholysis of glycals using hydrogen peroxide [H2O2]. Reaction substrates included a range of variously protected glycals and different alcohols were used as solvents. Ti(O‐i‐Pr)4 was only effective in methanol as solvent, but gave methyl glycosides in high yields and high selectivities. The Venturello complex proved to be a very versatile and efficient catalyst. Apart from epoxidation‐alcoholysis in alcoholic solvents it also showed activity in biphasic conditions to allow for glycosylation of long‐chain alcohols and was very effective in the stereoselective dihydroxylation of benzylated glucal. 相似文献
14.
Rudolf Brenneis Burkhard Baeck Gerd Kley 《European Journal of Lipid Science and Technology》2004,106(12):809-814
Commercial native lipase A from Candida antarctica was used to produce alkyl esters through the alcoholysis of (waste) fats with 2‐ethyl‐1‐hexanol. The process was carried out in batch stirred tank reactors (from 100 mL up to 3000 L). The content of alkyl esters in reaction mixtures was determined by gradient HPLC using an evaporative light scattering detector and the reaction progress was controlled by determining the ratio of the palmitic acid ester peak area to the oleic acid ester peak area in HPLC chromatograms. The results show that alcoholysis is the favoured reaction in presence of excess water and water‐insoluble alcohols in comparison with hydrolysis (fatty acid content <5%). The optimum amount of water for the alcoholysis was found to be 80–100% of the amount of fat. In the presence of low quantities of water both alcoholysis and hydrolysis are slow. Conversion rate increases with increasing temperature to 65–70 °C. Based on these results a large‐scale test to produce 3000 L of alkyl ester (to be used as lubricant coolant) was carried out. The experiments have proved that alcoholysis is completed after about 7–10 h depending on temperature. 相似文献
15.
Mohamed M. Soumanou Sebastien T. Djenontin Fidele P. Tchobo Dominique C. K. Sohounhloue Uwe T. Bornscheuer 《Lipid Technology》2012,24(7):158-160
Biodiesel as fatty acid alkylesters has become attractive because of its environmental benefits. A non‐edible oil as starting material for biodiesel production appears desirable and does not compromise the edible oils used mainly for food and feed. The present article discusses the enzymatic alcoholysis of crude Jatropha curcas oil in solvent free medium for the production of valuable fatty acid alkyl esters for use as biodiesel. Among various microbial lipases commonly tested in the literature, the highest initial rate (>18 μmol h–1 mg–1) with different alcohols was observed with immobilized lipase from Pseudomonas cepacia, but the activity depends on the amount of water. The best conversion (93%) to produce ethyl esters was achieved with lipase immobilized on the polypropylene carrier Accurel 1282 after 16 h at low enzyme concentration (3% w/w). Moreover, the transesterification could be conducted for at least 160 h during 10 batch runs without significant loss of activity. This reduces the costs for immobilized lipase and can thus make the enzymatic biodiesel production commercially more viable, especially starting from a non‐edible plant oil. 相似文献
16.
Hung‐Min Chang Hui‐Fen Liao Chin‐Chia Lee Chwen‐Jen Shieh 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(3):307-312
The ability of immobilized lipase from Candida antarctica (Novozym 435) to catalyze the alcoholysis of canola oil and methanol was investigated. Response surface methodology (RSM) and five–level–five–factor central composite rotatable design (CCRD) were employed to evaluate the effects of synthesis parameters, such as reaction time, temperature, enzyme concentration, substrate molar ratio of methanol to canola oil, and added water content on percentage weight conversion of canola oil methyl ester by alcoholysis. Reaction temperature and enzyme concentration were the most important variables. High temperature and superabundant methanol inhibited the ability of Novozym 435 to catalyze the synthesis of biodiesel. Based on the analysis of ridge max, the optimum synthesis conditions were as follows: reaction time 12.4 h, temperature 38.0 °C, enzyme concentration 42.3%, substrate molar ratio 3.5:1, and added water 7.2%. The predicted value was 99.4% weight conversion, and the actual experimental value was 97.9% weight conversion. Copyright © 2004 Society of Chemical Industry 相似文献
17.
Linqiu Cao Uwe T. Bornscheuer Rolf D. Schmid 《European Journal of Lipid Science and Technology》1996,98(10):332-335
Lipase-catalyzed synthesis of sugar fatty acid esters was performed in a heterogeneous reaction system in the presence of an organic solvent serving as adjuvant. Although the sugar is almost insoluble in such a system, high conversions to the corresponding sugar esters were achieved, due to crystallization of the product. Acylation occurred regioselectively at the primary hydroxyl group and subsequent diacylation was observed only in the case of caprylic acid (2–5%). Best conditions were found for solvents having low log P values and low product solubility such as acetone, using immobilized lipase from Candida antarctica (CAL-B, Novo SP435) and fatty acids with chain lengths from C12 to C8 as acyl donors. The esterification of β-D(+)-glucose with stearic acid resulted in up to 100% conversion after 48 hours equal to a productivity of 0.4 mmol sugar ester per gram lipase and hour. 相似文献
18.
Lipase-catalyzed alcoholysis of soy phospholipids was investigated to simultaneously make lysophospholipids and fatty acid
esters of individual alcohols. Alcoholysis was carried out by stirring a mixture of soy phospholipids and individual alcohols
in equimolar proportions with 10% (by weight of reactants) Mucor miehei lipase at 55°C for 24 h. The products were isolated by column chromatography after removal of the lipase. Lysophospholipids
(in 69–78% molar yield) were obtained from soy phospholipids, and the yield of esters of various alcohols also conformed nearly
with theoretical yields. 相似文献
19.
Melek Tüter H. Aye Aksoy E. Elif Glbaz Emel Kurun 《European Journal of Lipid Science and Technology》2004,106(8):513-517
Esterification of corn and sunflower acid oils with straight‐ and branched‐chain alcohols were conducted using lipase B from Candida antarctica (Novozym 435) in n‐hexane. Sunflower acid oil consisted of 55.6% free fatty acids and 24.7% triacylglycerols, while the free fatty acids and triacylglycerols contents of corn acid oil were 75.3% and 8.6%, respectively. After 1.5 h of methanolysis of sunflower acid oil, the highest fatty acid methyl ester content (63.6%) was obtained at 40 °C and the total fatty acid/methanol molar ratio was 1/1, using 15% enzyme based on acid oil weight. The conversion of both acid oils with straight‐ and branched‐chain alcohols was not significantly affected by the chain length of the alcohols. However, the lowest fatty acid methyl ester content (50%) was obtained in the reaction of corn acid oil with methanol. Sunflower acid oil was converted to fatty acid esters using primer alcohols such as n‐propanol, i‐ and n‐butanol, n‐amylalcohols, n‐octanol, and a mixture of amylalcohol isomers, resulting in a fatty acid ester content of about 70% at 40 °C. 相似文献
20.
Conversion of vegetable oil to biodiesel using immobilized Candida antarctica lipase 总被引:11,自引:8,他引:3
Yuji Shimada Yomi Watanabe Taichi Samukawa Akio Sugihara Hideo Noda Hideki Fukuda Yoshio Tominaga 《Journal of the American Oil Chemists' Society》1999,76(7):789-793
Biodiesel derived from vegetable oils has drawn considerable attention with increasing environmental consciousness. We attempted
continuous methanolysis of vegetable oil by an enzymatic process. Immobilized Candida antarctica lipase was found to be the most effective for the methanolysis among lipases tested. The enzyme was inactivated by shaking
in a mixture containing more than 1.5 molar equivalents of methanol against the oil. To fully convert the oil to its corresponding
methyl esters, at least 3 molar equivalents of methanol are needed. Thus, the reaction was conducted by adding methanol stepwise
to avoid lipase inactivation. The first step of the reaction was conducted at 30°C for 10 h in a mixture of oil/methanol (1:1,
mol/mol) and 4% immobilized lipase with shaking at 130 oscillations/min. After more than 95% methanol was consumed in ester
formation, a second molar equivalent of methanol was added and the reaction continued for 14 h. The third molar equivalent
of methanol was finally added and the reaction continued for 24 h (total reaction time, 48 h). This three-step process converted
98.4% of the oil to its corresponding methyl esters. To investigate the stability of the lipase, the three-step methanolysis
process was repeated by transferring the immobilized lipase to a fresh substrate mixture. As a result, more than 95% of the
ester conversion was maintained even after 50 cycles of the reaction (100 d). 相似文献