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1.
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
2.
Production of n-3 polyunsaturated fatty acid-enriched fish oil by lipase-catalyzed acidolysis without solvent 总被引:1,自引:0,他引:1
Tsuneo Yamane Tomomasa Suzuki Youko Sahashi Line Vikersveen Tamotsu Hoshino 《Journal of the American Oil Chemists' Society》1992,69(11):1104-1107
Fish oil rich in n-3 polyunsaturated fatty acid (n-3 PUFA) was prepared by nonsolvent enzymic acidolysis. n-3 PUFA-enriched
fish oil contained 25% eicosapentaenoic acid (EPA) and 40% docosahexaenoic acid (DHA). In acidolysis of cod liver oil, EPA
content of the original fish oil was reduced at 5 h, but DHA content of the fish oil increased. It was assumed that EPA in
the fish oil was replaced by DHA to reach a new chemical equilibrium. Two-stage acidolysis, which was carried out under CO2 replacement early (about 3 h) and also in vacuum at 5–24 h, was effective for reduction in the content of diacylglycerol,
which was formed by reverse reaction, hydrolysis. This method has industrial significance because PUFA-enriched triacylglycerol
is easily separated from the reaction mixture by molecular distillation.
Bioreactors for fats and their derivatives, Part XIV. 相似文献
3.
Propylene glycol monoesters (PGM) of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are potentially health-beneficial
water-in-oil emulsifiers useful in the food industry. These esters were synthesized enzymatically to overcome the problems
associated with chemical processes. The products were analyzed by gas chromatography. The immobilizedMucor miehei lipase was found to be the best enzyme for the synthesis of both propylene glycol monoesters of EPA and DHA among nine lipases
tested. The anhydrous enzyme and hydrophobic organic solvents were favored for the production of both monoesters. The yields
of monoesters were also affected by temperature, pH memory, fatty acid/propylene glycol ratio, and reaction time. The yields
of PGMDHA and PGMEPA with 50 mM fatty acid and 225 mM propylene glycol as substrates in 1 mL solvent mixture (hexane/t-butyl alcohol=9:1), catalyzed by Lipozyme IM-20 (50 mg) at 40°C for 24 h, were 47 and 49 mM, respectively. The enzyme still
retained over 60% of its original activity after 10 d of batch-type operation (1 d per cycle) at 40°C for the synthesis of
both PGMDHA and PGMEPA. 相似文献
4.
Kojic acid is an inhibitor of bacteria, viruses, and fungi. It is used for inhibiting the browning effect of tyrosinase in
the food and cosmetic industries. To improve its lipophilic properties, Pseudomonas cepacia lipase and Penicillium camembertii lipase were used for catalyzing the esterification of kojic acid to synthesize kojic acid monolaurate and kojic acid monooleate.
These products showed a 69.5% inhibitory effect on tyrosinase in hydrophobic organic solvent. The yields of kojic acid esters
were affected by enzymes, substrates, organic solvent, and temperature. Lauric and oleic acids were the best substrates for
esterification among various fatty acids tested. CaCl2 and MnCl2 stimulate Pseudomonas cepacia lipasecatalyzed esterification by 7.0%. On the contrary, MgCl2, SrCl2, and ZnCl2 inhibited the reaction. The best pH of buffer for lipase pretreatment was pH 6.0. Pseudomonas and Penicillium lipases can be reused for the synthesis of kojic acid esters. After reaction at 40°C for 10 d, the Penicillium and Pseudomonas lipases still retained 57.0% and 92.0% of their initial activities, respectively. 相似文献
5.
Tsuneo Yamane Tomomasa Suzuki Tamotsu Hoshino 《Journal of the American Oil Chemists' Society》1993,70(12):1285-1287
An attempt was made to further increase the content of n-3 polyunsaturated fatty acid (n-3 PUFA) of fish oil by lipase-catalyzed
acidolysis (reaction between fish oil and n-3 PUFA-enriched free fatty acid) without solvent. A bioreactor system was constructed
composed of a water-jacketed packed-bed column and a substrate reservoir with a circulation pipeline between the packed-bed
column and the reservoir. By keeping the temperature of the reservoir at −10°C (for the first 20 h), followed by −20°C (for
the subsequent 40 h) during the batch acidolysis, crystals of free fatty acid appeared, which were removed intermittently
by a cotton plug packed in the tip of the outlet pipe in the reservoir. The n-3 PUFA content of the triacylglycerol fraction
increased a further 10% by the reduced temperature of the reservoir.
Bioreactors for Enzymatic Reaction of Fats and Fatty Acid derivatives, Part XV. 相似文献
6.
Bena‐Marie Lue Salwa Karboune Faustinus K Yeboah Selim Kermasha 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(4):462-468
The esterification of cinnamic acid (CA) and oleyl alcohol (OA) in organic solvent media by immobilized lipase Novozym 435 was optimized in terms of selected parameters, including the logarithm of the 1‐octanol/water partition coefficient of the organic solvent (log P, 0.29–4.5), initial water activity (aw, 0.05–0.75), agitation speed (0–200 rpm), temperature (35–65 °C) and ratio of substrates (CA/OA, 1.0:0.5–1.0:6.0). The results showed that the more hydrophobic solvent mixtures and lower initial aw values resulted in a higher enzymatic activity and bioconversion yield. The most appropriate solvent medium and initial aw value was the mixture of iso‐octane/2‐butanone (85:15, v/v) and 0.05, respectively. The results also showed that an agitation speed of 150 rpm and a reaction temperature of 55 °C were optimal for the reaction system. The activation energy (Ea) of the esterification reaction was calculated as 43.6 kJ mol?1. The optimal ratio of CA to OA was 1.0:6.0, with the absence of any inhibition by OA. Using the optimized conditions, the maximum enzymatic activity was 390.3 nmol g?1 min?1, with a bioconversion yield of 100% after 12 days of reaction. In addition, the electrospray ionization‐mass spectroscopy analysis confirmed that the major end product of the esterification reaction was oleyl cinnamate. Copyright © 2005 Society of Chemical Industry 相似文献
7.
Lipase-assisted concentration of n-3 polyunsaturated fatty acids in acylglycerols from marine oils 总被引:1,自引:0,他引:1
Udaya N. Wanasundara Fereidoon Shahidi 《Journal of the American Oil Chemists' Society》1998,75(8):945-951
Preparation of n-3 polyunsaturated fatty acid (PUFA) concentrates from seal blubber oil (SBO) and menhaden oil (MHO) in the
form of acylglycerols was carried out by hydrolysis with a number of commercial microbial lipases. The lipases tested were
Aspergillus niger, Candida cylindracea (CC), Chromobacterium viscosum, Geotrichum candidum, Mucor miehei, Pseudomonas sp., Rhizopus oryzae, and Rhizopus niveus. After lipase-assisted hydrolysis of oils, free fatty acids were removed, and fatty acid composition of the mixture containing
mono-, di-, and triacylglycerols was determined. All lipases were effective in increasing the n-3 PUFA content of the remaining
acylglycerols of both SBO and MHO. The highest concentration of n-3 PUFA was provided by CC lipase; 43.5% in SBO [9.75% eicosapentaenoic
acid (EPA), 8.61% docosapentaenoic acid (DPA), and 24.0% docosahexaenoic acid (DHA)] and 44.1% in MHO (18.5% EPA, 3.62% DPA,
and 17.3% DHA) after 40 h of hydrolysis. Thus, CC lipase appears to be most suitable for preparation of n-3 PUFA in the acylglycerol
form from marine oils. 相似文献
8.
Yuji Shimada Yoshinori Hirota Takashi Baba Akio Sugihara Shigeru Moriyama Yoshio Tominaga Tadamasa Terai 《Journal of the American Oil Chemists' Society》1999,76(6):713-716
Steryl esters of long-chain fatty acids have water-holding properties, and polyunsaturated fatty acids (PUFA) have various physiological functions. Because steryl ester of PUFA can be expected to have both features, we attempted to synthesize steryl esters of PUFA by enzymatic methods. Among lipases used, Pseudomonas lipase was the most effective for the synthesis of cholesteryl docosahexaenoate. When a mixture of cholesterol/docosahexaenoic acid (3:1, mol/mol), 30% water, and 3000 units/g of lipase was stirred at 40°C for 24 h, the esterification extent attained 89.5%. Under the same reaction conditions, cholesterol, cholestanol, and sitosterol were also esterified efficiently with docosahexaenoic, eicosapentaenoic, arachidonic, and γ-linolenic acids. 相似文献
9.
Fatty acid monoesters of propylene glycol (1,2-propanediol) are good water-in-oil emulsifiers. These esters were synthesized
enzymatically to overcome the problems associated with chemical processes. APseudomonas lipase was added to reaction mixtures containing propylene glycol and various acyl donors (fatty acids, fatty acid ethyl
esters, fatty acid anhydrides and triglycerides) in organic solvents, and the mixtures were shaken at 30°C. The products were
analyzed by gas chromatography. The yield of monoesters was affected by the acyl donors, organic solvents, temperature, water
content, pH memory and reaction time. The anhydrous (lyophilized) enzyme and fatty acid anhydrides were best for monoester
production. The optimum pH ranges were 4–5 and 8–10. The yields of propylene glycol monolaurate, monomyristate, monopalmitate,
monostearate and monooleate with 50 mM fatty acid anhydrides as acyl donors were 97.2, 79.6, 83.7, 89.7 and 93.4 mM, respectively;
those with 50 mM fatty acids as acyl donors were 37.3, 28.7, 28.7, 35.3 and 36.2 mM, respectively. The yields of propylene
glycol monopalmitate, monostearate and monooleate with 50 mM triglycerides as acyl donors were 87.4, 65.1 and 83.2 mM, respectively. 相似文献
10.
Angélica Ganga Susana Nieto Julio Sanhuez Claudio Romo Hernán Speisky Alfonso Valenzuela 《Journal of the American Oil Chemists' Society》1998,75(6):733-736
A simple and relatively inexpensive procedure to obtain 90% eicosapentaenoic acid + docosahexaenoic acid concentrates from
sardine oil involved a two-step winterization of the oil (10 and 4°C), followed by saponification and selective precipitation
of saturated and less unsaturated free fatty acids by an ethanolic solution of urea. Antioxidant effects of butylated hydroxytoluene,
dl-α-tocopherol, and two natural antioxidants, quercetin and boldine, added to the concentrate (0.5% wt/vol), were compared
in the Rancimat at 60°C. dl-α-Tocopherol was unable to inhibit concentrate oxidation. Butylated hydroxyanisole and butylated hydroxytoluene had induction
periods of 1.7–1.8 h compared to the control (1.0 h). A mixture of quercetin + boldine (2:1 w/w) significantly increased the
induction period to 4.5 h. 相似文献
11.
Sugar ester-modified lipase for the esterification of fatty acids and long-chain alcohols 总被引:1,自引:0,他引:1
Sobhi Basheer Mitsutoshi Nakajima Uri Cogan 《Journal of the American Oil Chemists' Society》1996,73(11):1475-1479
The esterification reaction of a long-chain fatty acid and a fatty alcohol with a surfactant-modified lipase in a microaqueousn-hexane system was studied. Various lipases from different sources were first modified with a surfactant of the sugar ester
type to improve their dispersibility in apolar organic solvents. This enzyme modification technique converted inactive crude
lipases to highly active biocatalysts for the esterification of long-chain fatty acids and fatty alcohols in a microaqueous
n-hexane system. The hydrophilic-lipophilic balance value and chainlength of the fatty acid residue of the fatty acid sugar
ester, used for modifying the lipases, significantly influenced the amount of precipitated lipase that was dissolved in the
aqueous solution, the protein content of the lipase-surfactant complex and its esterification activity. 相似文献
12.
Marcel S. F. Lie Ken Jie M. S. K. Syed Rahmatullah 《Journal of the American Oil Chemists' Society》1995,72(11):1381-1384
Enzymatic hydrolysis of synthetic methyl 5-, 9-, and 12-thiastearates in aqueous media withCandida cyclindracea or porcine pancreatic lipases gave the corresponding fatty acids in 70–100% yield. Hydrolysis of the 3- and 4-positional
isomers gave only 15–25% of the free thia fatty acids, suggesting discrimination against these isomers by lipases. No lipolysis
was achieved with methyl 2-thialaurate under a range of reaction conditions. Esterification of the 3-, 4-, 5-, 9-, and 12-thiastearic
acids withn-butanol inn-hexane using Lipozyme (immobilizedRhizomucor miehei) as the biocatalyst gave the corresponding butyl esters in 80–95% yield. Interesterification (acyl exchange) of triolein
with methyl 9-thiastearate in the presence of Lipozyme showed the incorporation of 9-thiastearoyl chain at only one of the
α-positions of triolein. In the case of methyl 2-thialaurate, no lipase-catalyzed acyl exchange reaction was possible. This
study showed that the position of the sulfur atom in thia fatty esters affects the lipase-catalyzed hydrolysis and interesterification
reactions. 相似文献
13.
More than 95% of polyunsaturated acid (PUFA) was converted to triacylglycerol by immobilized lipase fromCandida antarctica orRhizomucor miehei. The esterification was carried out at 50–60°C with shaking and dehydration for 24 h. The substrates consisted of glycerol
and free fatty acid or ethyl esters of the fatty acid at a 1∶3 molar ratio. The docosahexaenoic acid (DHA) or eicosapentaenoic
acid (EPA) in the substrate polymerized during the reaction, and they required 5–10% more than the stoichiometric amount to
compensate for the PUFA loss. On the contrary, ethyl esters of DHA and EPA were not polymerized. Pure tridocosahexaenoyl,
trieicosapentaenoly and triarachidonoyl glycerol were isolated after passing the product through a basic aluminum oxide column.
Industrial feasibility of this process was discussed for the ethyl ester as substrate.
Portions of this article were presented at the annual meeting of the Japan Society for Bioscience, Biotechnology, and Agrochemistry
and at the annual meeting of The Japan Oil Chemists' Society held in Kyoto, Japan, March 31, 1991, and in Hamamatsu, Japan,
October 4, 1991, respectively. 相似文献
14.
Synthesis of polyunsaturated fatty acid-enriched triglycerides by lipase-catalyzed esterification 总被引:2,自引:0,他引:2
L. Esteban Cerdán A. Robles Medina A. Giménez Giménez M. J. Ibáñez González E. Molina Grima 《Journal of the American Oil Chemists' Society》1998,75(10):1329-1337
This paper reports on the synthesis of triglycerides by enzymatic esterification of polyunsaturated fatty acids (PUFA) with
glycerol. A PUFA concentrate obtained from cod liver oil was used to optimize the reaction to favor triglyceride synthesis
with lipases. The type and amount of lipase and organic solvent, glycerol content, temperature, water content, and amount
and time of addition of molecular sieves were studied. The optimal reaction mixture and conditions were: 9 mL hexane, 60°C,
0.5% (vol/vol) water, 1 g molecular sieves added after 24 h of reaction, glycerol/fatty acid molar ratio 1:3 and 100 mg of
Novozym 435 (Novo Nordisk A/S) lipase. Under these conditions, an enriched triglyceride yiedl of 84.7% containing 27.4% eicosapentaenoic
acid and 45.1% docosahexaenoic acid was obtained from a cod liver oil PUFA concentrate. 相似文献
15.
Enrichment of polyunsaturated fatty acids from sardine cannery effluents by enzymatic selective esterification 总被引:1,自引:0,他引:1
Murielle Schmitt-Rozieres Valérie Deyris Louis-Claude Comeau 《Journal of the American Oil Chemists' Society》2000,77(3):329-332
The sardine canning industry produces vast quantities of effluents that need expensive reprocessing. Their oily component
contains valuable n−3 polyunsaturated fatty acids, namely EPA (5,8,11,14,17-eicosapentaenoic acid) and DHA (7,10,13, 16,19-docosahexaenoic
acid), up to 10% each. Our aim was to develop a process allowing the recovery of these fatty acids. After removing solid particles,
proteins, and peptides from the crude effluent, the obtained oil was hydrolyzed. EPA and DHA were enriched from the recovered
free fatty acid fraction by selective enzymatic esterification. Lipases were used as biocatalysts: LipozymeTM allowed up to 80% DHA enrichment but gave no EPA enrichment. By immobilizing Candida rugosa lipase on Amberlite IRC50 cation-exchange resin, a 30% EPA enrichment was obtained. 相似文献
16.
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
17.
Marcel S. F. Lie Ken Jie M. S. K. Syed Rahmatullah 《Journal of the American Oil Chemists' Society》1995,72(2):245-249
Enrichment ofcis-5 polyunsaturated fatty acids [20:3(5c,11c,14c), 4.3% and 20:4(5c,11c,14c,17c), 11.3%] fromBiota orientalis seed oil was carried out by lipase-catalyzed selective esterification and hydrolysis reactions. Lipases fromRhizomucor miehei (Lipozyme),Candida cylindracea and porcine pancreas were used. Lipozyme-catalyzed esterification ofBiota fatty acids withn-butanol inn-hexane allowed 20:3 and 20:4 (as fatty acids) to be enriched to a maximum level of 52.9%, and in the presence ofC. cylindracea lipase 61.5% enrichment was achieved. Esterification with pancreatic lipase was poor with low levels of enrichment of 20:3
and 20:4 (22%). A multigram scale esterification of the free fatty acids fromBiota seed oil by repeated treatment of the isolated fatty acid fraction withn-butanol inn-hexane in the presence ofC. cylindracea lipase furnished an enrichment yield of 72.5% of a mixture of 20:3 and 20:4 fatty acids. Urea fractionation of the free fatty
acids ofBiota oil gave an initial enriched fraction of 20:3 (9.5%) and 20:4 (25.2%) which, upon treatment withC. cylindracea lipase inn-butanol andn-hexane, gave an enriched fraction of 85.3% of 20:3 and 20:4 fatty acids. Partial hydrolysis of the triglycerides ofBiota oil byC. cylindracea lipase in potassium phosphate buffer at 25°C resulted in a 2.8-fold enrichment ofcis-5 polyunsaturated fatty acids (40.8% of 20:3 and 20:4) as contained in the unhydrolyzed acylglycerol fractions. 相似文献
18.
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
19.
Claudia Waldinger Manfred Schneider 《Journal of the American Oil Chemists' Society》1996,73(11):1513-1519
Lipases that display high regioselectivities and broad substrate tolerance were used as catalysts for the efficient esterification
of glycerol under the conditions of irreversible acyl transfer. A variety of unsaturated fatty acids, such as oleic, linoleic,
erucic, ricinolic, hydroxystearic and coriolic acid, were used for this purpose in the form of their vinyl esters. Suitable
biocatalysts were chosen on the basis of systematic screening experiments regarding their regioselectivities (RE) and substrate
tolerances. Distinct differences were found and expressed in numerical RE values as a measure for differences of these biocatalysts
as being specific, selective, and nonspecific. Based on these experiments, a variety of molecules were synthesized on a preparative
scale (>150 mmol) in good yield (ca.85%) and with high regioisomerical purities (>95% RE). 相似文献
20.
Praphan Pinsirodom Kirk L. Parkin 《Journal of the American Oil Chemists' Society》1999,76(10):1119-1125
Fatty acid [FA; butanoic (C4); octanoic (C8); tetradecanoic (C14); and cis-9,12-octadecadienoic (C18:2) acids] reaction selectivity and the corresponding acyl profiles in differentially accumulating acylglycerol (AG) products
(mono-, di-, and triacylglycerols; MAG, DAG, TAG, respectively) were evaluated for Celite™-immobilized potato tuber lipid
acyl hydrolase (LAH)-mediated esterification reactions in isooctane at 35°C and water activity of 0.19. The ordinal pattern
of FA selectivities was C8>C14>C18:2>C4, and the AG products accumulating were α-MAG>DAG>β-MAG>TAG. A dimensionless expression for fatty acid partitioning coefficient
(FAPC) was contrived to represent the partitioning patterns of specific FA into specific AG pools on the basis of an equivalent
extent of FA reaction. These FAPC values indicated that preferential partitioning of FA was as follows: C4 was preferentially partitioned into TAG, DAG, and β-MAG; C8 was preferentially partitioned into DAG; C14 was preferentially partitioned into α,β-MAG; C18:2 was preferentially partitioned into α,β-MAG and TAG. These findings infer that the tendency for LAH-mediated esterifications
to accumulate MAG is based, in part, on a constraint in reactivity of α-MAG of ≥10 acyl carbon groups to serve as acceptors
for further esterification events. The general approach taken in this study may assist in identifying the discrete steps in
assembling structured glycerides where different biocatalysts exhibit the greatest degree or control of reaction selectivity. 相似文献