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1.
P. Scano R. Anedda M. P. Melis M. A. Dessi’ A. Lai T. Roggio 《Journal of the American Oil Chemists' Society》2011,88(9):1305-1316
In this work the molecular fatty components of Pecorino Sardo Protected Designation of Origin (PS PDO) cheese were characterized
through an exhaustive investigation of the 1H- and 13C-NMR spectra of the extracted lipids. Several fatty acids (FA), such as long chain saturated, oleic, linoleic, linolenic,
butyric, capric, caprylic, caproic, trans vaccenic, conjugated linoleic acid (cis9, trans11–18:2), and caproleic (9–10:1) were unambiguously detected. The positional isomery of some acyl groups in the glycerol backbone
of triacylglycerols (TAG) was assessed. Furthermore, the NMR signals belonging to sn-1,2/2,3, sn-1,3 diacylglycerols (DAG), and free fatty acids (FFA) were analysed as a measure of lipolytic processes on cheese. Lastly,
1H-NMR resonances of saturated aldehydes and hydroperoxides were detected, their very low intensity indicating that the lipid
oxidation process can be considered to be of minor relevance in Pecorino Sardo cheese. 相似文献
2.
Stereospecific analysis was carried out to establish positional distribution of FA in the TAG of DHA, EPA, and (EPA+DHA)-enriched
oils. In this study, TAG of enzymatically modified oils were purified using a silicic acid column. The TAG were then subjected
to positional distribution analysis using a modified procedure involving reductive cleavage with Grignard reagent. The results
showed that in DHA-enriched borage oil (BO), DHA was randomly distributed over the three positions of TAG, whereas γ-linolenic
acid (GLA) was mainly esterified at the sn-2 and-3 positions. In DHA-enriched evening primrose oil (EPO), however, DHA and GLA were concentrated in the sn-2 position. In EPA-enriched BO, EPA was randomly distributed over the three positions of TAG, similar to that observed for
DHA. In EPA-enriched EPO, however, this FA was mainly located at the primary positions (sn-1 and sn-3) of TAG. In both oils, GLA was preferentially esterified at the sn-2 position. In (EPA+DHA)-enriched BO, EPA and DHA were mainly esterified at the sn-1 and -3 positions of TAG, whereas GLA was mainly located at the sn-2 position. In (EPA+DHA)-enriched EPO, GLA was mainly located at the sn-2 and-3 positions; EPA was preferentially esterified at the sn-1 and-3 positions, and DHA was found mainly at the sn-3 position. 相似文献
3.
The lipase-assisted acidolysis of high-laurate canola oil (HLCO; Laurical 25) with long-chain n−3 FA (DHA and EPA) was studied.
Response surface methodology was used to obtain a maximal incorporation of DHA or EPA into HLCO. The studied process variables
were the amount of enzyme (2–6%), reaction temperature (35–55°C), and incubation time (12–36 h). The amount of water added
and the mole ratio of substrates (oil to DHA or EPA) were kept at 2% and 1∶3, respectively. All experiments were conducted
according to a face-centered cube design. Under optimal conditions (4.79% of enzyme; 46.1°C; 30.1 h), the incorporation of
DHA into HLCO was 37.3%. The corresponding maximal incorporation of EPA (61.6%) into Laurical 25 was obtained using 4.6% enzyme,
a reaction temperature of 39.9°C, and a reaction period of 26.2 h. Examination of the positional distribution of FA on the
glycerol backbone of modified HLCO with DHA showed that the DHA was primarily located in the sn-1,3 positions of the TAG molecules. However, lauric acid also remained mainly in the sn-1,3 positions of the modified oil. For EPA-modified Laurical 25, lauric acid was present mainly in the sn-1,3 positions, whereas EPA was randomly distributed over the three positions. 相似文献
4.
The production of structured lipids via acidolysis of high-laurate canola oil (Laurical 15) with EPA in hexane was carried
out using lipase from Pseudomonas sp. The optimal reaction conditions used 4% lipase, at a mole ratio of oil to EPA of 1∶3 at 45°C over 36 h. The positional distribution
of FA on the glycerol backbone of unmodified oil indicated that lauric acid was mainly located at the sn-1,3 positions. Stereospecific analysis of the oil modified with EPA showed that lauric acid remained mostly esterified to
the sn-1,3 positions of the TAG molecules and that EPA was also primarily in the sn-1,3 positions of the TAG molecules. Thus, the resultant structured lipids may have optimal value for use in applications
where quick energy release and EPA supplementation are required. 相似文献
5.
Matthew R. Miller Nigel B. Perry Elaine J. Burgess Susan N. Marshall 《Journal of the American Oil Chemists' Society》2011,88(4):509-516
The lipid profiles of the two most important New Zealand marine oil sources were investigated, with particular attention to
the regioisomeric compositions of triacylglycerides (TAG), using 13C-nuclear magnetic resonance analysis. Oils from hoki (Macruronus novaezelandiae) and Greenshell™ mussel (Perna canaliculus) (GSM) were analyzed for their lipid content, lipid class and fatty acid profile. The regiospecific distribution of long
chain (C ≥ 20) polyunsaturated fatty acids (LC-PUFA) between the sn-1,3 and sn-2 glycerol positions was calculated from 13C responses in the carbonyl region in the triacylglycerol fraction. Rendered hoki oil (RHO) produced from the viscera and
filleting discards, had a similar lipid profile to that of hoki liver oil (HLO) confirming that the liver is the major source
of oil in RHO. The regioisomeric distribution of fatty acids showed differences between the two oil sources. Docosahexaenoic
acid (DHA) had a regioisomeric distributional preference to the sn-2 position in TAG from all the oils (59.2% HLO, 54.3% RHO and 63.4% GSM). Eicosapentaenoic acid (EPA) had a more even distribution
along the triacylglycerol backbone in hoki TAG (29.1% HLO, 33.6% RHO) while there was a slight sn-2 positional preference in the GSM TAG (37.6%). This regioisomeric information is vital to distinguish LC-PUFA-rich marine
oils from other marine sources for authentication purposes. 相似文献
6.
A very simple and versatile GC method has been developed that can be utilized for quick analysis, in many samples, of the
FA compositions at the sn-2- and sn-1,3-positions of TAG. By using the lipase-catalyzed, sn-1,3-regioselective esterexchange reaction of TAG with ethyl acetate, followed by direct injection of the crude reaction mixture
into the GC apparatus without any pretreatment, the FA located at the sn-2-position could accurately be analyzed as a TAG derivative in which the sn-1,3-positions were substituted by an acetate residue. Furthermore, the FA located at the sn-1,3-positions could simultaneously be analyzed as the corresponding ethyl ester derivatives using this method. The reliability
of the analytical method was compared with conventional methods by analyzing the TAG consisting of caprylic acid (C) at the
sn-2-position and oleic acid (O) at the sn-1,3-positions, giving comparable analytical results. The present method was applied to the analysis of the structured lipids
CCD and CCE, consisting of TAG as a major component in which C and the highly unsaturated FA, DHA (D) or EPA (E), were specifically
bound at the sn-2- and the sn-1,3-positions, respectively. 相似文献
7.
Synthesis and Structural Analysis of Structured Triacylglycerols with CLA Isomers in the <Emphasis Type="Italic">sn</Emphasis>-2- Position 总被引:1,自引:1,他引:0
Francesca Blasi Lina Cossignani Ancilla Bosi Silvia Maurelli Gilda D’Arco Dennis Fiorini Maria Stella Simonetti Pietro Damiani 《Journal of the American Oil Chemists' Society》2008,85(7):613-619
The present research deals with the chemical esterification of the sn-2- position of sn-1,3-diacylglycerol (sn-1,3-DAG) with 9cis,11trans (c9,t11) and 10trans,12cis (t10,c12) conjugated linoleic acid (CLA) isomers to obtain structured triacylglycerols (TAG); the sn-1,3-DAG substrates were produced from extra virgin olive oil by means of enzymatic reactions while CLA isomers were obtained
using a three-step procedure based on alkaline hydrolysis of sunflower oil, urea purification of linoleic acid (LA) and alkaline
isomerization of LA. The results showed good levels of CLA incorporation in structured TAG at the tested temperatures: 37.5%
at 4 °C and 39.1% at 14 °C. To evaluate the incorporation of CLA isomers in sn-2- position of sn-1,3-DAG structural analysis of the newly synthesized TAG was carried out using an enzymatic and a chemical method. The results
of the structural analysis also showed up the occurrence of acyl migration. The pancreatic lipase method allowed the direct
determination of the fatty acid composition of TAG sn-2- position but this enzymatic method showed different results (p < 0.05) in respect to the chemical one; this occurrence could be due to an acylic specificity of the lipase. High incorporation
of CLA isomers in sn-2- position of TAG was observed, 77.0% at 4 °C and 81.5% at 14 °C, considering the results of the chemical procedure. 相似文献
8.
Silvia Maurelli Francesca Blasi Lina Cossignani Ancilla Bosi Maria Stella Simonetti Pietro Damiani 《Journal of the American Oil Chemists' Society》2009,86(2):127-133
The synthesis of structured triacylglycerols (TAG) by the enzymatic reaction between sn-1,3-diacylglycerols (sn-1,3-DAG) and conjugated linoleic acid (CLA) isomers was studied. Both the substrates of the reaction were produced from vegetable
oils, the sn-1,3-DAG from extra virgin olive oil and the CLA isomers from sunflower oil. The enzymatic reactions between these substrates
were catalyzed for 96 h by an immobilized lipase from Rhizomucor miehei (Lipozyme IM) and the reactions carried out in solvent were monitored every 24 h by using high-performance liquid chromatography-evaporative
light scattering detector (HPLC-ELSD). The enzymatic reactions were carried out in different reaction media (hexane, isooctane
and solvent free) and with different CLA/sn-1,3-DAG ratios. Total % acidic composition and structural analysis data were evaluated to verify the presence of CLA isomers
in sn-2- position of synthesized TAG. The results showed good levels of CLA incorporation in sn-1,3-DAG, from 19.2% of TAG synthesized in solvent free conditions with a 0.5:1 substrate ratio, to 47.5% of TAG synthesized
in isooctane with a 2:1 substrate ratio. It was observed that for all the reaction media, the best sn-2- acylic specificity was obtained with a 0.5:1 substrate ratio. 相似文献
9.
Yomi Watanabe Shinichi Sato Saiko Sera Chiemi Sato Kazuaki Yoshinaga Toshiharu Nagai Ryota Sato Hiroaki Iwasaka Tsunehiro Aki 《Journal of the American Oil Chemists' Society》2014,91(8):1323-1330
A protocol for the analysis of the positional distribution of fatty acids (FA) in solid triacylglycerols (TAG) was developed using sn-1(3) selective alcoholysis catalyzed by immobilized Candida antarctica lipase B (CALB). One part by weight of solid fat and ten parts by weight of ethanol (99.5 %) were warmed to liquefy the fat. After adding 0.44 parts by weight of CALB, the mixture was shaken at 50 °C for 10 min then at 30 °C for 2.8 h. The recovery of 2-MAG after the 3-h transesterification reaction was ca. 85 % of the maximum theoretical yield (33 mol%), with the loss of 15 % attributable to the acyl migration from sn-2 to sn-1(3). The recovery was similar to that of the solvent-free alcoholysis of structured lipids, 1,3-dipalmitoyl, 2-oleoyl glycerol and 1,3-dioleoyl, 2-palmitoyl glycerol, conducted at 30 °C for 3 h. In contrast, the acyl migration from sn-1(3) to sn-2 was hardly observed. Because the detected acyl migration was only in the direction of sn-2 to sn-1(3), and not vice versa, it is proposed to determine the FA composition of the sn-2 position of TAG by the gas chromatographic analysis of 2-MAG fraction recovered from the enzymatic reaction mixture, and the FA composition of sn-1(3) position by a mass balance using the FA composition of TAG and of the sn-2 position as inputs. The procedure was successfully applied to palm oil and shea butter, and docosahexaenoic acid (DHA)-rich single cell oil from Aurantiochytrium sp. KH105 for the first time. 相似文献
10.
PA Gonzlez Moreno A Robles Medina F Camacho Rubio B Camacho Pez L Esteban Cerdn E Molina Grima 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(1):35-43
Structured triacylglycerols with caprylic acid at the sn‐1 and sn‐3 positions of the glycerol backbone and eicosapentaenoic acid (EPA) at the position sn‐2 were synthesised by acidolysis of a commercially available EPA‐rich oil (EPAX4510, Pronova Biocare) and caprylic acid catalysed by the 1,3‐specific immobilised lipase Lipozyme IM. The reaction was carried out in an immobilised lipase packed‐bed reactor by recirculating the reaction mixture through the bed. The exchange equilibrium constants between caprylic acid and the native fatty acids of EPAX4510 were determined. The n‐3 polyunsaturated fatty acids (PUFAs), EPA and docosohexaenoic acid (DHA), were the most easily displaced by the caprylic acid. The exchange equilibrium constants were 3.68 and 3.06 for EPA and DHA, respectively. The influence of the flow rate of the reaction mixture through the packed‐bed and the substrate concentration in the reaction rate were studied. For flow rates between 74 and 196 cm3 h?1 (bed of 6.6 mm internal diameter and 0.46 porosity) and triacylglycerol concentrations between 0.036 and 0.108 M , the data fitted well to an empirical kinetic model which allowed representative values of the apparent kinetic constant to be obtained. Hence, the average reaction rates and kinetic constants of exchange of caprylic acid and native fatty acids of EPAX4510 could be calculated. In the conditions indicated, the parameter (lipase mass × time/triacylglycerol mass, mLt/V[TG]0) constituted the intensive variable of the process for use in predicting the composition of structured triacylglycerols at different reaction times. At equilibrium, the structured triacylglycerol produced had the following composition: caprylic acid 59.5%, EPA 9.6%, DHA 2.2% and oleic acid 11.8%. Copyright © 2004 Society of Chemical Industry 相似文献
11.
Maria das Graças Coelho de Souza Cristiane Maria Simonato Conde Camila Maurente Laflôr Fernando Lencastre Sicuro Eliete Bouskela 《Lipids》2015,50(1):23-37
Ischemia/reperfusion (I/R) injury can occur in consequence of myocardial infarction, stroke and multiple organ failure, the most prevalent cause of death in critically ill patients. I/R injury encompass impairment of endothelial dependent relaxation, increase in macromolecular permeability and leukocyte‐endothelium interactions. Polyunsaturated fatty acids (n‐3 PUFA), such as eicosapentaenoic acid (EPA, 20:5n‐3) and docosahexaenoic acid (DHA, 22:6n‐3) found in fish oil have several anti‐inflammatory properties and their potential benefits against I/R injury were investigated using the hamster cheek pouch preparation before and after ischemia. Before the experiments, hamsters were treated orally with saline, olive oil, fish oil and triacylglycerol (TAG) and ethyl ester (EE) forms of EPA and DHA at different daily doses for 14 days. Fish oil restored the arteriolar diameter to pre ischemic values during reperfusion. At onset and during reperfusion, Fish oil and DHA TAG significantly reduced the number of rolling leukocytes compared to saline and olive oil treatments. Fish oil, EPA TAG and DHA TAG significantly prevented the rise on leukocyte adhesion compared to saline. Fish oil (44.83 ± 3.02 leaks/cm2), EPA TAG (31.67 ± 2.65 leaks/cm2), DHA TAG (41.14 ± 3.63 leaks/cm2), and EPA EE (30.63 ± 2.25 leaks/cm2), but not DHA EE (73.17 ± 2.82 leaks/cm2) prevented the increase in macromolecular permeability compared to saline and olive oil (134.80 ± 1.49 and 121.00 ± 4.93 leaks/cm2, respectively). On the basis of our findings, we may conclude that consumption of n‐3 polyunsaturated fatty acids, especially in the triacylglycerol form, could be a promising therapy to prevent microvascular damage induced by ischemia/reperfusion and its consequent clinical sequelae. 相似文献
12.
Isabel Medina Raffaele Sacchi Santiago Aubourg 《Journal of the American Oil Chemists' Society》1994,71(5):479-482
13C Nuclear magnetic resonance spectroscopy was applied to the study of lipid hydrolysis occurring during industrial canning
of tuna (Thunnus alalunga). An increase in the free fatty acid (FFA) level was observed after cooking and sterilization, and a different FFA pattern
was found when storage of the frozen raw material and thermal steps (cooking and can sterilization) were compared. Lipolysis
in raw muscle occurs preferentially in thesn-1 andsn-3 acyl positions of triacylglycerols, with a consequent cleavage of saturated and monounsaturated fatty acids. After thermal
processing, an increase of docosahexaenoic acid (DHA) was found in the FFA fraction, as well as a relative decrease of the
peak intensity of DHA in thesn-2 position of triacylglycerols. This finding indicates a different mechanism of FFA release during the frozen storage and
thermal processing of raw fish. 相似文献
13.
Betty Mbatia Bo Mattiasson Francis Mulaa Patrick Adlercreutz 《European Journal of Lipid Science and Technology》2011,113(6):717-723
PUFA from oil extracted from Nile perch viscera were enriched by selective enzymatic esterification of the free fatty acids (FFA) or by hydrolysis of ethyl esters of the fatty acids from the oil (FA‐EE). Quantitative analysis was performed using RP‐HPLC coupled to an evaporative light scattering detector (RP‐HPLC‐ELSD). The lipase from Thermomyces lanuginosus discriminated against docosahexaenoic acid (DHA) most, resulting in the highest DHA/DHA‐EE enrichment while lipase from Pseudomonas cepacia discriminated against eicosapentaenoic acid (EPA) most, resulting in the highest EPA/EPA‐EE enrichment. The lipases discriminated between DHA and EPA with a higher selectivity when present as ethyl esters (EE) than when in FFA form. Thus when DHA/EPA were enriched to the same level during esterification and hydrolysis reactions, the DHA‐EE/EPA‐EE recoveries were higher than those of DHA/EPA‐FFA. In reactions catalysed by lipase from T. lanuginosus, at 26 mol% DHA/DHA‐EE, DHA recovery was 76% while that of DHA‐EE was 84%. In reactions catalysed by lipase from P. cepacia, at 11 mol% EPA/EPA‐EE, EPA recovery was 79% while that of EPA‐EE was 92%. Both esterification of FFA and hydrolysis of FA‐EE were more effective for enriching PUFA compared to hydrolysis of the natural oil and are thus attractive process alternatives for the production of products highly enriched in DHA and/or EPA. When there is only one fatty acid residue in each substrate molecule, the full fatty acid selectivity of the lipase can be expressed, which is not the case with triglycerides as substrates. 相似文献
14.
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
15.
This paper presents the positional distribution of fatty acids in triacyl-sn-glycerols (TAG) of Artemia nauplii used in aquaculture as a live food for marine fish larvae. The nauplii were enriched with docosahexaenoic acid (DHA)
ethyl ester (EE) in the form of gelatin-acacia microcapsules for 4, 18, and 24 h. TAG of the initial, enriched, and unenriched
Artemia nauplii were subjected to stereospecific analysis. A remarkable increase of DHA content in the enriched Artemia TAG confirmed the view that DHA-EE is effectively assimilated and incorporated into the TAG fraction of Artemia nauplii. TAG of the nauplii enriched with 25 mg/L of DHA-EE contained DHA at concentrations of 5.9–6.8, 4.3–6.0, and 14.3–22.3
mol% in the sn-1, sn-2, and sn-3 positions, respectively. When the nauplii were enriched with 100 mg/L of DHA-EE, proportions of DHA in the sn-1, sn-2, and sn-3 positions were 5.2–8.6, 3.9–6.0, and 12.2–25.4 mol%, respectively. In all of the enriched Artemia, DHA was preferentially located in the sn-3 position followed in sequence by the sn-1 and sn-2 positions. The lower content of DHA in the sn-1 and sn-2 positions was consistent with low content of this acid in 1,2-diacyl-sn-glycerophospholipids. When fish larvae are reared on Artemia nauplii enriched with LL-type DHA oil, the larvae feed on DHA esterified in TAG with a positional distribution pattern similar
to that of marine mammals (sn-3≫sn-1>sn-2) rather than that of fish or marine invertebrates (sn-2≫sn-3>sn-1). 相似文献
16.
Carlos F. Torres Hugo S. Garcia Jason J. Ries Charles G. Hill Jr. 《Journal of the American Oil Chemists' Society》2001,78(11):1093-1098
Free fatty acids from fish oil were prepared by saponification of menhaden oil. The resulting mixture of fatty acids contained
ca. 15% eicosapentaenoic acid (EPA) and 10% docosahexaenoic acid (DHA), together with other saturated and monounsaturated fatty
acids. Four commercial lipases (PS from Pseudomonas cepacia, G from Penicillium camemberti, L2 from Candida antarctica fraction B, and L9 from Mucor miehei) were tested for their ability to catalyze the esterification of glycerol with a mixture of free fatty acids derived from
saponified menhaden oil, to which 20% (w/w) conjugated linoleic acid had been added. The mixtures were incubated at 40°C for
48h. The ultimate extent of the esterification reaction (60%) was similar for three of the four lipases studied. Lipase PS
produced triacylglycerols at the fastest rate. Lipase G differed from the other three lipases in terms of effecting a much
slower reaction rate. In addition, the rate of incorporation of omega-3 fatty acids when mediated by lipase G was slower than
the rates of incorporation of other fatty acids present in the reaction mixture. With respect to fatty acid specificities,
lipases PS and L9 showed appreciable discrimination against esterification of EPA and DHA, respectively, while lipase L2 exhibited
similar activity for all fatty acids present in the reaction mixture. The positional distribution of the various fatty acids
between the sn-1,3 and sn-2 positions on the glycerol backbone was also determined. 相似文献
17.
Preparation of Infant Formula Fat Analog Containing Capric Acid and Enriched with DHA and ARA at the sn-2 Position
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An infant formula fat analog with capric acid mostly esterified at the sn‐1,3 positions, and substantial amounts of palmitic, docosahexaenoic (DHA), and arachidonic (ARA) acids at the sn‐2 position, was prepared by physically blending enzymatically synthesized structured lipids (SL) with vegetable oils. The components of the blend included high sn‐2 palmitic acid SL enriched with capric acid (SLCA), canola oil (CAO), corn oil (CO), high sn‐2 DHA (DHAOm), and high sn‐2 ARA (ARAOm) enzymatically modified oils. Each component was proportionally blended to match the fatty acid profile of commercial fat blends used for infant formula. The infant formula fat analog (IFFA1) was characterized for total and positional fatty acids (FA), triacylglycerol (TAG) molecular species, thermal behavior, and tocopherol content. IFFA1 contained 17.37 mol% total palmitic acid of which nearly 35 % was located at the sn‐2 position. The total capric acid content was 13.93 mol%. The content of DHA and ARA were 0.49 mol% (48.18 % at sn‐2) and 0.57 mol% (35.80 % at sn‐2), respectively. The predominant TAG were OPO (24.09 %), POP (15.70 %), OOO (11.53 %), and CLC (7.79 %). The melting completion and crystallization onset temperatures were 18.65 and ?2.19 °C, respectively. The total tocopherol content was 566.45 μg/g. This product might be suitable for commercial production of infant formulas. 相似文献
18.
Tengku Mohamad Tengku-Rozaina Edward John Birch 《Journal of the American Oil Chemists' Society》2013,90(8):1111-1119
Enrichment of the omega-3 (n-3) fatty acids of refined hoki oil (RHO) intact triglycerides (TG) and via free fatty acids (FFA), was carried out in the present study using established methods of dry fractionation (DF), low temperature solvent crystallization (LTSC) and urea complexation (UC) and positional distribution of fatty acids in the intact TG was determined by Nuclear Magnetic Resonance (NMR) analysis. Results showed that n-3 fatty acids were enriched in liquid fractions of all methods except DF, where the highest concentration was obtained via the UC method (83.00 %). The FFA form of the oil produced a higher concentration (40.81 %) of n-3 fatty acids via the LTSC method compared to the TG form (31.50 %). The percentages of the total saturated fatty acid (SFA) in the liquid fractions in all methods were lower, ranging from 1.60 % (UC) to 21.44 % (DF) compared to the RHO parent oil (24.05 %). The percentages of total monounsaturated fatty acids (MUFA) in the liquid fractions were similar to the solid fractions except for the UC method where total MUFA was six times higher in the solid fraction. In LTSC-FFA and UC methods, the enrichment factor for EPA was lower, ranging from 1.61 (LTSC-FFA) to 2.83 (UC), than DHA which ranged from 1.64 (LTSC-FFA) to 3.88 (UC). EPA was preferentially located at the sn-1,3 position and DHA was significantly located at the sn-2 position which is the favoured location for intestinal digestion. 相似文献
19.
Gloria Fernández-Lorente Carolina Pizarro Dolores López-Vela Lorena Betancor Alfonso V. Carrascosa Benevides Pessela Jose M. Guisan 《Journal of the American Oil Chemists' Society》2011,88(6):819-826
A new assay was designed to measure the release of omega-3 acids [eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)]
from the hydrolysis of sardine oil by lipases immobilized inside porous supports. A biphasic system was used containing the
fish oil dissolved in the organic phase and the immobilized lipase suspended in the aqueous phase. The assay was optimized
by using a very active derivative of Rhizomucor miehei lipase (RML) adsorbed onto octyl-Sepharose. Standard reaction conditions were: (a) an organic phase composed by 30/70 (v:v)
of oil in cyclohexane, (b) an aqueous phase containing 50 mM methyl-cyclodextrin in 10 mM Tris buffer at pH 7.0. The whole
reaction system was incubated at 25 °C. Under these conditions, up to 2% of the oil is partitioned into the aqueous phase
and most of the 95% of released acids were partitioned into the organic phase. The organic phase was analyzed by RP-HPLC (UV
detection at 215 nm) and even very low concentrations (e.g., 0.05 mM) of released omega-3 fatty acid could be detected with
a precision higher than 99%. Three different lipases adsorbed on octyl-Sepharose were compared: Candida antarctica lipase-fraction B (CALB), Thermomyces lanuginosa lipase (TLL) and RML. The three enzyme derivatives were very active. However, most active and selective towards polyunsaturated
fatty acids (PUFA) versus oleic plus palmitic acids (a fourfold factor) was CALB. On the other hand, the most selective derivatives
towards EPA versus DHA (a 4.5-fold factor) were TLL and RML derivatives. 相似文献
20.
Docosahexaenoic Acid is More Stable to Oxidation when Located at the sn-2 Position of Triacylglycerol Compared to sn-1(3) 总被引:1,自引:0,他引:1
Chakra Wijesundera Claudio Ceccato Peter Watkins Peter Fagan Benjamin Fraser Neeranat Thienthong Patrick Perlmutter 《Journal of the American Oil Chemists' Society》2008,85(6):543-548
Regio-isomeric effects on the oxidative stability of triacylglycerols (TAG) containing docosahexaenoic acid (DHA) were investigated
using two pairs of regio-isomerically pure TAG, namely 1,3-dihexadecanoyl-2-(4,7,10,13,16,19-docosahexaenoyl)glycerol (PDP)/1,2-dihexadecanoyl-3-(4,7,10,13,16,19-docosahexaenoyl)glycerol
(PPD) and 1,3-dioctadecenoyl-2-(4,7,10,13,16,19-docosahexaenoyl)glycerol (ODO)/1,2-dioctadecenoyl-3-(4,7,10,13,16,19-docosahexaenoyl)glycerol
(OOD) where P, O, and D represent palmitic acid, oleic acid, and DHA respectively. Each pair of regio-isomers was subjected
to accelerated auto-oxidation (at 40 or 50 °C inside a dark oven). In each case, the TAG oxidized more slowly when DHA was
located at the sn-2 position (PDP and ODO) compared to the sn-1(3) position (PPD and OOD), as evidenced by slower development of peroxide value, slower depletion of DHA, and slower generation
of secondary oxidation products propanal and trans, trans-2,4-heptadienal. The positional effect on auto-oxidation was more pronounced when DHA occurred in combination with oleic
acid than with palmitic acid. 相似文献