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1.
Masamichi Akimoto 《Applied biochemistry and biotechnology》1998,74(1):31-41
In order to decrease the content of linoleoyl moiety in soybean oil, soybean oil that contains 22.8% oleoyl, 54.8% linoleoyl, and 7.1% α-linolenoyl moieties as molar acyl moiety composition was interesterified in hexane with oleic acid or α-linolenic acid, using an immobilized sn-l,3-specific lipase (Lipozyme® IM) fromMucor miehei. The reactions were carried out in a batch reactor at 37°C in the following system: molar ratio of fatty acid to soybean oil = 1.0 ~ 6.0, 5.0 mL of hexane/500 μmol soybean oil, and 10.0 or 15.0 batch interesterification units of enzyme/500 μmol soybean oil. Under these reaction conditions, the rates of interesterification of acyl moieties in soybean oil were of the order: stearoyl > palmitoyl > linoleoyl > oleoyl > α-linolenoyl, and the reaction with oleic acid occurred without a significant loss of α-linolenoyl moiety. At the molar ratio of 3.0 and the reaction time of 6 h, triacylglycerols (TGs), which contain 50.8% oleoyl, 38.8% linoleoyl, and 5.4% α-linolenoyl moieties, were produced in the reaction with oleic acid; TGs that contain 13.5% oleoyl, 40.8% linoleoyl, and 40.4% α-linolenoyl moieties were obtained with α-linolenic acid. Approximately 86-88% of the interesterification of linoleoyl moiety, which occurred in 10 h, took place within 1 h. 相似文献
2.
To provide a mathematical basis for the design and operation of a continuous, packed-bed reactor for the interesterification
of soybean oil, soybean oil that contains 22.7% oleoyl and 54.3% linoleoyl moieties as molar acyl moiety composition was interesterified
in hexane with oleic acid, using an immobilized sn-1,3-specific lipase (Lipozyme IM) from Mucor miehei. The reaction was carried out in a U-shaped Pyrex glass-made packed-bed reactor at 37°C in the following system: concentration
of soybean oil in the feed stream=12.5 wt%, molar ratio of fatty acid to soybean oil=3.0, and water content in the feed stream=1340–2340
ppm. At these water contents, Lipozyme IM gave practically the same catalytic activity, and the content of triacylglycerols
in the product oil was 91–94 wt%. Rate equations for the change in oleoyl and linoleoyl moiety compositions in soybean oil
were derived and their validity was confirmed experimentally. On the other hand, the catalytic activity of Lipozyme IM decayed
in the first-order fashion. Based on these deactivation kinetics, the flow rate of the feed stream is simulated for the operation
of a continuous, packed-bed reactor at 37°C that produces an oil of a fixed composition of oleoyl moiety. 相似文献
3.
Marija Takic Biljana Pokimica Gordana Petrovic-Oggiano Tamara Popovic 《Molecules (Basel, Switzerland)》2022,27(14)
The essential fatty acid alpha-linolenic acid (ALA) is present in high amounts in oils such as flaxseed, soy, hemp, rapeseed, chia, and perilla, while stearidonic acid is abundant in echium oil. ALA is metabolized to eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) by desaturases and elongases in humans. The conversion of ALA to EPA and DHA is limited, and these long-chain n−3 polyunsaturated fatty acids (PUFAs) are mainly provided from dietary sources (fish and seafood). This review provides an overview of studies that explored the effects of dietary supplementation with ALA in obesity and related diseases. The obesity-associated changes of desaturase and elongase activities are summarized, as they could influence the metabolic conversion of ALA. Generally, supplementation with ALA or ALA-rich oils leads to an increase in EPA levels and has no effect on DHA or omega-3 index. According to the literature data, stearidonic acid could enhance conversion of ALA to long-chain n−3 PUFA in obesity. Recent studies confirm that EPA and DHA intake should be considered as a primary dietary treatment strategy for improving the omega-3 index in obesity and related diseases. 相似文献
4.
Human Milk is naturally the only source of food for infant in their early life. It contains 2-6% lipid which provides about 50% of the total energy needed by the infant. Human milk fat (HMF) mainly as TAG with the specific fatty acid composition, palmitic acid (C16:0) (20-25%), which is primary located at sn-2 of glycerol bonds (70%) and oleic acid (C18:1), located at sn-1,3 (35%). HMF also provide fatty acids such as linoleic acid, linolenic acid, EPA, DHA and lauric acid that are very important for infant. The purposes of this research are to synthesize of 1,3-dioleoyl-2-palmitoilglycerol (OPO) and to determine the best composition of OPO, VCO, soybean oil and fish oil for HMFS production for infant formula. Interesterification of tripalmitin and ethyl oleate using immobilized lipase from Rhizomucor miehei (Lipozym RM IM) were used to synthesize of OPO. Interesterification product of mixed VCO, soybean oil and fish oil that are source of lauric acid, linoleic acid, α-linolenic, EPA and DHA, were formulated in mass ratio (58:20:20:2) and (70:18:10:2) for obtaining HMFS which have fatty acids composition similar or close to HMF. Composition of fatty acids from product were analyzed by GCMS. From this research, were obtained HMFS containing palmitic acid as much as 28.89% where 84.49% of that are located at sn-2 while sn-1,3 position are dominated by oleic acid as much as 55.11% from the total 38.7% and 70:18:10:2 w/w is the best composition of interesterification product, VCO, soybean oil and fish oil to obtain HMFS similar to HMF. 相似文献
5.
5种贝类脂肪含量及脂肪酸组成研究 总被引:8,自引:0,他引:8
用氯仿 甲醇法测定了广州海鲜市场上棕带仙女蛤、波纹巴非蛤、文蛤、栉孔扇贝和园华扇贝等 5种贝类的脂肪含量 ,并用GC MS法测定了它们的脂肪酸组成。 5种贝类鉴定出的脂肪酸都在 99% (质量分数 )以上。它们的脂肪含量都大于 1% (质量分数 ) ,园华扇贝的脂肪含量最高。它们的ω 3多不饱和脂肪酸与ω 6多不饱和脂肪酸含量的比值基本上都大于 2。两种扇贝的廿碳五烯酸 (EPA)和廿二碳六烯酸 (DHA)含量都比较高。分析结果表明 ,园华扇贝不仅脂肪含量高 ,而且EPA与DHA的含量也比较高 ,是EPA和DHA理想的提取原料 相似文献
6.
Davis TA Gao L Yin H Morrow JD Porter NA 《Journal of the American Chemical Society》2006,128(46):14897-14904
The effect of lipid composition on the distribution of free radical oxidation products derived from arachidonic acid (20:4) esters has been studied in vitro and in vivo. Pro-inflammatory prostaglandin (PG) F2-like compounds, termed F2-isoprostanes (IsoPs), are produced in vivo and in vitro by the free radical-catalyzed peroxidation of arachidonic acid. Controlled free radical oxidation of mixtures of fatty acid esters in vitro showed that the formation of IsoPs from arachidonate is dramatically influenced by the presence of other fatty acid esters in the reaction mixture. Thus, three lipid mixtures containing the same arachidonate concentration but different amounts of other fatty esters (16:0; 18:1; 18:2; 20:5, and 22:6) were oxidized, and the product yields were determined by GC and LC/MS/MS analysis. The yield of F2-IsoP formed after 1 h of oxidation was 18% (based on arachidonate consumed) for mixtures containing arachidonate as the only oxidizable PUFA, but yields of these biologically active compounds dropped to 6% in polyunsaturated fatty acid (PUFA) mixtures typical of those found in tissues of fish oil-fed animals. F2-IsoP levels were also monitored in the livers of mice on diets supplemented with eicosapentaenoic acid (C20:5 omega-3; EPA), the PUFA most abundant in fish oil. While the level of arachidonic acid present in livers was not significantly different from that in control animals, levels of IsoPs in the liver were reduced in the EPA-fed mice compared to those in controls under conditions of oxidative stress (60 +/- 25% reduction, n = 5) or at baseline (48 +/- 14% reduction, n = 5). These results suggest that dietary omega-3 PUFAs may influence the formation of bio-active peroxidation products derived from omega-6 PUFAs by channeling the free radical pathway away from the F2-IsoPs. 相似文献
7.
Shohei Hayashi Mai Naka Kenshin Ikeuchi Makoto Ohtsuka Kota Kobayashi Yasuharu Satoh Yasushi Ogasawara Chitose Maruyama Yoshimitsu Hamano Tetsuro Ujihara Tohru Dairi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(20):6677-6682
Polyunsaturated fatty acids (PUFAs) such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are essential fatty acids. PUFA synthases are composed of three to four subunits and each create a specific PUFA without undesirable byproducts. However, detailed biosynthetic mechanisms for controlling final product profiles have been obscure. Here, the bacterial DHA and EPA synthases were carefully dissected by in vivo and in vitro experiments. In vitro analysis with two KS domains (KSA and KSC) and acyl‐acyl carrier protein (ACP) substrates showed that KSA accepted short‐ to medium‐chain substrates while KSC accepted medium‐ to long‐chain substrates. Unexpectedly, condensation from C18 to C20, the last elongation step in EPA biosynthesis, was catalyzed by KSA domains in both EPA and DHA synthases. Conversely, condensation from C20 to C22, the last elongation step for DHA biosynthesis, was catalyzed by the KSC domain in DHA synthase. KSC domains therefore determine the chain lengths. 相似文献
8.
The digestion rates of microalgal (docosahexaenoic acid, DHA, 56.8%; palmitic acid, 22.4%), fish (DHA, 10.8%; eicosapentaenoic acid, EPA, 16.2%), and soybean oils (oleic, 21.7%; linoleic acid, 54.6%) were compared by coupling the in vitro multi-step and in vivo apparent digestion models using mice. The in vitro digestion rate estimated based on the released free fatty acids content was remarkably higher in soybean and fish oils than in microalgal oil in 30 min; however, microalgal and fish oils had similar digestion rates at longer digestion. The in vivo digestibility of microalgal oil (91.49%) was lower than those of soybean (96.50%) and fish oils (96.99%). Among the constituent fatty acids of the diet oils, docosapentaenoic acid (DPA) exhibited the highest digestibility, followed by EPA, DHA, palmitoleic, oleic, palmitic, and stearic acid, demonstrating increased digestibility with reduced chain length and increased unsaturation degree of fatty acid. The diet oils affected the deposition of fatty acids in mouse tissues, and DHA concentrations were high in epididymal fat, liver, and brain of mice fed microalgal oil. In the present study, microalgal oil showed lower in vitro and in vivo digestibility, despite adequate DHA incorporation into major mouse organs, such as the brain and liver. 相似文献
9.
Igarashi T Aursand M Sacchi R Paolillo L Nonaka M Wada S 《Journal of AOAC International》2002,85(6):1341-1354
A high-resolution proton nuclear magnetic resonance (NMR) method for determining the concentration (mg/g) of docosahexaenoic acid (DHA), the molar proportion (mol%) of DHA, and the molar proportion of total n-3 fatty acids in fish oils was validated by an IUPAC interlaboratory study (the Commission VI-6 on Oils, Fats, and Derivatives WG 3/98). Thirteen laboratories from 5 countries tested 6 pairs of blind duplicate fish oils: a refined tuna oil, 2 extracted tuna oils, an extracted bonito oil, an extracted salmon oil, and an extracted sardine oil ranging from 9 to 30 mol% DHA and from 20 to 35 mol% n-3 fatty acids. Before 1 D-proton NMR measurements with 300-500 MHz instruments, oil samples were weighed and diluted with deuterochloroform solution containing ethylene glycol dimethyl ether as internal standard. To achieve precise performance, a detailed procedure for signal area measurement was described in the protocol, and all participants were instructed about the critical importance of following the protocol. Statistical performances with invalid and outlier data removed were as follows: repeatability relative standard deviations (RSDr) ranged from 0.91 to 2.62% and reproducibility relative standard deviation (RSDR) ranged from 1.73 to 4.27% for DHA concentration (mg/g); RSDr ranged from 0.39 to 2.06%, and RSDR ranged from 0.59 to 3.46% for mol% DHA; RSDr ranged from 0.23 to 0.90% and RSDR ranged from 0.85 to 2.01 % for mol% total n-3 fatty acids. The method is expected to be recommended by IUPAC. 相似文献
10.
Biodiesel fuel production by the transesterification reaction of soybean oil using immobilized lipase 总被引:1,自引:0,他引:1
Bernardes OL Bevilaqua JV Leal MC Freire DM Langone MA 《Applied biochemistry and biotechnology》2007,137(1-12):105-114
The enzymatic alcoholysis of soybean oil with methanol and ethanol was investigated using a commercial, immobilized lipase (Lipozyme RMIM). The effect of alcohol (methanol or ethanol), enzyme concentration, molar ratio of alcohol to soybean oil, solvent, and temperature on biodiesel production was determined. The best conditions were obtained in a solvent-free system with ethanol/oil molar ratio of 3.0, temperature of 50 degrees C, and enzyme concentration of 7.0% (w/w). Three-step batch ethanolysis was most effective for the production of biodiesel. Ethyl esters yield was about 60% after 4 h of reaction. 相似文献
11.
12.
Arachidonic acid (ARA) and eicosapentaenoic acid (EPA) were produced by Pythium irregulare fungus using soybean cotyledon fiber and soy skim, two co-products from soybean aqueous processing, as substrates in different fermentation systems. Parameters such as moisture content, substrate glucose addition, incubation time, and vegetable oil supplementation were found to be important in solid-state fermentation (SSF) of soybean fiber, which is to be used as animal feed with enriched long-chain polyunsaturated fatty acids (PUFA). Soybean fiber with 8 % (dwb) glucose supplementation for a 7-day SSF produced 1.3 mg of ARA and 1.6 mg of EPA in 1 g of dried substrate. When soy skim was used as substrate for submerged fermentation, total ARA yield of 125.7 mg/L and EPA yield of 92.4 mg/L were achieved with the supplementation of 7 % (w/v) soybean oil. This study demonstrates that the values of soybean fiber and soy skim co-products could be enhanced through the long-chain PUFA production by fermentation. 相似文献
13.
Seulah Lee Man Hyung Koo Dong-Won Han Il-Chan Kim Jun Hyuck Lee Jeong-Hoon Kim Razia Sultana Sun Yeou Kim Ui Joung Youn Jin-Hyoung Kim 《Molecules (Basel, Switzerland)》2022,27(14)
Total fatty-acid (FA) contents of different organs (stomach, liver, brain, and skin) of two Antarctic fish, marbled rockcod (Notothenia rossii) and mackerel icefish (Champsocephalus gunnari), were examined using gas chromatography–mass spectrometry (GC–MS). N. rossii possessed higher contents of total omega-3, where eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), the most represented omega-3 FAs, were distributed throughout all parts of the fish. The highest level of EPA was observed in the skin and that of DHA was observed in the brain of N. rossii. C. gunnari showed organ peculiarity in that most of the omega-3 FAs were found in stomach and skin. Specifically, the highest levels of EPA and DHA were both observed in the stomach. Although N. rossii and C. gunnari both inhabit the Antarctic Southern Oceans, their characteristics in terms of the composition of fatty acids were shown to vary. The extracts were also evaluated for matrix metalloproteinase-1 (MMP-1)-inhibitory activities in UVB-induced human dermal fibroblasts, where extracts of the skin and liver of N. rossii showed the most significant inhibition upon MMP-1 production. These findings provide experimental evidence that the extracts of the Antarctic fish could be utilized as bioactive nutrients, particularly in the enhancement of skin health. 相似文献
14.
15.
Paulo Bispo Irineu Batista Raul J. Bernardino Narcisa Maria Bandarra 《Applied biochemistry and biotechnology》2014,172(4):1866-1881
The increasing evidence on the differential biochemical effects of eicosapentaenoic acid (EPA)/docosahexaenoic acid (DHA) raises the need of n-3 highly unsaturated fatty acid concentrates with different amounts of these fatty acids. In the present work, physicochemical and enzymatic techniques were combined to obtain acylglycerols, mainly triacylglycerols (TAG), rich in n-3 fatty acids. Sardine oil was obtained by washing sardine (Sardina pilchardus) mince with a NaHCO3 solution, hydrolyzed in a KOH–ethanol solution, and concentrated with urea. The esterification reaction was performed in the stoichiometric proportion of substrates for re-esterification to TAG, with 10 % level of Rhizomucor miehei lipase based on the weight of substrates, without any solvent, during 48 h. This procedure led to approximately 88 % of acylglycerols, where more than 66 % were TAG and the concentration of n-3 fatty acids was higher than 60 %, the EPA and DHA ratio (EPA/DHA) was 4:1. The content of DHA in the unesterifed fraction (free fatty acids) increased from 20 to 54 %, while the EPA level in the same fraction decreased from 33 to 12.5 % (EPA/DHA ratio ≈1:4). Computational methods (density functional theory calculations) have been carried out at the B3LYP/6-31G(d,p) level to explain some of the experimental results. 相似文献
16.
Fournier V Destaillats F Hug B Golay PA Joffre F Juanéda P Sémon E Dionisi F Lambelet P Sébédio JL Berdeaux O 《Journal of chromatography. A》2007,1154(1-2):353-359
Long-chain polyunsaturated fatty acids (LC-PUFAs) of the n-3 series and especially eicosapentaenoic and docosahexaenoic acids (EPA and DHA, respectively) have important biological properties. The main dietary sources of LC-PUFAs are fish and fish oil. Geometrical isomerization is one of the main reactions happening during the thermal treatment of polyunsaturated fatty acids. Refined fish oils are used to supplement food products in LC-PUFAs and the quality of these nutritional ingredients have to be controlled. In the present study, a suitable method for the quantification of EPA and DHA geometrical isomers in fish oils by gas-liquid chromatography (GC) is presented. A highly polar capillary column (CP-Sil 88, 100 m) operating under optimal conditions was used. Method selectivity was studied by GC-mass spectrometry. The performance characteristics of the quantification method were studied using samples of fish oil deodorized at 220 degrees C for 3 h. The linearity of the method was assessed by analyzing composite samples obtained by mixing fish oil deodorized at 220 degrees C with semi-refined fish oil (control). Precision was evaluated by analyzing the same samples in triplicate. Results showed that the validated method is suitable to quantify low amounts of geometrical (trans) isomers of EPA and DHA in refined fish oils. The limits of quantification of the EPA and DHA geometrical isomers are 0.16 and 0.56 g/100 g of fish oil, for EPA and DHA, respectively. Commercially available LC-PUFA oil samples were evaluated by using the validated method. The results show that the oils analyzed contain low amounts (<1% of total fatty acids) of geometrical isomers of EPA and DHA. 相似文献
17.
Neuhaus W Novalin S Klimacek M Splechtna B Petzelbauer I Szivak A Kulbe KD 《Applied biochemistry and biotechnology》2006,134(1):1-14
Biodiesel (fatty acid methyl esters) was produced by transesterification of triglycerides (triolein) present in olive oil with methanol and Novozym435. The effect of the molar ratio of methanol to triolein, semibatch (stepwise addition of methanol) vs batch operation, enzyme activity, and reaction temperature on overall conversion was determined. Stepwise methanolysis with a 3:1 methanol to triolein molar ratio and an overall ratio of 8:1 gave the best results. The final conversion and yield of biodiesel were unaffected by initial enzyme concentrations greater than 500 U/mL olive oil. The optimum reaction temperature was 60 degrees C. Comparison of conversion data between a test-tube scale reactor and a 2-L batch reactor revealed that the difference in conversion was within 10%. Experiments were also carried out with used cooking oil; the conversion with used cooking oil was slightly lower but no major differences were observed. The efficacy of Novozym435 was determined by reusing the enzyme; although the enzyme's relative activity decreased with reuse, it still retained 95% of its activity after five batches and more than 70% after as many as eight batches. 相似文献
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19.
Hiroki Matsuzaka Hiroki Matsuyama Wataru Tanaka Hayato Tajiri Hiroyuki Sakakibara 《Molecules (Basel, Switzerland)》2022,27(4)
Diets with high daily fat consumption are associated with excess weight. However, the effects of fat type and consumption timing on excess weight remain unclear. We investigated the selection of a 30% (w/w) fat diet of soybean oil (SOY), lard (LARD), and fish oil (FISH) on the metabolic parameters of mice. Male C57BL/6 mice were divided into the double SOY-box (w-SOY), SOY-box/LARD-box (SOY-vs-LARD), or SOY-box/FISH-box (SOY-vs-FISH) groups and allowed to selectively consume for 8 weeks. The total energy intake was similar for all groups, but the mice selectively chose to consume LARD over SOY and SOY over FISH. Body weight in the SOY-vs-LARD group was significantly higher than that in the w-SOY and SOY-vs-FISH groups. Additionally, minimal but selective consumption of an omega-3 fatty-acid-rich FISH diet at the end of the active period increased the physiological fatty acid compositions of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the SOY-vs-FISH group; their metabolic parameters were also lower than the SOY-vs-LARD group. In conclusion, selectively consuming small amounts of fish oil at the end of the day may prevent excess weight compared with LARD consumption. 相似文献
20.
Le PM Fraser C Gardner G Liang WW Kralovec JA Cunnane SC Windust AJ 《Analytical and bioanalytical chemistry》2007,389(1):241-249
Long-chain polyunsaturated fatty acids (LCPUFA) including eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA,
22:6n-3) have become important natural health products with numerous proven benefits related to brain function and cardiovascular
health. Not only are omega-3 fatty acids available in a plethora of dietary supplements, but they are also increasingly being
incorporated as triglycerides into conventional foods, including bread, milk, yoghurt and confectionaries. Recently, transgenic
oil seed crops and livestock have been developed that enhance omega-3 fatty acid content. This diverse array of matrices presents
a difficult analytical challenge and is compounded further by samples generated through clinical research. Stable isotope
13C-labelled LCPUFA standards offer many advantages as research tools because they may be distinguished from their naturally
abundant counterparts by mass spectrometry and directly incorporated as internal standards into analytical procedures. Further,
13C-labelled LCPUFAs are safe to use as metabolic tracers to study uptake and metabolism in humans. Currently, 13C-labelled LCPUFAs are expensive, available in limited supply and not in triglyceride form. To resolve these issues, marine
heterotrophic microorganisms are being isolated and screened for LCPUFA production with a view to the efficient biosynthetic
production of U-13C-labelled fatty acids using U-13C glucose as a carbon source. Of 37 isolates obtained, most were thraustochytrids, and either DHA or omega-6 docosapentaenoic
acid (22:5n-6) were produced as the major LCPUFA. The marine protist Hyalochlorella marina was identified as a novel source of EPA and omega-3 docosapentaenoic acid (22:5n-3). As proof of principle, gram-level production
of 13C-labelled DHA has been achieved with high chemical purity ( >99%) and high 13C incorporation levels (>90%), as confirmed by NMR and MS analyses. Finally, U-13C-DHA was enzymatically re-esterified to glycerol to yield a 13C-labelled tridocosahexaenoin. 相似文献