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1.
Kim KH  Choi SU  Lee KR 《Lipids》2012,47(6):593-599
A bioassay-guided fractionation and chemical investigation of a MeOH extract of the Korean wild mushroom Boletus pseudocalopus resulted in the identification of three new fatty acid esters, named calopusins A-C (1-3), along with two known fatty acid methyl esters (4-5). These new compounds are structurally unique fatty acid esters with a 2,3-butanediol moiety. Their structures were elucidated through 1D- and 2D-NMR spectroscopic data and GC-MS analysis as well as a modified Mosher's method. The new compounds 1-3 showed significant inhibitory activity against the proliferation of the tested cancer cell lines with IC(50) values in the range 2.77-12.51 μM.  相似文献   

2.
固定化Candida sp.99-125脂肪酶催化大豆油合成脂肪酸乙酯   总被引:1,自引:0,他引:1  
探讨了酶法合成脂肪酸乙酯作为生物柴油的可行性. 以大豆油和乙醇为原料,利用本实验室自制的固定化Candida sp. 99-125脂肪酶催化反应,深入研究水含量、溶剂量、脂肪酶量及反应温度等因素对酶法合成脂肪酸乙酯的影响. 结果表明,以大豆油质量为基准,在水含量为 12.5%(w)、溶剂正己烷为3 mL/g、脂肪酶量为20%(w)、温度40℃的优化反应条件下,3次流加乙醇,170 r/min摇瓶反应,12 h后可以达到96.8%的最高酯得率. 进一步研究表明,在此优化反应条件下,连续使用14批脂肪酶酯得率可保持70%以上.  相似文献   

3.
4.
The non-edible crude rice bran oil was extracted from white rice bran, and then was catalyzed by immobilized lipase for biodiesel production in this study. The effects of water content, oil/methanol molar ratio, temperature, enzyme amount, solvent,number of methanol added times and two-step methanolysis by using Candida sp. 99-125 as catalyst were investigated. The optimal conditions for processing 1 g rice bran oil were: 0.2 g immobilized lipase, 2 ml n-hexane as solvent, 20% water based on the rice bran oil mass, temperature of 40 °C and two-step addition of methanol. As a result, the fatty acid methyl esters yield was 87.4%. The immobilized lipase was proved to be stable when it was used repeatedly for 7 cycles.  相似文献   

5.
研究以废油酯为原料在固体酸催化作用下与丁醇酯交换反应制备脂肪酸丁酯的过程,采用气相色谱对脂肪酸丁酯的含量进行分析。考察了醇油摩尔比、催化剂用量、反应温度和反应时间对酯化反应转化率的影响。结果表明,该反应的最适宜工艺条件为:醇油摩尔比16∶1,催化剂用量1.2%,反应温度115℃,反应时间4 h。废油酯在最优工艺条件下,经过酯交换反应得到的转化率超过83%。  相似文献   

6.
Free and esterified ergosterols are detected almost solely in fungi and are often employed as a biomarker of living fungi. In this work, the fatty acid composition and δ13C values of major fatty acids in triglycerides and ergosteryl esters from the fungus Ganoderma lucidum were analyzed by gas chromatography–mass spectrometer and gas chromatography–isotopic ratio mass spectrometer, respectively. The results showed that the fatty acid profiles varied in triglycerides and ergosteryl esters. The percentage of saturated fatty acids in ergosteryl esters was remarkably higher than that in triglycerides, where C18:1Δ9c was the predominant fatty acid and constituted 61.26 % of the total fatty acids. In contrast, C16:0 was the predominant fatty acid and constituted 71.88 % of the total fatty acids in ergosteryl esters. The study suggests that, after fungal death, free ergosterols in the cell membrane of the dead fungus were esterified with preferentially saturated fatty acids, mainly C16:0, from triglycerides and then stored in lipid particles for a longer period while free ergosterol markedly decreased. The δ13C values of C16:0, C18:0, C18:1 and C18:2 in ergosteryl esters exhibit a pronounced depletion in 13C compared with that in triglycerides within the range of ?1.3 to ?0.9 ‰, supporting the above inference. It is again suggested that free ergosterol in the cell membrane should be used as an indicator of living fungi, and ergosteryl esters in the lipid particles should not be included in the measurement of living fungal biomass.  相似文献   

7.
聚甘油脂肪酸酯的合成应用与市场开发   总被引:5,自引:0,他引:5  
本文介绍了聚甘油脂肪酸的组成,性能,合成工艺及其在食品乳化剂等领域的应用,指出了该产品广阔的发展前景。  相似文献   

8.
The current work has shown the potentials for the aerobic oxidation of fatty acid methyl ester (FAME) of vegetable oils in the production of polyvinylchloride (PVC) plasticizers with the exclusion of other reagents. The reaction mixtures contain epoxidized derivatives of FAME, and esters, with the quantity of the ester groups being higher than in the initial raw material. It was established that the increase in the additional ester groups resulting from the “aerobic” Baeyer-Villiger (BV) reaction has a significantly positive influence on the plasticizing ability of the oxidized FAME mixtures for PVC when compared to the formation of epoxide compounds. The development of the technology for the production of PVC plasticizers proposed in this investigation provides an opportunity for resolving some of the environmental issues normally associated with the use of phthalate-based plasticizers.  相似文献   

9.
Rada Malko  Isabel Larraza 《Lipids》2019,54(11-12):715-723
Growing health awareness has resulted in the increased use of dietary supplements derived from plants and marine sources, leaving consumers unsure of their best options. There were three objectives of the present study. The first was to design and evaluate an efficient derivatization procedure. The second was to perform a comparative analysis of liquid oils and their corresponding capsules of hemp, chia, and flax seeds. The final objective was to determine the fatty acid (FA) composition of six fish oil products and compare it to the one provided on the label. For the FA profiling, we implemented two efficient, one-step, sustainable methods with high percentage recovery for the synthesis of FA methyl esters (FAME), which use base catalysis and microwave-assisted heating. Our results found no difference in nutritional value between liquid oils and capsules of the seed supplements, with flaxseed and chia offering a higher, beneficial n-3:n-6 ratio compared to hemp oil. Four of the fish oils analyzed contained significantly less eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) than their reported label, and the other two not only agreed with the manufacturers' declaration but were able to fulfill the daily adequate intake (AI) with fewer capsules.  相似文献   

10.
Hydroxy sulfonated fatty acid ester surfactants, having the general formula RCOOCH2CHOHCH2SO3M (where M is alkali or other metal) have been synthesized from four saturated (C12 to C18) and four unsaturated (C18?, C182?, C183? and ricinoleic) fatty acids. Comparative evaluation of their surface active properties as well as some analytical methods for determining their composition and their identification and separation have been described.  相似文献   

11.
脂肪酸甲酯磺酸盐(MES)是以天然油脂为原料,经磺化、中和、老化等工艺制得,是一类新型、性能优良、可再生的阴离子表面活性剂。由于MES具有优异的理化性能,如表面活性、洗涤性能、配伍性能、泡沫性能、钙皂分散性等,越来越多的科学工作者对MES的理化性能进行了研究,同时也有较多的研究关于MES在日用化工领域以及其他领域的应用,但因为MES的生产工艺复杂,常常会因为产品的色泽和二钠盐问题限制了MES的推广。结合工厂生产实际,简述了MES的磺化反应机理和生产关键控制,综述了MES的理化性能研究和在工业领域的应用。  相似文献   

12.
In the present work, the measured cetane numbers (CN) of pure fatty acid methyl esters (FAME), as well as the FAME compositions and the reported CN of 59 kinds of biodiesels collected from literature were used to develop a simple model involving as more FAME component as possible for predicting CN of biodiesel from its FAME composition. Two different regression equations correlating the CN of pure FAME with the carbon number of fatty acid chain were obtained by regression analysis, which shows that the dependence of the CN on the carbon number varies with the unsaturated degree of fatty acid chain. The 59 biodiesels were divided into two categories and used, respectively to develop and test a multiple linear regression model (MLRM) correlating the CN of biodiesel with its FAME composition. A simple and convenient regression equation with a high accuracy and a good reproducibility (average absolute error of 0.49 CN for testing set and 1.52 CN for all data) were developed, showing excellent correlation (R 2: 0.9904 for testing set). The model developed in the present work can be used conveniently to give a satisfactory predicted CN of biodiesel from the FAME composition.  相似文献   

13.
The glycerolysis of methyl ester was investigated in flow reactors. This reaction represents a liquid two-phase reaction with changing reaction rates in a batch reactor. A semi-empirical model tested earlier with batch reactor data was used to simulate different continuous processes for this reaction. Among the processes simulated, a single continuous-flow stirred tank reactor (CSTR) without recycling was considered most appropriate for experimental implementation, although simulations showed that a faster reaction rate is possible with the application of a CSTR followed by a tubular reactor with certain associated residence times. The CSTR simulations were verified experimentally. A good agreement was found between the experimental data and simulation results.  相似文献   

14.
Waste mixed seashells of Perna viridis, Anadara granosa, Amusium pleuronectes, and Meretrix meretrix, as abundant, low-cost, and nontoxic calcium sources, were used as renewable raw materials in the preparation of a heterogeneous base catalyst for the transesterification of palm oil in refluxed methanol. The new mixed metal compound catalyst was prepared by mixing the calcined seashells with Zn(NO3)2 and Al2O3 in an acidic aqueous solution, followed by calcination at 500°C (ZSA-500). The ZSA-500 catalyst exhibited an enhanced surface area, dispersion, and total basicity compared to the parent calcined seashells. The fatty acid methyl ester (FAME) yield attained over ZSA-500 was 99 wt.% and dropped by 3% after five repetitive uses when the reaction was performed for 3 h at 60°C and ambient pressure with 10 wt.% catalyst and a methanol:oil molar ratio of 30:1. Structural and thermal analysis indicated that the active phases of ZSA-500 had a high stability against the glycerol adsorption as well as the phase transformation to calcium glyceroxides (Ca(C3H7O3)2).  相似文献   

15.
A novel tetrahydrofuranyl fatty acid (THFA) and a rare natural (R)-configuration phenylethanediol were isolated from potato extract media in which Pestalotia sp. YIM 69032 had been cultivated. On the basis of spectral data including of HRMS, NMR and 2D NMR, their structures were determined as (3R,5S,6R,7S,8Z)-8-en-5,7-dihydroxy-3,6-epoxy-tetradecanoic acid (1) and (R)-1-(3-ethylphenyl)-1, 2-ethanediol (2). Thus, a new microbial isolate, Pestalotia sp. was found to produce THFA. The possible pathway from tetradecanoic acid (4) to THFA (1) in the extract of potato by Pestalotia sp. was proposed. Structures 1 and 2 showed no cytotoxicity against HL-60, SMMC-7721, A-549, MCF-7, SW480 cell lines.  相似文献   

16.
We are presenting our results on the alkylaluminium halide catalyzed ene addition of formaldehyde to readily available unsaturated fatty compounds to give primary homoallylic alcohols. The reaction of oleic acid and 10-undecenoic acid with formaldehyde gives (E)-9(10)-(hydroxymethyl)octadec-10(8)-enoic acid and 12-hydroxydodec-9-enoic acid, respectively, in high yields. Formaldehyde can be added also to oleyl alcohol to give the very interesting diol (E)-9(10)-(hydroxymethyl)oxtadec-10(8)-en-l-ol. Me2AlCl and EtAl-sesquichloride are the most suitable catalysts for these reactions. The addition of formaldehyde to methyl oleate and methyl 10-undecenoate, respectively, to give the corresponding ene products is catalyzed by EtAlCl2.  相似文献   

17.

Abstract  

The hydrophobation of rosmarinic acid with saturated aliphatic primary alcohols of various chain lengths (methanol to eicosanol) was achieved via an acid-catalyzed esterification in the presence of a highly acidic sulfonic resin. The resulting alkyl rosmarinates were isolated, characterized and their global free radical scavenging activity was determined by the 2,2-diphenyl-1-picrylhydrazyl method in the stationary state. Only the dodecyl ester showed a stronger activity than rosmarinic acid.  相似文献   

18.
The preparation and properties of a few surface-active sulfonated monoglycerides derived from fish-, rice bran- and cottonseed oils are reported.  相似文献   

19.
In the present study, we investigated the production of fatty acid methyl esters (FAME) from moist Chlorella sp. and Nannochloropsis oculata biomass using a hydrolysis–esterification process. Additionally, we evaluated for the first time the fatty acid profile before and after this process. Hydrolysis of the lipid fraction was performed on a moist biomass in the presence of differing amounts of an acid catalyst in both 50 and 100 % w/w water relative to the biomass. The esterification of the crude extracts of the free fatty acids (FFA) was then investigated. The experiments show that in the presence of 50 % w/w water relative to the biomass, the hydrolysis–esterification process results in higher FFA and FAME yields. The analysis of the fatty ester profiles did not reveal any degradation of the FFA from the microalgae biomass under the hydrolysis–esterification conditions. The results were compared with both extraction–transesterification and direct transesterification processes using dry biomass. The extraction–transesterification and hydrolysis–esterification processes resulted in similar FAME yields and similar profiles of the fatty esters from dry and moist biomass materials, respectively.  相似文献   

20.
Seeds of Lithospermum officinale L. from different climatic zones were analyzed for new sources of γ-linolenic acid (GLA, 18:3n-6) and stearidonic acid (SDA, 18:4n-3). Cultured Borago officinalis was also analyzed for comparative purposes. Analyses were conducted for fatty acid (FA) profiles of the glyceride oils from the seeds and in the neutral and polar lipids by gas chromatography (GC); lipid classes by open column chromatography and preparative thin layer chromatography (TLC); and tocopherols, sterols, and phenolic compounds by high-performance liquid chromatography with diode array detection (HPLC-DAD), and the later compounds were confirmed by liquid-chromatography-mass spectrometry (LC–MS). L. officinale from St. Petersburg Botanical Garden showed the highest percentage of GLA (17.9% of total FA), while wild-growing L. officinale from the Rostov region contained the highest percentage of SDA (17.2% of total FA). Total FA content ranged from 11.3 to 20.8% of seed weight. Neutral and polar lipids accounted for ~98 and 2.27%, respectively, of total lipids. Five neutral lipid classes were identified (% of NL): triterpene esters (1.3), triacylglycerols (93.1), free FA (1.8), diacylglycerols (1.4), and monoacylglycerols (2.4). The highest tocopherol content was found in samples from Chechen Republic (35.7 mg/100 g), in which the δ isomer was the main component. Samples from the Rostov region had the highest amounts of sterols (83.8 mg/100 g), and Δ5-avenasterol was the predominant compound in all samples. L. officinale seeds contain high amounts of phenolic compounds (389.9 mg/100 g as upper limit), in which rosmarinic acid is highlighted. Overall, all data suggest the possibility of using L. officinale seed oil in pharmaceutical and cosmetic formulae and as functional food.  相似文献   

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