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1.
δ-Lactones derived from meadowfoam (Limnanthes) fatty acids were reacted with amine and alcohol nucleophiles in a second-order reaction to provide the acyclic 5-hydroxy eicosanoic acid esters and amides. The rate of reaction for the ring opening of δ-lactones was compared to the rate of ring opening of γ-lactones and the rate of derivatization of meadowfoam fatty acids. δ-Lactones showed a much larger rate for the formation of derivatives than the corresponding γ-lactones or fatty acids. γ-Lactone had a rate constant >7700 times larger for the formation of butyl ester than meadowfoam fatty acids. The formation of amides from δ-lactones is even faster than the esterification reaction and requires no catalyst or solvent when conducted at the melting point of the lactone.  相似文献   

2.
The lipase‐catalyzed hydrolysis of castor, coriander, and meadowfoam oils was studied in a two‐phase water/oil system. The lipases from Candida rugosa and Pseudomonas cepacia released all fatty acids from the triglycerides randomly, with the exception of castor oil. In the latter case, the P. cepacia lipase discriminated against ricinoleic acid. The lipase from Geotrichum candidum discriminated against unsaturated acids having the double bond located at the Δ‐6 (petroselinic acid in coriander oil) and Δ‐5 (meadowfoam oil) position or with a hydroxy substituent (ricinoleic acid). The expression of the selectivities of the G. candidum lipase was most pronounced in lipase‐catalyzed esterification reactions, which was exploited as part of a two‐step process to prepare highly concentrated fractions of the acids. In the first step the oils were hydrolyzed to their respective free fatty acids, in the second step a selective lipase was used to catalyze esterification of the acids with 1‐butanol. This resulted in an enrichment of the targeted acids to approximately 95—98% in the unesterified acid fractions compared to the 70—90% content in the starting acid fractions.  相似文献   

3.
Mono- and polyestolides, made from oleic acid, meadowfoam oil fatty acids and erucic acid, were subjected to biodegradation with mixed cultures of Penicillium verucosum, Mucor racemosus, and Enterobacter aerogenes. Fermentations were continued for 3, 5, 10, 15, 20, or 30 d. Meadowfoam oil and its fatty acids, oleic acid and soybean oil were also biodegraded under the same conditions. After 10 d, oleic acid and soybean oil were degraded 99.8 and 99.2%, respectively; meadowfoam oil and its fatty acids were degraded 89.0 and 97.7%, respectively. After 30 d, oleic acid-derived poly- and monoestolides were degraded 98.6 and 90.0%, respectively, meadowfoam estolides were degraded 75.7%, and erucic acid estolides were degraded 84.0%.  相似文献   

4.
The formation of estolides was detected during the studies on dimerization of meadowfoam oil fatty acids. By adjusting the reaction conditions, it was possible to produce monoestolides with little dimer or trimer formations. Estolides have potential use in lubricant, cosmetic and ink formulations and in plasticizers. This paper reports the conditions for production of estolides from mixed meadow-foam fatty acids, commercial oleic acid, high-oleic sun-flower oil fatty acids,cis-5,cis-13-docosadienoic acid, petroselinic acid and linoleic acid.  相似文献   

5.
Meadowfoam dimer acids have been prepared in a thermal clay-catalyzed reaction. Reaction conditions have been optimized, and yields of 44% were obtained with 2% water and 6–8% of an acid-washed montmorillonite clay, based on the meadowfoam fatty acids. Purity of the distilled dimer acids was 79–89% with most of the remaining 11–22% being residual mono- and tribasic acids. Dimethyl, di-(2-ethylhexyl), and di-n-butyl meadowfoam dimer ester derivatives were also prepared. Color, viscosity, and wear-preventive characteristics of the meadowfoam dimer acids and dimer ester derivatives were compared to those of commercial dimer acids and dimer esters. The viscosity of the meadowfoam dimer acids is similar to that of Empol® 1010, which is also derived from a highly monounsaturated fatty acid source. Viscosities of the meadowfoam dimer esters were also comparable to those of commercial dimer esters. Wear prevention characteristics, as determined by the four-ball test method, of the meadowfoam dimer acids and dimer esters were similar to those of the commercial products. In one case, the di-n-butyl esters, the meadowfoam derivative showed a significantly smaller wear scar than that shown by the di-n-butyl derivative of Unidyme® 14.  相似文献   

6.
Chloroalkoxy substituted C20 and C22 fatty acids can be synthesized from the unsaturated fatty acids in meadow-foam oil by reaction of the fatty acids with primary or secondary alcohols and an aqueous sodium hypochlorite solution (commercial bleach). The reactions are conducted at room temperature for 3 h. Chlorohydroxy fatty acid derivatives are formed as by-products owing to the presence of water in the reaction mixture. Chlorinated δ-lactones are also produced by direct reaction of sodium hypochlorite with the Δ5 unsaturated fatty acids present in meadowfoam or by ring closure of the 6-chloro-5-hydroxy fatty acids. The product yield of chloroalkoxy fatty acids is dependent on the nature and volume of the alcohol used in the reaction, as well as the concentration and pH of the sodium hypochlorite solution. Primary alcohols such as methanol and butanol produce maximal yields (50–60%) of chloroalkoxy fatty acids whereas the secondary alcohol 2-propanol gives a 30% yield. Chloroalkoxy fatty acid yields can be increased to 75–80% by elimination of water from the reaction mixture through a procedure that partitions sodium hypochlorite from water into hexane/ethyl acetate mixtures. All of the reaction products were fully characterized using nuclear magnetic resonance and gas chromatography-mass spectrometry.  相似文献   

7.
Sulfated diethanolamides of fatty acids are known to be effective lime soap dispersing agents. However, their preparation from fatty acids via fatty amides requires the use of organic solvents due to the high viscosity of both fatty amides and sulfated fatty amides. This study shows that the preparation of sulfated fatty amides is relatively easy when using olive pomace oil as the raw material. The latter, is converted into sulfated fatty amides by performing the following steps: saponification, hydrolysis, esterification, amidation, and sulfation. In the final step, the mixture obtained has sufficient fluidity, due to its high linoleic acid amide content, to obviate the use of organic solvents, as usually suggested in the literature. Characterization of the product was carried out by chemical analyses, FTIR, 13C NMR, GC, and HPLC. It was shown that the yield of the amidation reaction is about 80%, and that of the sulfation reaction can exceed 100% against the pure amide (more than one sulfate group could be linked to one amide molecule). On the other hand, the Borghetty test showed that the product is an effective dispersant with a lime soap dispersing power equal to five.  相似文献   

8.
Mixed monounsaturated amides (MMA) of fatty acids from meadowfoam (Limnanthes alba) were effective slip and antiblocking agents for polyethylene films. MMA may compete with extant amides as additives for manufacture of PE films if their selling price is competitive. The MMA (79% cis-5-eicosenoic acid amides, 17% cis-5-, and cis-13-docosenoic acid amides, and 1% cis-5, cis-13-docosadienoic acid amide) required > 500 ppm but < 1000 ppm dosage to achieve high slip (coefficient of friction < 0.2) within 10 minutes of film blowing. For comparison, erucamide required < 250 ppm, oleamide required < 500 ppm, and stearamide required > 1000 ppm to give high slip levels within 10 min. Maximum antiblocking effectiveness of MMA, which developed at 1000 ppm, was equivalent to stearamide at 1000 ppm. © 1993 John Wiley & Sons, Inc.§  相似文献   

9.
This report examines the use of lipases for isolating fatty acids with Δ5 unsaturation from the seed oil ofLimnanthes alba, or meadowfoam. Seven lipase types and three enzyme configurations (immobilized, “free” and reversemicellar encapsulated) were examined. All lipases discriminated against Δ5 acids to varying degrees, but the degree of discrimination was independent of enzyme configuration. Lipase-catalyzed esterification of meadowfoam oil’s free fatty acids was much more successful for isolating Δ5 acyl groups than was lipolysis. For example, esterification directed byChromobacterium viscosum lipase yielded a free fatty acid product containing >95% of the Δ5 acyl groups at >99% purity.  相似文献   

10.
Medicago sativa cv. G98A is highly resistant to the potato leafhopper, Empoascafabae. Glandular trichome extracts from G98A were fractionated using flash chromatography and tested for settling deterrency against the potato leafhopper. A fraction of intermediate polarity exhibited strong, dose-dependent deterrency when applied to the surface of an artificial diet sachet. Deterrency was not detected, however, when the fraction was applied to the internal surface of the sachet membrane (i.e., when contact was limited to only the leafhoppers' stylets). Major components of the highly deterrent fraction, determined by gas chromatography-mass spectrometry, were a homologous series of fatty acid amides C(n)H(2n+1)NO (n = 19-23) and trace components were 12:0, 13:0, 14:0, 15:0, 16:0, 17:0, 18:0, and possibly 18:1 free fatty acids. Deterrency declined slightly, but was still strong, after fatty acids were removed from crude extracts. When the crude extracts were separated further, a fraction containing only the fatty acid amides was also deterrent. Activity increased when this fraction was supplemented with authentic (C12:0 through C18:0, and C18:1) free fatty acids. However, the authentic free fatty acids were not deterrent when tested without the lipophilic amides. Fatty acid amides and free fatty acids in trichomes of M. sativa G98A may synergize and together function in deterring settling by the potato leafhopper.  相似文献   

11.
单体酸混合物成分的GC-MS分析   总被引:2,自引:0,他引:2  
研究了生产二聚酸时得到的副产品单体酸的化学组成的GC MS分析方法,样品首先用质量浓度为140g/L KOH M eOH进行甲酯化,然后用GC MS进行分析和鉴定,共鉴定出棕榈酸、肉豆蔻酸、10甲基月桂酸、12甲基十四烷酸、十八烯酸等13种物质,总脂肪酸的质量分数占76.71%,其中饱和酸占66.36%,不饱和酸占10.35%,其中直链酸占饱和脂肪酸的41.02%,支链酸即异构酸占饱和脂肪酸的58.98%。  相似文献   

12.
Ammonolysis of fatty acids to the corresponding fatty acid amides is efficiently catalysed by Candida antartica lipase (Novozym 435). In the present paper lipase-catalysed synthesis of erucamide by ammonolysis of erucic acid and urea in organic solvent medium was studied and optimal conditions for fatty amides synthesis were established. In this process erucic acid gave 88.74 % pure erucamide after 48 hour and 250 rpm at 60 degrees C with 1:4 molar ratio of erucic acid and urea, the organic solvent media is 50 ml tert-butyl alcohol (2-methyl-2-propanol). This process for synthesis is economical as we used urea in place of ammonia or other amidation reactant at atmospheric pressure. The amount of catalyst used is 3 %.  相似文献   

13.
A series of fatty acid amides derived from (R)‐ and (S)‐ricinoleic acid and 4 cyclic and acyclic amines were synthesized in a proecological solvent‐free process with yields ranging from 43 to 88%. All S‐configured compounds and both enantiomers of amide with 2‐amino‐2‐methyl‐1‐propanol were obtained and studied in terms of biological activity for the first time. The evaluation of antimicrobial activity of (R)‐ and (S)‐ricinoleic acid derivatives against 13 different microorganisms representing Gram‐negative and Gram‐positive bacteria, yeast, and molds showed significant inhibitory activity against Gram‐positive bacteria, especially Micrococcus luteus and Bacillus subtilis, and against selected molds. Ethanolamine‐ and pyrrolidine‐derived amides showed the most promising antibacterial and antimold potential. Derivatives from ricinoleic acid and pyrrolidine were the most active against both selected molds, Aspergillus brasiliensis and Penicillium expansum. Moreover, the R‐configured analog was the most potent against B. subtilis. The amides of ricinoleic acid with ethanolamine exhibited significant potential to Staphylococcus aureus, which distinguished them from the rest of tested derivatives to which this bacterium was very resistant.  相似文献   

14.
Fatty acids are widely used in industries for various applications as soaps or in their crystalline form. Fatty acid soaps are used as surface-active agent to stabilize foams and emulsions, for detergency, and surface wetting. Fatty acid molecules in organic solvents are used as low-molecular-mass organic gelators. Currently, there is a renewed interest in using fatty acids in industrial applications instead of petrochemical surfactants since fatty acid soaps are green surfactants. Fatty acids exhibit also many advantages, including the design of responsive soft-materials. Fatty acid soaps are natural pH and thermoresponsive surfactants, which can lead to responsive foams and emulsions. In their crystalline form, fatty acid crystals in both aqueous and non-aqueous solvents stabilize liquid foams. These crystals are also efficient in the production of liquid marbles. Fatty acids are solvosurfactants with the ability to form microemulsions and capillary suspensions. In this review, we illustrate how fatty acid molecules can be used in the manufacture of multiresponsive soft-materials ranging from aqueous and non-aqueous foams, emulsions, nanoemulsions, microemulsions, liquid marbles and capillary suspensions.  相似文献   

15.
The objective of this study was to develop scaleup bioprocesses for producing 10-hydroxystearic acid (10-HSA) and 10-ketostearic acid (10-KSA) as well as their primary amides for potential new uses. A reactor process was examined to obtain the mono-oxygenated FA using Sphingobacterium thalpophilum (NRRL B-14797) and Bacillus sphaericus (NRRL NRS-732), which solely produce 10-HSA and 10-KSA, respectively, from technical-grade oleic acid. By using an 8-h-old B-14797 culture grown in a manganese-containing WF6 medium, pH 7.3, at 28°C under 350 rpm agitation and 0–50% dissolved oxygen concentrations provided by a controlled sparger aeration, the production of 10-HSA reached 7 g/L with a 40% yield in 4 d. In using a 12-h-old NRS-732 culture grown in a pyruvate-containing PF6 medium, pH 6.5, at 30°C under 750 rpm agitation without any sparger aeration during the conversion reaction, 10-KSA production reached 7.9 g/L with a yield of more than 54% in 72 h. The scaleup reactor process provided crystalline 10-HSA and 10-KSA for producting new primary amides via a lipase-catalyzed amidation reaction with yields of 94 and 92%, respectively. The primary amides of 10-HSA and 10-KSA displayed m.p of 115 and 120°C, respectively.  相似文献   

16.
The biodiesel that is considered as a possible substitute or extender of conventional automotive diesel fuel is commonly composed of fatty acid methyl esters that are prepared from the glycerides in vegetable oils by transesterification with methanol. This form of biodiesel is compatible with diesel fuel but offers no improvement in its ignition quality. This work describes the results of a series of experiments aimed at assessing other common fatty acid derivatives that could provide the desired biofuel component and, at the same time, improve the performance of the fuel. It was found that tertiary fatty amines and amides are significantly more effective than methyl esters in enhancing the ignition quality of the finished diesel fuel without having any negative effect on its cold flow properties.  相似文献   

17.
Estolides are condensed oligomers of fatty acids made by introducing an ester linkage at sites of unsaturation. Estolides made from meadowfoam (Limnanthes alba) oil fatty acids have positive effects in personal care formulations and a patent has been applied for. However, estolides prepared by acid catalysis had a color of 12 (Gardner scale) and industrial cooperators desired lower color to increase marketability of meadowfoam estolides. Hydrogen peroxide and hydrogenation did not lower the color of estolide but 1% w/w sodium borohydride at 80°C for 12 h reduced color to 7 on the Gardner scale which was acceptable to the industrial partners for further development. Sodium borohydride decolorization gives a product with good color at a reasonable cost. The sodium borohydride does not have to be used in concentrations higher than 1% w/w and the product loss, which can be several percent with a clay-based process, is negligible using sodium borohydride.  相似文献   

18.
油酸的精制研究   总被引:5,自引:1,他引:4  
油酸酰胺是一种很好的塑料添加剂 ,可用作塑料加工成型时的脱膜剂、润滑剂。油酸的原料来源很广 ,牛油、羊油、猪油等动物油油脂以及大豆油、花生油、棕榈油等植物油脂中都含有大量的油酸。由于油酸的来源和生产方法多种多样 ,因此其所含的脂肪酸种类及含量都不尽相同。除油酸外 ,还有亚油酸、亚麻酸等高不饱和脂肪酸。针对油酸中因含有大量的多不饱和组分如亚油酸、亚麻酸而容易产生氧化泛黄的问题 ,采取了尿素络合法对原料油酸进行精制 ,以减少原料中亚油酸、亚麻酸组分的含量。经气相色谱验证 ,产品达到了应用指标 ,提高了产品的抗氧性。  相似文献   

19.
Estolide production with modified clay catalysts and process conditions   总被引:1,自引:0,他引:1  
The 20% yields of estolides prepared from oleic acid and meadowfoam oil fatty acids are improved when the montmorillonite clay catalysts are modified to increase their activity. Changes we explored included acidifying the clay, treating to increase the surface area of clay to introduce new active sites, and decreasing the ionic character of the clay surface to enhance adsorption of the fatty acids. We also evaluated the use of higher levels of clay in the reactions. Clays treated with Fe3+ salts increase the estolide yield from 21 to 27%, a 28% increase. Clay catalysts were also treated with surface-active reagents. The most active were cationic surfactants, and montmorillonite clays treated with cetyltrimethylammonium chloride increased the estolide yield to 30%. Estolide yields could not be improved beyond 30% by increasing the amount of clay. However, nitrogen sparging increases the efficiency of stirring and increased the estolide yield to 35% estolide.  相似文献   

20.
The monomers produced from thermal high-pressure conversion of meadowfoam or oleic acids into estolides were characterized as a complex mixture of fatty acids. Mild reaction conditions produced little change in the starting acids. However, vigorous reaction conditions,e.g. ≥3 h at 250°C with stirring, significantly altered the starting fatty acids.Cis/trans isomerization occurred readily, with the proportion oftrans isomers reaching 57%. In addition, the double bonds migrated throughout all positions of the hydrocarbon chain with concentrations diminishing outward from the starting double bond position. Branching was also observed to a small extent under these conditions and was even more pronounced in the absence of water. Lactones were also identified in the reaction mixture, with contents near 16% in the meadowfoam series. All products can be explainedvia carbocation rearrangement mechanisms that result from protonation of the starting olefins.  相似文献   

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