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1.
Selim M. Erhan Robert Kleiman Terry A. Isbell 《Journal of the American Oil Chemists' Society》1993,70(5):461-465
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
2.
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
3.
Summary In this discussion we have attempted to cover pertinent factors concerning the production and applications of solid fatty
acid soaps, with particular emphasis on how the fatty acid characteristics come into play. We have avoided reference to specific
formulations because these must be kept in the realm of metallic soap manufacturers’ “know how.” Those interested in modifiers
and their effect on metallic soaps can find reference material in past issues of the Journal of American Oil Chemists’ Society
(for example, reference 9) and in the patent literature.
Reference to theoretical considerations of metallic soap structure has also been avoided as in this area the reader can again
find reference material in the Journal of American Oil Chemists’ Society (for example, reference 10). 相似文献
4.
Halina Szelag Wlodzimierz Zwierzykowski 《European Journal of Lipid Science and Technology》1998,100(7):302-307
The kinetics of the direct esterification of glycerol with fatty acids in the presence of sodium and potassium soaps, synthesized in situ to obtain modified acylglycerol emulsifiers, were investigated. The effect of temperature, soap concentration and fatty acid hydrocarbon chain length on the concentration of monoacylglycerols in the reaction mixture was examined. The kinetic studies proved that esterification of glycerol with fatty acids by our method is a first order consecutive reaction with monoacylglycerol as stable intermediate product. The corresponding rate constants and activation energies were evaluated. With the known reaction rate constants, the maximum concentration of monoacylglycerol may be calculated. It was stated that the proposed method opens up possibilities for a specific adjustment of the acylglycerol composition and, thus, of the hydrophilic-lipophilic properties and the characteristics of the emulsifier. 相似文献
5.
E. A. Emken 《Journal of the American Oil Chemists' Society》1981,58(3):278-283
Absorption and distribution of positionalcis andtrans octadecenoic acid isomers in lipids from rat, egg and human tissues are reviewed. Selected data on enzyme, single-cell, and
whole-animal studies with positional octadecenoic acid isomers are summarized and compared. 相似文献
6.
R. J. Jandacek 《Lipids》1991,26(3):250-253
The solubilization of the calcium soaps of long chain fatty acids by liquid fatty acids was observed. The solubilities of
calcium palmitate, calcium laurate, and calcium oleate were 15.6, 22.8, and 53.3 wt%, respectively, in oleic acid at 40°C.
The formation of an acid-calcium soap complex was demonstrated by x-ray diffraction studies of calcium laurate, lauric acid,
and a mixture of these compounds that had been heated. Similar evidence was obtained for a calcium oleate-oleic acid complex.
The solubility of calcium oleate in a bile salt micellar system was enhanced by obeic acid. The solubilization of calcium
soaps by liquid fatty acids may explain the unexpectedly high bioavailability of some calcium soaps. 相似文献
7.
Francis J. Licata 《Journal of the American Oil Chemists' Society》1954,31(5):204-208
Conclusion The above consideration of metallic soaps has been conducted from the point of view of the fatty acid used. It is evident
that the fatty acid does play an important function in determining the method of preparation, the physical properties, and
ultimately the use of metallic soaps.
Presented at the annual Fall Meeting, American Oil Chemists’ Society, Nov. 2–4, 1953, Chicago, Ill. 相似文献
8.
W. O. Munns S. Kairys Dilys A. Manion E. M. Meade 《Journal of the American Oil Chemists' Society》1962,39(4):189-192
The formation of acid soaps has been used successfully for the separation of a mixture of fatty acids into high and low iodine
value fractions. The acid soaps of saturated acid can be made to crystallize from water leaving their unsaturated counter
parts in solution. Acid soaps of saturated fatty acids are well characterized compounds with the formula R-COOM.R-COOH, where
R is a straight alkyl chain, and M is sodium, potassium or ammonium.
Optimum crystallization conditions involve a soap concentration of 2–5%, pH adjustment to between 7.0 and 8.0, an initial
crystallization temperature not below 25C, and a crystallization period of at least 4 hr during which time cooling to a final
temperature of 5–10C must be gradual, and agitation gentle. 相似文献
9.
10.
Transition temperatures and enthalpies and some phase diagrams of pure odd and even sodium soaps have been determined by means
of dif-ferential thermal analysis and scanning calorim-etry. Branched sodium soaps have been added for comparison.
No essential difference has been found between the number, type, and enthalpy of the transitions of the neighboring odd and
even soaps. The total enthalpy and entropy of transition are consider-ably lower than those of the corresponding par-affins
and fatty acids. The entropy of the subneat-neat and perhaps of the neat isotropic transition has an alternating character,
which suggests a different methyl end-group packing for even and odd soap. These two facts suggest that the melted soap is
still in an organized state.
Presented at the AOCS Meeting, New Orleans, May 1967. 相似文献
11.
W. D. Pohle 《Journal of the American Oil Chemists' Society》1941,18(12):244-245
Summary The solubility of calcium soaps of rosin acids and fatty acids have been determined and compared.
The solubility of calcium soaps of rosin acids (d-pimaric, dihydroabietic, and l-abietic acids) present in gum rosin was found
to be greater than that of the calcium soaps of the following saturated fatty acids: lauric, myristic, palmitic, and stearic
acids.
The calcium oleate was much more soluble than the calcium stearate.
As the amount of hydrogen in the rosin acid molecule is increased, l-abietic to dihydroabietic to tetrahydroabietic acid,
the solubility of the calcium soap is decreased.
The author wishes to express his indebtedness to Dr. G. S. Jamieson and W. G. Rose of the Agricultural Chemical Research Division
for the pure lauric, myristic, palmitic and stearic acid used in this study. 相似文献
12.
Summary A study has been made of the detergency and foaming power of soaps made from a typical acid-refined American tall oil. Sodium
soap of tall oil, straight tall oil fatty-acid soap, and straight tall oil resin-acid soap were evaluated. The effect of fatty
acid-resin acid ratio was determined by using mixtures of those soaps. Sodium rosinate, sodium oleate, and mixtures of these
soaps were used as comparison standards. Curves plotted show wash-test data and foaming values as functions of the ratio of
fatty soap to resin soap.
The data indicate in terms of detergency: a) tall oil soap has a higher value than sodium rosinate; b) sodium oleate is better
than tall oil fatty-acid soap, but the latter is approximately equivalent to soaps from various unsaturated vegetable oils;
c) both tall oil resin-acid soap and rosin soap have low detergency on cotton; d) the detergency of most mixtures of tall
oil fatty-acid and resin-acid soaps at lower concentrations is greater than would be predicted from the individual soaps,
indicating a synergistic effect.
As a rough approximation, tall oil soap without unsaponifiables is equivalent to a corresponding mixture of sodium oleate
and sodium rosinate. The presence of unsaponifiables lowers both detergency and foaming. Tall oil soap is somewhat less sensitive
to hard water than sodium oleate.
Significant differences between detergencies of soaps, and especially between soap mixtures, are obscured when launderometer
tests are run at moderate soap concentrations. These differences are readily detected at lower concentrations.
Presented at 113th meeting of the American Chemical Society, Chicago, Ill., April 14–23, 1948. 相似文献
13.
14.
Gerald P. McNeill Robert G. Ackman Stephen R. Moore 《Journal of the American Oil Chemists' Society》1996,73(11):1403-1407
Lipase hydrolysis was evaluated as a means of selectively enriching long-chain ω3 fatty acids in fish oil. Several lipases
were screened for their ability to enrich total ω-3 acids or selectively enrich either docosahexaenoic acid (DHA) or eicosapentaenoic
acid (EPA). The effect of enzyme concentration, degree of hydrolysis, and fatty acid composition of the feed oil was studied.
Because the materials that were enriched in long-chain ω3 acids were either partial glycerides or free fatty acids, enzymatic
reesterification of these materials to triglycerides by lipase catalysis was also investigated. Hydrolysis of fish oil by
eitherCandida rugosa orGeotrichum candidum lipases resulted in an increase in the content of total ω3 acids from about 30% in the feed oil to 45% in the partial glycerides.
The lipase fromC. rugosa was effective in selectively enriching either DHA or EPA, resulting in a change of either the DHA/EPA ratio or the EPA/DHA
ratio from approximately 1:1 to 5:1. Nonselective reesterification of free fatty acids or partial glycerides that contained
ω3 fatty acids could be achieved at high efficiency (approximately 95% triglycerides in the product) by using immobilizedRhizomucor miehei lipase with continuous removal of water. 相似文献
15.
Production of vegetable, animal and marine oils containing more than about 40% unsaturated fatty acids totaled 15,000 million
pounds in 1968, almost on the scale of petrochemical production. The greater share (64%) of this nonfossil oil production
was directed toward food uses, the remainder toward industrial and animal feed uses. The variety of chemical reactions carried
out on these unsaturated fatty acid products include hydrogenation, interesterification, dimerization, sulfation, formation
of nitrogen compounds, epoxidation, alkaline cleavage and oxidative ozonolysis. Some of these reactions have been developed
at Utilization Research and Development Divisions of the Agricultural Research Service, U.S. Department of Agriculture. Research
is continuing in developing new reactions for potential industrial application. An example is reductive ozonolysis of unsaturated
fatty esters to produce monofunctional aldehydes and bifunctional aldehyde esters.
Presented at the ISF-AOCS World Congress, Chicago, September 1970.
No. Market. Nutr. Res. Div., ARS, USDA. 相似文献
16.
17.
Lipid soluble fluorescent pigments from human testis were fractionated by silicic acid column chromatography and silica gel thin layer chromatography. Fluorescence analyses revealed a family of at least 3 compounds with similar fluorescence properties, including excitation and emission maxima, reversible fluorescence quenching by alkaline pH, and fluorescence quenching by heavy metal chelation. These fluorescence characteristics strongly indicated the presence of the conjugated Schiff base fluorophore-N=C-C=C-N-. The chromatographic separations employed enabled a more definitive fluorescence characterization of the lipid soluble pigments known to accumulate late in tissues with age and as a result of lipid peroxidation. Total lipids and fatty acid composition of the total lipids were determined. Polyenoic acids constituted about 40% of the total fatty acids. Histological examination of the tissues revealed some degeneration and edema, but significant spermatogenesis and normal complement of Leydig cells. 相似文献
18.
M. I. Gurr 《Lipids》1971,6(4):266-273
This paper is a review of some of the work being done at the author's laboratory. The phospholipids and glycolipids of the
alga,Chlorella vulgaris, have been implicated in fatty acid transformations such as chain elongation and desaturation. Labeling studies with [14C] acetate have shown that newly synthesized galactosyl glycerides have mainly saturated fatty acids. Subsequent to de novo
synthesis, a series of alterations of fatty acid structure takes place within the same glycolipid molecules. The specific
incorporation of [14C] oleic acid intoChlorella phosphatidyl choline provides a convenient model system for studying the lipid dependent desaturation of oleic to linoleic
acid. The inhibitor of fatty acid desaturation, sterculic acid, only inhibits the conversion of oleate into linoleate if added
before the precursor fatty acid has been incorporated into a complex lipid. Studies with isomeric monoenoic fatty acids have
suggested that there are two enzymes which catalyze the formation of linoleic from oleic acid. One measures the position of
the second double bond from the carboxyl group, the other, from the methyl end of the chain. The latter enzyme probably requires
the complex lipid substrate. 相似文献
19.
Genetically obese (ob/ob) mice display a variety of metabolic differences from lean litter mates. In the obese state, fatty
acid desaturation-elongation in brown adipose tissue mitochondria is apparently altered, resulting in differences in membrane
fatty acid composition. This change in membrane lipid environment appears to influence GDP binding and there-fore the activity
of the proton conductance pathway associated with regulation of energy expenditure in these animals. In liver, binding of
insulin to the nuclear membrane is increased by feeding a high polyunsaturated/saturated (P/S) diet fat. Consumption of a
high P/S diet decreased mRNA levels for fatty acid synthase, acetyl-CoA carboxylase, malic enzyme, and pyruvate kinase in
obese and lean animals. Expression of mRNA for these lipogenic enzymes was higher in obese animals and suggests that obese
mice may be resistant to polyunsaturated fatty acid feedback control of gene expression. 相似文献
20.
Isolation and characterization of the monounsaturated long chain fatty acids ofMycobacterium tuberculosis 总被引:2,自引:0,他引:2
The positions of double bond in the monounsaturated C15−C32 fatty acids ofMycobacterium tuberculosis H37Ra were established by gas chromatography/mass spectrometry of the ozonized esters and their pyrrolidide derivatives.
The monounsaturated C15−C21 fatty acids had the double bond primarily at the Δ9 position while the monounsaturated longer chain fatty acids (C22−C32) had the double bond in several positions. Many of the latter acids, especially the odd-numbered series, were very complex
isomeric mixtures. Quantitation showed the most abundant even-numbered long chain fatty acid isomers to be as follow: C22, Δ4; C24, Δ5; C26, Δ7 and Δ9; C28, Δ9; C30, Δ11 and Δ13; C32, Δ13 and Δ15. 相似文献