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1.
Limanathes douglasii seed oil glycerides contain fatty acids which predominantly (97%) have 20 or more carbon atoms. Fatty acids were prepared by saponification; fatty alcohols, by sodium reduction of the glycerides; and liquid wax esters, byp-toluenesulfonic acid-catalyzed reaction of the fatty acids with the fatty alcohols. Solid waxes were prepared by hydrogenation of the glyceride oil and of the wax esters. Chemical and physical constants were determined forLimnanthes douglasii seed oil and its derivatives. The liquid wax esters had properties very similar to those of jojoba (Simmondsia chinensis) seed oil. The solid hydrogenated wax ester was identical in physical appearance and melting point to hydrogenated jojoba seed oil. A laboratory of the Northern Utilization Research and Development Division, Agricultural Research Service, USDA.  相似文献   

2.
Crambe abyssinica andLunaria annua, members of the Cruciferae family, have seed oil glycerides containing ca. 55–65% of C22 and C24 unsaturated fatty acids. Fatty acids were prepared by saponification; fatty alcohols, by sodium reduction of glycerides; liquid wax esters, byp-toluenesulfonic acid-catalyzed reaction of fatty acids with fatty alcohols; and methyl esters, by reaction of fatty acids with diazomethane. Solid hydrogenated glyceride oils and wax esters were compared with several commercial waxes. Chemical and physical constants were determined for the seed oils and their derivatives. Position of unsaturation in theCrambe fatty acids was determined by gas chromatographic analysis of the permanganate-periodate degradation products. The major dicarboxylic acid was brassylic (C13), proving the docosenoic acid to be erucic. Presented in part at the AOCS meeting in New Orleans, La., 1962. A laboratory of the No. Utiliz. Res. & Dev. Div., ARS, U.S.D.A.  相似文献   

3.
Summary Jojoba oil is a liquid wax composed essentially of C20 and C22 straight-chain monoethylenic acids and alcohols in the form of esters. Sodium reduction of the wax fatty esters in jojoba oil yielded quantitatively a mixture of unsaturated, long-chain alcohols from the acid moiety of the jojoba oil. Yields of about 91% were obtained in the laboratory-scale experiments and 82 to 86 for the pilot-plant experiments. Analytical data, including detailed infrared spectra information, are given for the resulting product alcohols. Presented at the fall meeting, American Oil Chemists' Society, Cincinnati, O., September 29-October 2, 1957. One of the laboratories of the Southern Utilization Research and Development Division, Agricultural Research Service, U. S. Department of Agriculture.  相似文献   

4.
A method for the routine determination of jojoba wax ester composition and the ethanolysis products of these esters is described. In the recommended procedure, single or half seeds are crushed onto filter paper disks to provide duplicate 10–20 mg samples of the wax. One paper is extracted with petroleum ether for wax ester analysis and the second sample is transesterified in a sealed bottle using 5% HCl in ethanol at 80 C for 1–2 hr. This preparation is extracted with NaCl and petroleum ether, neutralized with potassium bicarbonate and dried with anhydrous sodium sulfate. The fatty acid ethyl esters and free alcohols are determined by gas chromatography (GC). The method requires only small amounts of seed material, provides duplicate samples of the wax, simplifies the ethanolysis procedures and reduces the time needed for the removal of the acid catalyst.  相似文献   

5.
The alkyl esters of beeswax, after isolation from the unhydrolyzed wax by preparative layer chromatography (PLC), have been analyzed directly by high temperature GLC using 1.5% OV1 as liquid phase. In two commercial wax samples examined the ester homologues are predominantly even carbon numbered ranging from C36 to C54. The principal alkyl esters are C40, C42, C44, C46 and C48. The GLC analysis of the ester hydrolysis products revealed that the variations in ester chain length are produced by variations in the esterified primary alcohol chain lengths. The esterified fatty acid is chiefly hexadecanoic acid. The esterified fatty acids differ in composition from the free fatty acids which are also present in the wax.  相似文献   

6.
The predominating molecular species in jojoba oil iscis-13-docosenylcis-11-eicosenoate (erucyl jojobenoate), ranging from 31% to 45% of the extracted seed oil. Other alcohol/acid combinations contribute to the C42 molecular chain length so that this fraction constitutes a low of 41% to a high of 57% of the total wax esters. The positions of the exclusivelycis ethylenic bonds in the alcohol and acid moieties of the wax esters are 99% ω-9 and 1% ω-7. Only 2% of the alcohol and acid moieties were saturated when analyzed after saponification of the oil. Triglycerides were detected by gas chromatography in all of the more than 200 natural jojoba oil samples tested, a few of which had substantially more than the normal 1%. Among the many uses of jojoba oil cited here, the two most promising are the sulfurized oil as extreme-pressure/extreme-temperature lubricant additive and the natural or refined oil formulated into cosmetic products.  相似文献   

7.
Separation of sterol esters from wax esters in the lipids of vernix caseosa and adult human skin surface was accomplished by column chromatography on MgO. The fatty acids of the sterol esters and wax esters of both samples were separated into saturates and monoenes, and examined in detail by gas liquid chromatography (GLC). The saturated fatty acids of the wax esters of vernix caseosa and of adult human skin surface were remarkably similar. They ranged in chain length from at least C11 to C30, six skeletal types being present: straight even, straight odd, iso, anteiso, other monomethyl branched and dimethyl branched. A large number of patterns of monoenes were observed, each pattern consisting of desaturation of a specific chain at Δ6 or Δ9 plus its extension or degradation products. The mole per cent of the total Δ6 and Δ9 patterns of wax ester fatty acid monoenes of vernix caseosa were 87% and 12%, respectively, and 98% and 1%, respectively, for adult human skin surface lipid. The sterol ester fatty acids of vernix caseosa were much different from those of adult human skin surface: vernix caseosa saturates were largely branched and of lengths greater than C18, whereas the saturates of adult human surface lipid resembled the wax ester fatty acids. Of the vernix caseosa monoene patterns, the mole per cent was 30% Δ6 and 70% Δ9, whereas of the adult human skin surface sterol ester fatty acids 89% were Δ6 and 11% Δ9. Chain extension was particularly pronounced in the sterol ester fatty acid monoenes of vernix caseosa amounting to 7–8 C2 units in some cases. The fatty acids of the sterol esters of both vernix caseosa and adult human skin surface appear to be derived from the sebaceous gland and from the keratinizing epidermis, but those of the wax esters are from the sebaceous glands only.  相似文献   

8.
A rapid ethanolysis procedure for preparing jojoba wax for gas liquid chromatographic analysis is described. The wax esters are hydrolyzed by refluxing 4 drops of jojoba wax in 5% HCl in anhydrous ethanol in a test tube. The resulting fatty acid ethyl esters and fatty alcohols are separated and quantitated by a single gas liquid chromatographic run. Analysis of duplicate samples by this procedure gives essentially the same results as a procedure which requires 10 times more sample and reagents and considerably more time.  相似文献   

9.
Chemical structure of long-chain esters from “sansa” olive oil   总被引:1,自引:0,他引:1  
The major objective of this study was to determine the chemical structure of long-chain esters present in lower-grade olive oil. The classes of esters composing the hexanediethyl ether (99∶1) extract of the wax fraction from a pomace olive oil were: (i) esters of oleic acid with C1−C6 alcohols, (ii) esters of oleic acid with long-chain aliphatic alcohols in the range C22−C28 and (iii) benzyl alcohol esters of the very long-chain saturated fatty acids C26 and C28. The analysis and the structure assignments were carried out by gas chromatography coupled with mass spectrometry and by comparison with synthetic authentic model compounds. This work provided precise data on the chemical nature of the wax esters present in olive oil and should represent a means to detect adulteration of higher-grade olive oil with less expensive pomace olive oil and seed oils.  相似文献   

10.
Grain sorghum wax has been judged to be a potential source of natural wax with properties similar to carnauba wax. Approximately 0.16–0.3% (w/w) wax can be extracted from grain sorghum depending on the efficiency of the organic solvents. Although the melting points of carnauba wax and sorghum wax are similar, i.e., 78–86 and 77–85°C, respectively, they differ in acid values, i.e., 2–10 and 10–16, respectively, and saponification numbers, i.e., 77–95 and 16–49, respectively. Improved knowledge of the properties, composition, and analysis of grain sorghum wax would assist in efforts for industrial application of this product. Major components of sorghum wax are hydrocarbons, wax esters, aldehydes, free fatty alcohols, and FFA. The hydrocarbons consist mainly of C27 and C29, and the aldehydes, alcohols, and acids are mainly C28 and C30. The wax esters are mostly esters of C28 and C30 alcohols and acids.  相似文献   

11.
Wax composition of sunflower seed oils   总被引:1,自引:3,他引:1  
Waxes are natural components of sunflower oils, consisting mainly of esters of FA with fatty alcohols, that are partially removed in the winterization process during oil refining. The wax composition of sunflower seed as well as the influence of processing on the oil wax concentration was studied using capillary GLC. Sunflower oils obtained by solvent extraction from whole seed, dehulled seed, and seed hulls were analyzed and compared with commercial crude and refined oils. The main components of crude sunflower oil waxes were esters having carbon atom numbers between 36 and 48, with a high concentration in the C40−C42 fraction. Extracted oils showed higher concentrations of waxes than those obtained by pressing, especially in the higher M.W. fraction, but the wax content was not affected significantly by water degumming. The hull contribution to the sunflower oil wax content was higher than 40 wt%, resulting in 75 wt % in the crystallized fraction. The oil wax content could be reduced appreciably by hexane washing or partial dehulling of the seed. Waxes in dewaxed and refined sunflower oils were mainly constituted by esters containing fewer than 42 carbon atoms, indicating that these were mostly soluble and remained in the oil after processing.  相似文献   

12.
Lipids were extracted from the mandibular fat body (jaw), the fatty forehead (melon), and the dorsal blubber of a Pacific beaked whale (Berardius bairdi) and separated into lipid classes by preparative thin layer chromatography. The head fats were mixtures of wax esters and triglycerides with a very small amount of diacyl glyceryl ether. The blubber fat contained 97% was ester and 3% triglyceride. Gas liquid chromatography (GLC) of the intact lipid classes indicated an unusually low C26–C30 range for most of the jaw and melon wax esters compared to the more normal C32–C40 molecules found in the blubber. Distinctive lower molecular weight C24–C40 triglycerides occurred in the head fats vs. the usual C44–C58 range in the blubber. Most diacyl glyceryl ethers were in the C35–C46 range, below the molecular weight of hexadecyldipalmitoyl glyceryl ether (C48). GLC of the derived fatty acid methyl esters showed that the lower molecular weight neutral lipids in the head fats were due to high levels of iso-10∶0, n−10∶0, iso-11∶0, iso-12∶0, n−12∶0, and iso-13∶0 acids. The wax ester fatty alcohols and the alkoxy chains of the glyceryl ethers were mostly the C14–C20 chain lengths commonly observed in marine organisms. The distinctive medium chain neutral lipids in the jaw and melon fats of this whale may be related to the postulated acoustical role of these tissues in echolocation.  相似文献   

13.
A lack of reliability in the usual determinations of fatty acids and fatty alcohols of jojoba wax prompted us to propose an original method of hydrolysis and extraction, making it possible to better determine the composition of fatty acids and alcohols of the wax. High-performance liquid chromatography fractionation of the wax allowed isolation of four main classes of esters (which differed by their partition number). The detailed study of these ester classes emphasized the way acids and alcohols are connected, and fourteen distinct esters were thus identified. Some triacylglycerols, free fatty alcohols and other minor components of jojoba wax were found and quantitated. Seven sterols were identified, four for the first time.  相似文献   

14.
The lipid fraction of the deep water fish species orange roughy (Hoplostetbus atlanticus), black oreo (Allocyttus sp.) and small spined oreo (Pseudocyttus maculatus) had wax esters with even carbon numbers over the range C30 to C46 as the major components. The component acids and alcohols of the wax ester fraction were analyzed by gas liquid chromatography and compared with those of jojoba and sperm whale oils. Orange roughy oil was refined and deodorized and its chemical, physical and mechanical properties were determined. Hydrogenation of orange roughy oil produced a range of white crystalline waxes with melting points between 34 and 66 C. The characteristics of these waxes were very similar to those of hydrogenated jojoba oil and spermaceti. Lubricant tests performed on sulfurized orange roughy oil indicated it is comparable to sulfurized jojoba and sperm whale oils as an extreme-pressure additive in lubricants. The results show a sound technical basis on which to consider an industry based on orange roughy oil and the oreo oils as replacements for sperm whale oil and as substitutes for jojoba oil. Applications for the oil could be in the cosmetic and high-grade lubricant fields, the waxes in the polish, textile, cosmetic and pharmaceutical industries and the sulfurized derivative of orange roughy oil in the lubricant industry.  相似文献   

15.
Euglena gracias (ATCC 12716) grown on yeast-malt extract medium synthesized wax esters. Saturated even-numbered acids and alcohols (C12 to C18) were major con-stituents, with traces of odd-numbered fatty acids and alcohols. Tetradecanoic acid and tetradecanyl alcohol were the predominant components, and tetradecanyl tetradecanoate was the predominant wax ester. 1Part of a presentation at the American Oil Chemists’ Society Annual Meeting in May 1988 in Phoenix, AZ.  相似文献   

16.
The lower jaw fat of the Amazon River dolphinInia geoffrensis contains 52.8% wax ester, 44.7% triglyceride and 2.5% diacyl glyceryl ether, while its dorsal blubber fat is >98% triglyceride. Examination of the intact lipids, the derived fatty acids and the derived fatty alcohols by gas chromatography reveals that the blubber triglycerides show characteristics of freshwater fish fats, but the jaw fat lipids have several distinctive features. Jaw fat wax esters, triglycerides and diacyl glyceryl ethers are all rich in C10, C12 and C14 fatty acids and contain no polyunsaturated acids. The fatty alcohols in the wax esters are over 90% saturated. The major carbon numbers in the jaw fat triglycerides (C38–C46) are considerably lower than those of the blubber triglycerides (C48–C54). The possible adaptation of the jaw lipids for use in the underwater echolocation process of this dolphin is discussed.  相似文献   

17.
Thin layer chromatography and infrared spectophotometry of the fat of Eriobotrya japonica shows the presence of hydrocarbons (3.1%), was esters (5.3%), triglycerides (786%) and the last polar fraction containing fatty acids, colouring matter etc. (13.0%). After the saponification of the fat, the fatty acids C12-C24 and fatty alcohols C12-C26 determined first time as methyl esters and acetates respectively were identified by the application of gas liquid chromatography.  相似文献   

18.
Sulfonated acrylate esters have been synthesized by using renewable raw materials such as fatty alcohols of Al‐Ceder oil. Mixed fatty acids were isolated from Al‐Ceder oil by hydrolysis; both saturated and unsaturated fatty acids were isolated from the mixed fatty acids. The methyl esters of mixed fatty acid, saturated and unsaturated acids of Al‐Cedre oil were subjected to reduction with (LiAlH4) to give the corresponding fatty alcohols. The products of the reduction process were saponified and the hydroxyl values were estimated to further confirm the reduction occurrence. The acrylate esters were synthesized by esterification of acrylic acid with fatty alcohols of C16:0, C18:0, C18:1, and C18:2 mixed saturated, mixed unsaturated and mixed fatty acids of Al‐Cedre oil, respectively. This esterification was followed by addition of NaHSO3 to form bisulfite adducts. The structures of the prepared surfactants were characterized by IR and 1HNMR spectroscopy. A series of useful surface parameters, stability towards acids and base hydrolysis and calcium stability have been determined.  相似文献   

19.
The physicochemical and fatty acid compositions of seed oil extracted from Thunbergia fragrans were determined. The oil content, free fatty acids, peroxide value, saponification value and iodine value were 21.70 %, 2.25 % (as oleic acid), 9.6 (mequiv. O2/kg), 191.71 (mg KOH/g) and 127.84 (g/100 g oil) respectively. The fatty acid profiles of the methyl esters showed the presence of 90.16 % unsaturated fatty acids and 9.84 % saturated fatty acids. Palmitoleic acid, which is usually found in marine foods and is unique in seed oils of botanical origin, was the major component (79.24 %). The oil can also be used in industries for the preparation of liquid soaps, shampoos and alkyd resin.  相似文献   

20.
Triglyceride compounds isolated from jojoba seed oil by column chromatography were composed predominantly of C18′ C20′ C22′ and C24 n−9 fatty acids with minor amounts of saturated C16. Chain length and double-bond positions were determined by gas-liquid chromatography and gas-liquid chromatography-mass spectrometry of the corresponding methyl ester and picolinyl ester derivatives. Triglyceride structures were analyzed directly by ion trap mass spectrometry. The analysis of minor compounds, can provide highly specific information about the identity of an oil.  相似文献   

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