THE SEPARATION OF SATURATED AND UNSATURATED FATTY ACID ESTERS BY GAS–LIQUID CHROMATOGRAPHY

1958 ◽  
Vol 36 (9) ◽  
pp. 1297-1301 ◽  
Author(s):  
B. M. Craig ◽  
N. L. Murty

Fatty acid methyl esters are separated according to chain length by using washed silicone grease supported on 20–40 mesh C22 firebrick. By using a plasticizer on the firebrick support the same esters are separated according to both chain length and degree of unsaturation. Together the two procedures can be used to determine the component fatty acids in fats and oils. Nearly parallel linear relations are obtained for saturated, monoethenoid, diethenoid, and triethenoid methyl esters when the logarithm of emergence time is plotted against the carbon number of the fatty acid.

Author(s):  
R E Pauls ◽  
B Pease

Abstract An ionic liquid (IL) 111 column was compared with other commonly employed stationary phases including polydimethyl siloxane and polyethylene glycol for the separation of fatty acid monomethyl and dimethyl esters. The fatty acid esters employed in this study were derived from metathesis reactions of vegetable oils both with and without olefins. The IL 111 column demonstrated enhanced performance compared with conventional columns for the separation of these esters. These advantages included significantly enhanced retention of dimethyl esters relative to monomethyl esters, excellent cis/trans isomer separation and the ability to analyze higher carbon number dimethyl esters. As a result, these columns are highly suited for the analysis of mixtures of mono- and dimethyl fatty acid esters found in lipid metathesis reaction products or to determine monofunctional impurities in samples of commercial dimethyl esters.


2016 ◽  
Vol 78 (5-6) ◽  
Author(s):  
Mohd Basyaruddin Abdul Rahman ◽  
Siti Salhah Othman ◽  
Noor Mona Md Yunus

The enzymatic selectivity of Lipase from Candida rugosa immobilized onto a calcined layered double hydroxide (CLDHs-CRL) towards the chain-length of fatty acids and alcohols in the synthesis of fatty acid esters was investigated.  The results showed that CMAN-CRL catalyzed the esterification process with fatty acids of medium chain lengths (C10-C14) effectively while, CNAN-CRL and CZAN-CRL exhibited high percentage conversion in fatty acids with carbon chain lengths of C8-C12 and C10-C18, respectively. In the alcohol selectivity study, CMAN-CRL showed high selectivity toward alcohols with carbon chain lengths of C4, C6 and C10.  On the other hand, both CNAN-CRL and CZAN-CRL exhibited rather low selectivity towards longer carbon chain length of alcohols. 


Cosmetics ◽  
2019 ◽  
Vol 6 (3) ◽  
pp. 45 ◽  
Author(s):  
Dorota Dobler ◽  
Thomas Schmidts ◽  
Sören Wildenhain ◽  
Ilona Seewald ◽  
Michael Merzhäuser ◽  
...  

Human skin is a complex ecosystem and is host to a large number of microorganisms. When the bacterial ecosystem is balanced and differentiated, skin remains healthy. However, the use of cosmetics can change this balance and promote the appearance of skin diseases. The skin’s microorganisms can utilize some cosmetic components, which either promote their growth, or produce metabolites that influence the skin environment. In this study, we tested the ability of the Malassezia species and some bacterial strains to assimilate substances frequently used in dermal formulations. The growth capability of microorganisms was determined and their lipase activity was analyzed. The growth of all Malassezia spp. in the presence of free acids, free acid esters, and fatty alcohols with a fatty chain length above 12 carbon atoms was observed. No growth was observed in the presence of fatty alcohol ethers, secondary fatty alcohols, paraffin- and silicon-based substances, polymers, polyethylene glycols, quaternary ammonium salts, hydroxy fatty acid esters, or fatty acids and fatty acid esters with a fatty chain length shorter than 12 carbon atoms. The hydrolysis of esters by Malassezia lipases was detected using High Performance Thin Layer Chromatography (HPTLC). The production of free fatty acids as well as fatty alcohols was observed. The growth promotion or inhibition of bacterial strains was only found in the presence of a few ingredients. Based on these results, formulations containing microbiome inert ingredients were developed.


1962 ◽  
Vol 40 (6) ◽  
pp. 1118-1122 ◽  
Author(s):  
N. Narasimhachari ◽  
E. Von Rudloff

The wood of the showy mountain ash was found to contain about 3% acetone-soluble material. The major constituents of the extract were a polymorphous xyloside of (+)-di-methoxyisolariciresinol, the recently discovered hydroxy diphenyls aucuparin and methoxyaucuparin, and fatty acid esters of β-sitosterol, another phytosterol, and of untractable phenolic material. Small amounts of free β-sitosterol and a mixture of hydrocarbons as well as traces of an unknown leucoanthocyanidin were also isolated. The xyloside predominated in the sapwood, whereas the aucuparins were found mainly in the heartwood. Gas–liquid chromatography was instrumental in the detection and separation of the aucuparins.


2010 ◽  
Vol 112 (2) ◽  
pp. 158-165 ◽  
Author(s):  
Rüdiger Weißhaar ◽  
Roland Perz

1996 ◽  
Vol 43 (4) ◽  
pp. 707-711 ◽  
Author(s):  
V Kulcitsky ◽  
J Hertel ◽  
E Skoczylas ◽  
E Swiezewska ◽  
T Chojnacki

The presence of poly-cis-prenols of chain length 20-60 isoprene units or longer in leaves of plants belonging to Combretaceae family was shown to be a common feature in this group of plants. The polyprenols of this type were found in half of the 20 species studied. In most cases the polyprenols occurred in the form of fatty acid esters. Only in one species--Combretum molle, the polyprenols were found in the form of free alcohols. The amount of long-chain polyprenols varied with the plant species; the richest source was C. molle (about 4% of dry mass of leaves). Polyprenol groups characteristic of other systematic families of plants were not found in the Combretaceae studied.


1983 ◽  
Vol 66 (4) ◽  
pp. 1050-1052
Author(s):  
Taizo Tsuda ◽  
Hiroshi Nakanishi

Abstract A method was developed for gas-liquid chromatographic determination of sucrose fatty acid esters as TMS derivative of sucrose and methyl esters of fatty acids. Sucrose fatty acid esters were completely degraded to sucrose and fatty acids in alkaline ethanol overnight at 25°C. Sucrose was derivatized with pyridine, trimethylchlorosilane, and N-trimethylsilylimidazole and the sucrose TMS derivative was determined on a 2% OV-17 column. Fatty acids were extracted with ethyl ether, methylated with BF3-methanol complex at 65°C, and determined on a 2% DEGS + 0.5% H3PO4 column. This method was applied to selected sucrose fatty acid esters. For example, sucrose and fatty acids derived from 50 mg sample F20 were 10.6-11.0 and 38.1-39.0 mg, respectively. Total amounts were 48.7-50.0 mg with a standard deviation of 0.4 (n = 6).


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