Separation Behavior of Octadecadienoic Acid Isomers and Identification of cis- and trans-Isomers Using Gas Chromatography

Lipids ◽  
2014 ◽  
Vol 50 (1) ◽  
pp. 85-100 ◽  
Author(s):  
Shigeaki Shibamoto ◽  
Andrew Gooley ◽  
Kouhei Yamamoto
1985 ◽  
Vol 68 (5) ◽  
pp. 911-916 ◽  
Author(s):  
Tadashi Doi ◽  
Shigeyuki Sakaue ◽  
Masao Horiba

Abstract The content of d-phenothrin in technical preparations was determined by gas chromatography (GC) on a column of 2% PEG-20M or 2% DEGS, using suitable internal standards. The cis- and trans-isomers were separated from each other and determined on a 2% QF-1 column. The 4 optical isomers of rf-phenothrin were hydrolyzed in alkaline conditions to liberate chrysanthemic acid, which was derivatized to diastereoisomeric </-2-octyl esters, and the isomer ratio was determined by GC. The 4 optical isomers were also separated from one another directly on a chiral Sumipax OA-2000 column by liquid chromatography (LC). Also, after the propellant gas in an aerosol formulation was released, and the remaining liquid was analyzed using the same GC conditions as those used for technical preparations


Weed Science ◽  
1975 ◽  
Vol 23 (1) ◽  
pp. 7-10 ◽  
Author(s):  
F. H. A. Rummens

The two isomers of diallate [S-2,3-dichloroallyl)diisopropylthiocarbamate] can be isolated by preparative scale gas chromatography using a Carbowax 20M liquid phase. on the basis of IR and NMR spectroscopic and other evidence the isomer with the shorter retention time is assigned the trans configuration and that with the longer retention time is assigned the cis configuration.


1964 ◽  
Vol 47 (5) ◽  
pp. 838-841
Author(s):  
Morton Beroza ◽  
Rafael Sarmiento

Abstract Means of analyzing trimedlure, medlure, siglure, butyl sorbate, cue-lure, and methyleugenol by gas chromatography have been devised to ensure the procurement of high quality attractants needed for the detection of insect pests, especially those invading noninfested areas. The methods permit the estimation of the 4 trans isomers present in commercially produced trimedlure and medlure, and of the cis and trans isomers of siglure. Commercially available butyl sorbate gives a single sharp peak and is supposed to be the trans, trans isomer. Cue-lure and methyleugenol each give a single peak.


Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4539
Author(s):  
Nguyen Minh Thuy ◽  
Vo Minh ◽  
Tran Ben ◽  
My Tuyen Thi Nguyen ◽  
Ho Ha ◽  
...  

Butterfly pea flower have great sensory attraction, but they have not yet been used widely in Vietnam. Extracts of butterfly pea flowers can be used conveniently as a natural blue colorant for food products. In this study, the identification of anthocyanin compounds in butterfly pea flowers was performed by UPLC coupled with a UV and Mass spectrometer instrument. Positive and negative ion electrospray MS/MS chromatograms and spectra of the anthocyanin compounds were determined. By analyzing the chromatograms and spectra for each ion, five anthocyanins were identified in the butterfly pea flower extract; these were delphinidin-3-(6”‐p-coumaroyl)-rutinoside, cyanidin 3-(6”-p-coumaroyl)-rutinoside, delphinidin-3-(p-coumaroyl) glucose in both cis- and trans- isomers, cyanidin-3-(p-coumaroyl-glucoside) and delphinidin-3-pyranoside. Additionally, based on their intensity, it was determined that cyanidin-3-(p-coumaroyl-glucoside) was the most abundant anthocyanin, followed by cyanidin 3-(6”-p-coumaroyl)-rutinoside, delphinidin-3-(p-coumaroyl-glucoside), delphinidin-3-(6”-p-coumaroyl)-rutinoside and delphinidin-3-pyranoside. In this study, cyanidin derivatives were discovered in butterfly pea flower extract, where these compounds had not been detected in previous studies.


2020 ◽  
Vol 153 (24) ◽  
pp. 244308
Author(s):  
Ali Abou Taka ◽  
Mark C. Babin ◽  
Xianghai Sheng ◽  
Jessalyn A. DeVine ◽  
Daniel M. Neumark ◽  
...  

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