A 1H NMR study of the fatty acid distribution in developing flax bolls before and after a cooking treatment

2011 ◽  
Vol 89 (9) ◽  
pp. 1138-1142 ◽  
Author(s):  
Christopher W. Kirby ◽  
Jason L. McCallum ◽  
Bourlaye Fofana
Keyword(s):  
Edible Oils ◽  
Fatty Acid Distribution ◽  
H Nmr ◽  
Early Stages ◽  
Nmr Study ◽  
Cooking Process ◽  
Ester Formation ◽  
Before And After ◽  
Flax Cultivar ◽  
Seed Crops

Flax is an important Canadian crop that contains a large percentage of fatty acids (FAs) by seed weight. Gas chromatography (GC) methods have traditionally been used to study FA distributions in oil seed crops. These methods, however, require sample preparation involving saponification and methyl ester formation. Recently, 1H NMR has been shown to be an excellent way to directly measure FA distributions in edible oils using a nondestructive and experimentally faster methodology. As such, we have examined the FA profiles in developing bolls of flax cultivar AC McDuff using 1H NMR and assessed the effect of cooking on FA stability and distribution. The data confirmed the high percentage of linolenic acid in mature AC McDuff flax seed compared to early stages of development and showed that FAs at early stages of boll development are more prone to thermal degradation. Triacylglycerol was found to be important to FA stability to heat. It was also observed that the FAs did not convert from cis to trans under the cooking process used herein. The usefulness of 1H NMR spectroscopy in oils chemistry is highlighted.

A 15N, 13C, and 1H NMR study of reaction products from arylguanidines and chloroformate esters

1991 ◽  
Vol 56 (7) ◽  
pp. 1505-1511 ◽  
Author(s):  
Antonín Lyčka ◽  
Karel Palát
Keyword(s):  
1H Nmr ◽  
Nmr Spectra ◽  
Reaction Products ◽  
H Nmr ◽  
Nmr Study

The 15N, 13C, and 1H NMR spectra of the reaction products from arylguanidines with two mols of chloroformate esters have been measured. With application of the corresponding 15N isotopomer it has been proved that the reaction products have the structures IIIa-IIIc.

scholarly journals Tautomerisation in 1-(4-Methylphenylazo)naphthalen-2-ol and 2-(4-Methylphenylazo)-4-methylphenol: A Crystallographic and 13C{1H}NMR Study

1999 ◽  
Vol 23 (3) ◽  
pp. 178-179
Author(s):  
Wendy I. Cross ◽  
Kevin R. Flower ◽  
Robin G. Pritchard
Keyword(s):  
Acetic Acid ◽  
Nmr Spectroscopy ◽  
Resonant Frequency ◽  
X Ray Diffraction ◽  
X Ray ◽  
H Nmr ◽  
Nmr Study ◽  
Acetic Acid Esters ◽  
Acid Esters ◽  
Equivalent Carbon

The acetic acid esters of 1-(4-methylphenylazo)naphthalen-2-ol 1 and 2-(4-methylphenylazo)-4-methylphenol 3 are prepared and characterised by single crystal X-ray diffraction studies and 13C{1H}NMR spectroscopy; the position of the C(2)13C resonance for the ester is used to predict the position of resonant frequency of the equivalent carbon in the parent alcohols and hence, calculate the position of the azo-hydrazone equilibrium in these compounds.

scholarly journals Hepatic lipid signatures of little brown bats (Myotis lucifugus) and big brown bats (Eptesicus fuscus) at early stages of white-nose syndrome

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Evan L. Pannkuk ◽  
Nicole A. S.-Y. Dorville ◽  
Yvonne A. Dzal ◽  
Quinn E. Fletcher ◽  
Kaleigh J. O. Norquay ◽  
...  
Keyword(s):  
Lipid Metabolism ◽  
Fatty Acid Distribution ◽  
Eptesicus Fuscus ◽  
Myotis Lucifugus ◽  
Pseudogymnoascus Destructans ◽  
Hepatic Lipid ◽  
Early Stages ◽  
White Nose Syndrome ◽  
Big Brown Bats ◽  
Little Brown Bats

AbstractWhite-nose syndrome (WNS) is an emergent wildlife fungal disease of cave-dwelling, hibernating bats that has led to unprecedented mortalities throughout North America. A primary factor in WNS-associated bat mortality includes increased arousals from torpor and premature fat depletion during winter months. Details of species and sex-specific changes in lipid metabolism during WNS are poorly understood and may play an important role in the pathophysiology of the disease. Given the likely role of fat metabolism in WNS and the fact that the liver plays a crucial role in fatty acid distribution and lipid storage, we assessed hepatic lipid signatures of little brown bats (Myotis lucifugus) and big brown bats (Eptesicus fuscus) at an early stage of infection with the etiological agent, Pseudogymnoascus destructans (Pd). Differences in lipid profiles were detected at the species and sex level in the sham-inoculated treatment, most strikingly in higher hepatic triacylglyceride (TG) levels in E. fuscus females compared to males. Interestingly, several dominant TGs (storage lipids) decreased dramatically after Pd infection in both female M. lucifugus and E. fuscus. Increases in hepatic glycerophospholipid (structural lipid) levels were only observed in M. lucifugus, including two phosphatidylcholines (PC [32:1], PC [42:6]) and one phosphatidylglycerol (PG [34:1]). These results suggest that even at early stages of WNS, changes in hepatic lipid mobilization may occur and be species and sex specific. As pre-hibernation lipid reserves may aid in bat persistence and survival during WNS, these early perturbations to lipid metabolism could have important implications for management responses that aid in pre-hibernation fat storage.

Mobility and relaxation of amorphous chains in drawn polypropylene: 2 H-NMR study

Polymer ◽  
1999 ◽  
Vol 40 (18) ◽  
pp. 5227-5232 ◽  
Author(s):  
M. Botev ◽  
R. Neffati ◽  
J. Rault
Keyword(s):  
H Nmr ◽  
Nmr Study

scholarly journals NMR-Spectrometric Determination of the Fragmented Oil Composition from the Karazhanbas and Zhangurshi Oil Deposits

2018 ◽  
Vol 20 (3) ◽  
pp. 229
Author(s):  
D.U. Bodykov ◽  
T.M. Seilkhanov ◽  
M. Nazhipkyzy ◽  
A.S. Toylybayev ◽  
R. Salakhov
Keyword(s):  
13C Nmr ◽  
13C Nmr Spectroscopy ◽  
High Viscosity ◽  
Oil Composition ◽  
Alkyl Chains ◽  
H Nmr ◽  
A Value ◽  
Heavy Oil Residues ◽  
Before And After ◽  
Integrated Intensities

The methods of 1 H, 13C NMR-spectroscopy were used to study the fragmentary compositions of oil from the Karazhanbas, Zhangurshi deposits (Kazakhstan) and heavy oil residues obtained before and after the electrohydraulic effect of water hammer after topping a light fraction of oil products. Their fragmentary composition were determined by the value of integrated intensities of 1 H, 13C NMR signals of the oil under study. The obtained results have shown that the composition of oil samples understudy includes terminal CH3-groups of long alkyl chains having a value of 0.87 ppm. The presence of long alkyl chains of oil components imparts a high viscosity and bituminous consistency to the latter. The content of aromatic protons according to the integrated intensities of 1 H NMR in both oil samples does not exceed 2.08%; but there are no aromatic nuclei by the integral intensities of carbon atoms at all. The low content of protons of Hα-type in hydrocarbon crude (5.2–5.3%) indicates a low content of aromatic and carbonyl carbons as well as heteroatoms in the studied samples. The content of the greater proportion of protons of the Hγ-type in Karazhanbas oil (33.0%) compared to the Zhangurshi oil (23.8%) indicates a greater length of aliphatic hydrocarbons of the latter and its increased viscosity.

Sign in / Sign up

Export Citation Format

Share Document