Equivalent chain-lengths of methyl ester derivatives of fatty acids on gas chromatography A reappraisal

1988 ◽  
Vol 447 ◽  
pp. 305-314 ◽  
Author(s):  
W.W. Christie
Keyword(s):  
Fatty Acids ◽  
Gas Chromatography ◽  
Methyl Ester ◽  
Chain Lengths ◽  
Derivatives Of

Distinguishing Between One-Day-Old Cod (Gadus morhua) and Haddock (Melanogrammus aeglefinus) Eggs by Gas Chromatography and SIMCA Pattern Recognition

1985 ◽  
Vol 42 (11) ◽  
pp. 1823-1826 ◽  
Author(s):  
H. Knutsen ◽  
E. Moksnes ◽  
N. B. Vogt
Keyword(s):  
Fatty Acids ◽  
Pattern Recognition ◽  
Gas Chromatography ◽  
Multivariate Analysis ◽  
Methyl Ester ◽  
Gadus Morhua ◽  
Melanogrammus Aeglefinus ◽  
One Step ◽  
High Resolution Gas Chromatography ◽  
Haddock Melanogrammus Aeglefinus

Single cod (Gadus morhua) and haddock (Melanogrammus aeglefinus) eggs were acid hydrolized. All the fatty acids were liberated and converted to methyl ester in a one-step reaction. The nonpolar hexane extract was analyzed by high resolution gas chromatography (HRGC). Selected peaks, occurring in both types of samples and in all chromatograms, were used to create a matrix for multivariate analysis. We conclude that cod and haddock eggs can be distinguished using this method.

scholarly journals Authentication of Wistar rat fats with gas chromatography mass spectometry combined by chemometrics

10.5219/1229 ◽  
2020 ◽  
Vol 14 ◽  
pp. 52-57
Author(s):  
Any Guntarti ◽  
Ibnu Gholib Gandjar ◽  
Nadia Miftahul Jannah
Keyword(s):  
Fatty Acids ◽  
Gas Chromatography ◽  
Methyl Ester ◽  
Unsaturated Fatty Acids ◽  
Saturated Fatty Acids ◽  
Principal Component ◽  
Total Content ◽  
Wistar Rat ◽  
Animal Fats ◽  
Mass Spectometry

Indonesia is a country with the largest Muslim population in the world, which is very concerned about halal food. The most problem that’s very concerning nowadays was that food products were contaminated by unclean meat, such as rat meat. The purpose of this study was to authenticate rat fat using Gas Chromatography-Mass Spectrophotometry (GC-MS) combined with chemometrics. In this study, rat fat were heated in oven at 90 °C – 100 °C for approximately one hour until the oil came out. After that, the derivatization process was carried out to convert fat into methyl ester compounds using NaOCH3 and BF3. Methyl ester compound than injected into the GCMS instrument system. In addition to rat fat, other fat extraction were carried out, such as pigs, cows, chickens, wild boars, dogs, and goats. The combination of chemometrics Principal Component Analysis (PCA) was used to classify rat fat with other animal fat. Based on the results of the study showed that fatty acids in rats using GCMS produced 6 types of fatty acids, namely: myristat (0.15 ±0.09%), palmitoleate (0.73 ±0.54%), palmitate (19.08 ±3.54%), linoleate (30.14 ±16.90%), oleate (40.48 ±2.74%), and stearate (2.55 ±0.01%). Total content of rat fatty acids was 93.13%, with unsaturated fatty acids 71.35% and saturated fatty acids 21.78%. Chemometrics PCA from rat fat can be grouped with other animal fats

Identification of the unsaturated oxo fatty acids in cheese

1994 ◽  
Vol 61 (1) ◽  
pp. 111-115 ◽  
Author(s):  
Elizabeth Y. Brechany ◽  
William W. Christie
Keyword(s):  
Mass Spectrometry ◽  
Fatty Acids ◽  
Gas Chromatography ◽  
Column Chromatography ◽  
Cheddar Cheese ◽  
Silver Ion ◽  
Picolinyl Ester ◽  
Gas Chromatography Mass Spectrometry ◽  
Double Bonds ◽  
Chain Lengths

SummaryThe nature and composition of the unsaturated (monoenoic) oxo fatty acids in Cheddar cheese have been re-evaluated. Following isolation by column chromatography and silver ion HPLC, the fatty acids were identified in the form of their picolinyl ester derivatives by gas chromatography–mass spectrometry. For confirmation, they were analysed similarly following deuteration of the double bonds with deuterium and Wilkinson's catalyst. Fifteen fatty acids were identified fully, only five of which corresponded to those reported in an earlier study. Isomers with double bonds in positions 5, 7, 9 and 11–15 were identified, with oxo groups in positions 8, 9, 10, 13, 16 and 17, and with chain-lengths varying from C14 to C18, but with C18 predominating.

Identification of the saturated oxo fatty acids in cheese

1992 ◽  
Vol 59 (1) ◽  
pp. 57-64 ◽  
Author(s):  
Elizabeth Y. Brechany ◽  
William W. Christie
Keyword(s):  
Mass Spectrometry ◽  
Fatty Acids ◽  
Gas Chromatography ◽  
Methyl Ester ◽  
Chain Length ◽  
Column Chromatography ◽  
Silver Ion ◽  
Picolinyl Ester ◽  
Gas Chromatography Mass Spectrometry ◽  
First Time

SummaryThe nature and composition of the saturated oxo fatty acids in Cheddar cheese have been re-evaluated following isolation by moern chromatographic procedures, including low-pressure column chromatography and HPLC (adsorption and silver ion modes). The oxo fatty acids were identified and quantified (for the first time) by gas chromatography–mass spectrometry in the form of the methyl ester derivatives and many of the structures were confirmed similarly by preparing picolinyl ester derivatives. Thirty-six saturated oxo fatty acids were identified, ranging in chain length from 9 to 22 with an oxo group on carbons 4–17 (except for 12), of which twenty-one had been identified in a previous study and fifteen were new. Fifteen fatty acids tentatively identified by others did not in fact appear to be present.

scholarly journals Anaerobic n-Alkane Metabolism by a Sulfate-Reducing Bacterium, Desulfatibacillum aliphaticivorans Strain CV2803T

2005 ◽  
Vol 71 (7) ◽  
pp. 3458-3467 ◽  
Author(s):  
Cristiana Cravo-Laureau ◽  
Vincent Grossi ◽  
Danielle Raphel ◽  
Robert Matheron ◽  
Agnès Hirschler-Réa
Keyword(s):  
Mass Spectrometry ◽  
Fatty Acids ◽  
Gas Chromatography ◽  
Chain Elongation ◽  
Gas Chromatography Mass Spectrometry ◽  
Sulfate Reducing ◽  
Cellular Fatty Acids ◽  
Branched Fatty Acids ◽  
Chain Lengths ◽  
Methyl Branched Fatty Acids

ABSTRACT The alkane-degrading, sulfate-reducing bacterium Desulfatibacillum aliphaticivorans strain CV2803T, recently isolated from marine sediments, was investigated for n-alkane metabolism. The total cellular fatty acids of this strain had predominantly odd numbers of carbon atoms (C odd) when the strain was grown on a C-odd alkane (pentadecane) and even numbers of carbon atoms (C even) when it was grown on a C-even alkane (hexadecane). Detailed analyses of those fatty acids by gas chromatography/mass spectrometry allowed us to identify saturated 2-, 4-, 6-, and 8-methyl- and monounsaturated 6-methyl-branched fatty acids, with chain lengths that specifically correlated with those of the alkane. Growth of D. aliphaticivorans on perdeuterated hexadecane demonstrated that those methyl-branched fatty acids were directly derived from the substrate. In addition, cultures on pentadecane and hexadecane produced (1-methyltetradecyl)succinate and (1-methylpentadecyl)succinate, respectively. These results indicate that D. aliphaticivorans strain CV2803T oxidizes n-alkanes into fatty acids anaerobically, via the addition of fumarate at C-2. Based on our observations and on literature data, a pathway for anaerobic n-alkane metabolism by D. aliphaticivorans is proposed. This involves the transformation of the initial alkylsuccinate into a 4-methyl-branched fatty acid which, in addition to catabolic reactions, can alternatively undergo chain elongation and desaturation to form storage fatty acids.

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