Detection of Chick Edema Factor in Fats and Fatty Acids by Electron Capture Gas Chromatography

1967 ◽  
Vol 50 (4) ◽  
pp. 874-879
Author(s):  
G R Higginbotham ◽  
David Firestone ◽  
Linda Chavez ◽  
A D Campbell
Keyword(s):  
Fatty Acids ◽  
Gas Chromatography ◽  
Electron Capture ◽  
Screening Test ◽  
Alumina Column ◽  
The Third ◽  
Edema Factor ◽  
Collaborative Studies ◽  
Alumina Column Chromatography ◽  
Chromatographic Peaks

Abstract An electron capture gas chromatographic screening test has been developed for detecting chick edema factor in fats and fatty acids. The procedure involves extraction of unsaponifiables from 10 g fat, alumina column chromatography of the unsaponifiables, sulfuric acid cleanup of the third alumina fraction (25% ethyl ether in petroleum ether), and electron capture gas chromatography at 200°C. Gas chromatographic peaks with retention times vs. aldrin between 10 and 25 are indicative of thepresence of chick edema factor. The screening test has been evaluated by two collaborative studies, and results indicate that the method is suitable as a screening test for chick edema factor.

Chemical Assay of Chick Edema Factor in Fats and Fatty Acids

1964 ◽  
Vol 47 (4) ◽  
pp. 772-776
Author(s):  
G R Higginbotham
Keyword(s):  
Gas Chromatography ◽  
Electron Capture ◽  
Chromatographic Method ◽  
Activated Alumina ◽  
Alumina Column ◽  
The Third ◽  
Edema Factor ◽  
Chemical Assay ◽  
Cleanup Procedure ◽  
Gas Chromatographic Method

Abstract A microcoulometric gas chromatographic method for detecting chick edema factor in fats was studied collaboratively by six laboratories. The method involved extracting unsaponifiable material from fat and fractionating it on an activated alumina column, then examining the third alumina fraction by microcoulometric gas chromatography. Results did not warrant adoption of the method. Initial studies with electron capture gas chromatography for this determination showed promise. A better cleanup procedure needs to be developed. It is planned to continue the study, and to combine acetonitrile extraction and cleanup on an acid- Celite column with electron capture determination.

Chick Edema Factor. III. Application of Microcoulometric Gas Chromatography to Detection of Chick Edema Factor in Fats or Fatty Acids

1963 ◽  
Vol 46 (3) ◽  
pp. 384-396
Author(s):  
David Firestone ◽  
Walid Ibrahim ◽  
William Horwitz
Keyword(s):  
Fatty Acids ◽  
Gas Chromatography ◽  
Screening Test ◽  
Chromatographic Method ◽  
Adsorption Chromatography ◽  
Rapid Screening ◽  
Gas Chromatograph ◽  
Edema Factor ◽  
Rapid Screening Test ◽  
Chromatographic Peaks

Abstract A rapid screening test for detecting chick edema factor in fats consists of adsorption chromatography of extracted unsaponifiables on alumina, followed by analysis of specific fractions by a microcoulometric gas chromatograph which is sensitive only to halogens. This chromatographic method appears to be more sensitive than the chick bioassay. Toxic fat yielded gas chromatographic peaks with retention times relative to aldrin of 5 or more. All samples which failed to reveal those chromatographic peaks have been shown to be nontoxic in the chick bioassay.

Detection of Chick Edema Factor and Other Chlorinated Hydrocarbons in Fats and Oils by Electron Capture Gas Chromatography: Use of TLC as a Preliminary Cleanup Procedure

1967 ◽  
Vol 50 (1) ◽  
pp. 16-21
Author(s):  
Anita Huang ◽  
David Firestone ◽  
A D Campbell
Keyword(s):  
Fatty Acids ◽  
Gas Chromatography ◽  
Electron Capture ◽  
Acid Treatment ◽  
Fats And Oils ◽  
Sulfuric Acid Treatment ◽  
Edema Factor ◽  
Cleanup Procedure ◽  
Chromatographic Procedure ◽  
Specific Fraction

Abstract A thin layer chromatographic (TLC) procedure is described for detecting chick edema factor in fats and oils. A specific fraction containing chick edema factor compounds is isolated by TLC from extracted unsaponifiables and cleaned up by sulfuric acid treatment. The residue is analyzed by electron capture gas chromatography. Results on several toxic samples of fats or fatty acids were comparable to the alumina adsorption column-electron capture gas chromatographic procedure. A 1.56% reference toxic fat sample can be detected under the conditions described. Toxicity of the specific TLC fraction was verified by tissue culture and chick embryo assay. Highly chlorinated biphenyls and naphthalenes which produce characteristic symptoms of chick edema disease at higher levels than the chick edema factor were also detected.

Fatty acid profile of milk from Nordestina donkey breed raised on Caatinga pasture

2021 ◽  
pp. 1-5
Author(s):  
Tayanna Bernardo Oliveira Nunes Messias ◽  
Susana Paula Alves ◽  
Rui José Branquinho Bessa ◽  
Marta Suely Madruga ◽  
Maria Teresa Bertoldo Pacheco ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Gas Chromatography ◽  
Milk Fat ◽  
Fat Content ◽  
Donkey Milk ◽  
Fat Percentage ◽  
Mid Infrared ◽  
Milk Samples ◽  
The Third ◽  
Commercial Viability

Abstract In this research communication we describe the composition of fatty acids (FA) present in the milk of the Nordestina donkey breed, and how they differ during lactation. Milk samples were taken from 24 multiparous lactating Nordestina donkeys that grazed the Caatinga, comprising 5 animals at each of around 30, 60 and 90 d in milk (DIM) and a further 9 animals ranging from 120 to 180 DIM. The milk fat content was analysed by mid infrared spectroscopy and the FA profile by gas chromatography. The milk fat percentage ranged from 0.45 to 0.61%. The main FA found in milk were 16:0 and 18:1c9. These did not differ among DIM classes and comprised 23% and 25% of total FA. Notably, the α-Linolenic acid (18:3 n-3) was the third most abundant FA and differed (P < 0.05) with DIM, being lowest in the 30 and 60 DIM samples (around 10.7% of total FA) and highest in the 60 and 90 DIM classes (around 14.6% of total FA). The low-fat content and the FA profile of the donkey milk gives it potential as a functional ingredient, which could help to preserve the commercial viability of the Nordestina donkey breed.

Determination of Polychlorodibenzo-p-dioxins and Related Compounds in Commercial Chlorophenols

1972 ◽  
Vol 55 (1) ◽  
pp. 85-92 ◽  
Author(s):  
David Firestone ◽  
John Ress ◽  
N L Brown ◽  
R P Barron ◽  
J N Damico
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Electron Capture ◽  
Gas Chromatography Mass Spectrometry ◽  
Alumina Column ◽  
Spectrometric Data ◽  
Chromatography Mass Spectrometry ◽  
Related Compounds ◽  
Chromatographic Mass

Abstract Twenty-one commercial chlorophenols were examined for the presence of polychlorodibenzo- p-dioxins (chlorodioxins) and related compounds. The chlorophenols were dissolved in aqueous alkali, extracted with petroleum ether, and fractionated on an alumina column. Alumina fractions were examined by electron capture gas chromatography and combined gas chromatography-mass spectrometry. Chlorodioxin content was estimated by electron capture gas chromatography. The presence of chlorodioxins, polychlorodibenzofurans (chlorofurans), and polychlorodiphenyl ethers (chloroethers) was confirmed by combined gas chromatography-mass spectrometry. The 2,3,-7,8-tetrachlorodioxin was found in 3 of 6 samples of 2,4,5-trichlorophenol but was not detected in any of the 11 samples of tetra- and pentachlorophenol that were examined. Hexachlorodioxin was present at levels ranging from 0.17 to 39 ppm in all 8 pentachlorophenols examined. Hexa-, hepta-, and octachlorodioxins as well as a wide variety of chlorofurans and chloroethers of varying chlorine content were present in most of the tetra- and pentachlorophenols. In addition, the gas chromatographic- mass spectrometric data suggested that some of the chlorophenols contained methoxy- and dimethoxypolychlorofurans and methoxypolychloroethers as well as polychlorohy droxybiphenyl.

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