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Determination of tocopherols by packed column supercritical fluid chromatography [SFC]

100%

Buskov S., Jorgensen S. S., Sorensen H.

Polish Journal of Food and Nutrition Sciences

1999

tom 08

nr 3

Supercritical fluid chromatographic (SFC) separations of a-tocopheryl acetate, α-, ß-, y- and -tocopherol have been achieved on a Spherisorb S3 ODS2 column in about 15 minutes. Separation efficiency of this method has been optimised with respect to the effect of pressure, percent of methanol in the mobile phase, temperature and flow rate, resulting in theoretical plate numbers (N) varying from 63000 to 90000 per metre. Linear correlations have been found between log k' (retention factor) and fluid density for all of the tested compounds, and a van't Hoff plot yielded linear correlation between log k' and T-1 at constant mobile phase density. Linearity and repeatability were found to be acceptable with detection limits from approximately 20 ng for α-, ß-, y- and ő-tocopherol to 10 ng for a-tocopheryl acetate at a signal to noise ratio = 3. Results obtained by use of the developed SFC method to determination of tocopherols in plant oils obtained by SFE (supercritical fluid extraction) and by aqueous enzymatic processing are presented.

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Quantitative extraction of oil from plant material with supercritical carbon dioxide

100%

Buskov S., Sorensen H., Sorensen J. C., Sorensen S.

Polish Journal of Food and Nutrition Sciences

1997

tom 06

nr 3

Supercritical fluid extraction (SFE) both with CO2 and CO2/hexane has been developed as a method of analysis for lipids in cruciferous oilseed, rapeseed products and lupin. The SFE procedure used for quantitative determination of oil was compared to traditional Soxhlet oil extraction. The quantitative values obtained with SFE were equal to those obtained with the Soxhlet procedure with respect to oil and fat contents. The oil obtained by SFE had a much lower phosphorus content (below 14 mg/kg compared to 200-530 mg/kg in oil obtained with Soxhlet). When adding hexane to the supercritical fluid in concentrations varying from 50 to 150 mL/L CO2, the solubility of oil in the fluid could be raised up to 600%, from about 30 mg/g without addition of modifier to nearly 200 mg/g when using continuous addition of 150 mL hexane/ L CO2. The phosphorus content was still lower than in oil from Soxhlet (20-64 mg/kg). Therefore, extraction of oil with SFE opens the possibility for selective removal of oil before separate extraction and determination of amphiphilic compounds, e.g. phospholipids. The carotenoid and chlorophyl content in different oils from SFE and Soxhlet were evaluated by UV-VIS determinations. The presence of other amphiphilic compounds was verified and sinapic acid was found to be a quantitatively dominating phenolic compound.

Ograniczanie wyników

2 Polish Journal of Food and Nutrition Sciences

2 Buskov S.

2 Sorensen H.

1 Jorgensen S. S.

1 Sorensen J. C.

1 Sorensen S.

1 1999

1 1997

Wyniki wyszukiwania

Determination of tocopherols by packed column supercritical fluid chromatography [SFC]

Quantitative extraction of oil from plant material with supercritical carbon dioxide