Quantitative analysis of beta-sitosterol oxides induced in vegetable oils by natural sunlight, artificially generated light, and irradiation.
UV radiation is able to induce lipid peroxidation. Photooxidation-induced beta-sitosterol oxides were monitored in four vegetable oils exposed to sunlight for 10, 20, and 30 days during May 2005 (northeastern France), exposed to artificial light generated by a high-pressure Hg lamp for 21, 42, and 63 h at room temperature, and exposed to a 10 MeV electron beam at 0.93, 2.69, and 9.30 kGy at 8 degrees C. Quantification was performed by capillary gas chromatography-mass spectrometry according to the total ion current mode and using a reconstructed ion trace chromatogram with specific ion fragments. Sunlight induced the formation of higher amounts of oxides than UV light, while no significant oxidizing effect was observed with electron beam irradiation. However, data suggested that the amount of the main oxides formed was strongly dependent on the dose rate (length of exposure). Accordingly, shorter but more intense treatments had lower oxidizing effects.
Zhang
Xin
X
Laboratoire de Chimie Analytique et Sciences de l'Aliment (UMR 7178), Faculté de Pharmacie, Université Louis Pasteur, Illkirch, and Laboratoire d'Oncologie Nutritionnelle, EA 3430/IRCAD, 1 place de l'Hôpital, Strasbourg, France.
Julien-David
Diane
D
Miesch
Michel
M
Raul
Francis
F
Geoffroy
Philippe
P
Aoude-Werner
Dalal
D
Ennahar
Saïd
S
Marchioni
Eric
E
D005229:Fatty Acids, Monounsaturated; D008401:Gas Chromatography-Mass Spectrometry; D008027:Light; D015227:Lipid Peroxidation / Q000528:radiation effects; D000069463:Olive Oil; D010087:Oxides / Q000032:analysis*; D010777:Photochemistry; D010938:Plant Oils / Q000737:chemistry* / Q000528:radiation effects*; D000074262:Rapeseed Oil; D012855:Sitosterols / Q000032:analysis* / Q000737:chemistry*; D013024:Soybean Oil / Q000737:chemistry; D000074242:Sunflower Oil; D013472:Sunlight; D014466:Ultraviolet Rays
D005229:Fatty Acids, Monounsaturated; D000069463:Olive Oil; D010087:Oxides; D010938:Plant Oils; D000074262:Rapeseed Oil; D012855:Sitosterols; D000074242:Sunflower Oil; C025473:gamma-sitosterol; D013024:Soybean Oil