High-performance liquid chromatographic-inductively coupled plasma mass spectrometric evidence for Se-"alliins" in garlic and onion grown in Se-rich soil.
Garlic and onion, are well known for their medical value, especially in against cancer and anticardiovacular diseases. "Alliins" (S-alk(en)yl-L-cysteine sulphoxides) are sources of major active compounds in Allium plants. Se incorporation into garlic significantly increases activities of garlic in cancer prevention and inhibition. Selenomethionine, selenocysteine and Se-methylselenocysteine have been identified in garlic and onion. Previously we identified gamma-glutamyl-Se-methyl-L-selenocysteine, in extracts of garlic cultivated in Se-rich soil [Med. Res. Rev. 16 (1) (1996) 111], suggesting the possible existence of Se-alk(en)yl-L-cysteine selenoxides (Se-"alliins") in garlic. Several comparative experiments were carried out to demonstrate the existence of Se-"alliins" in Se-enriched garlic and onion. We found that there was one similar time-dependent Se signal in HPLC-inductively coupled plasma MS chromatograms of cold-water extracts of freeze-dried garlic powder and fresh garlic. This signal was lost when the extracts of garlic powder and fresh garlic were stored for 1 day at >4 degrees C, but remained in fresh onion extract at the same storage conditions. These phenomena and possible mechanisms are discussed. An additional experiment showed that Allium species cultivated in Se-rich soil might contain two different Se-"alliins".
Auger
J
J
I.R.B.I. UMR 6035 CNRS, Université F. Rabelais, Parc de Grandmont, 37200 Tours, France. auger@univ-tours.fr
Yang
W
W
Arnault
I
I
Pannier
F
F
Potin-Gautier
M
M
D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003545:Cysteine / Q000031:analogs & derivatives* / Q000032:analysis*; D005737:Garlic / Q000737:chemistry* / Q000254:growth & development; D013058:Mass Spectrometry / Q000379:methods*; D019697:Onions / Q000737:chemistry* / Q000254:growth & development; D012643:Selenium / Q000032:analysis*; D012987:Soil / Q000032:analysis*
D012987:Soil; C006453:alliin; D012643:Selenium; D003545:Cysteine