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Article: Simultaneous determination of cholecalciferol (vitamin [D.sub.3]) and ergocalciferol (Vitamin [D.sub.2]) in foods by selected reaction monitoring.(FOOD COMPOSITION AND ADDITIVES)(Report)
- Article from:
- Journal of AOAC International
- Article date:
- March 1, 2009
- Author:
CopyrightCOPYRIGHT 2009 AOAC International. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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Eighty years after its discovery, vitamin D deficiency is now considered a worldwide problem with health consequences (1-2). The major source of vitamin D for humans is exposure to sunlight (3-4).
Vitamin [D.sub.3] is synthesized from 7-dehydrocholesterol, a derivative of cholesterol, which is then photolyzed by UV light in a 6-electron conrotatory electrocyclic reaction (5). The previtarnin [D.sub.3] formed spontaneously isomerizes to vitamin [D.sub.3] in a [1, 7] sigmatropic shift in the epidermal layer of the skin. In summer, the excess of this fat-soluble vitamin can be stored in body fat for later use, but for most people, the body needs dietary help during ...