JACN Did you know that you can get alerts when a new issue is online?
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Figures Only
Right arrow Full Text
Right arrow Full Text (PDF)
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Rocheford, T. R.
Right arrow Articles by Lambert, R. J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Rocheford, T. R.
Right arrow Articles by Lambert, R. J.
Journal of the American College of Nutrition, Vol. 21, No. 90003, 191S-198S (2002)
Published by the American College of Nutrition

Enhancement of Vitamin E Levels in Corn

Torbert R. Rocheford, PhD, Jeffrey C. Wong, PhD, Cem O. Egesel, PhD and Robert J. Lambert, PhD

Department of Crop Sciences, University of Illinois, Urbana, Illinois

Address reprint requests to: T. Rocheford, PhD, Department of Crop Sciences, AW-101 Turner Hall, 1102 South Goodwin Ave., University of Illinois, Urbana 61801. E-mail: trochefo{at}uiuc.edu

Vitamin E is the common name that describes eight naturally occurring compounds possessing {alpha}-tocopherol activity. These eight vitamin E compounds are collectively termed tocols, and all have antioxidant activity. There is natural variation among different corn breeding lines for levels of tocols. The two predominant isomers present in corn grain are {gamma}-tocopherol and {alpha}-tocopherol. {alpha}-tocopherol is considered more desirable for human and animal consumption because it has higher biological activity than {gamma}-tocopherol. Most corn breeding lines naturally have much more {gamma}-tocopherol than {alpha}-tocopherol. Therefore a breeding goal is to increase levels of {alpha}-tocopherol relative to {gamma}-tocopherol. However, recent research suggests that {gamma}-tocopherol and compounds metabolized from it have properties important to human health that are unique from properties of {alpha}-tocopherol. Therefore it may be desirable to not only increase levels of {alpha}-tocopherol in corn grain, but also levels of {gamma}-tocopherol. Determination of levels of tocopherols in corn grain is very laborious, requires HPLC analysis and is too time consuming for use in routine commercial corn breeding programs. Therefore we are performing biotechnology enabled molecular marker mapping of chromosomal regions with genes that control levels and ratios of {alpha}- and {gamma}-tocopherol. Breeders can use molecular markers we have identified to expediently select for desirable alleles of genes that will improve levels of {alpha}- and {gamma}-tocopherol in corn grain, without having to perform laborious HPLC assays. Another biotechnology strategy we have initiated is genetic transformation of corn with the {gamma}-tocopherol methyl transferase gene to enhance conversion of {gamma}-tocopherol to {alpha}-tocopherol and thus increase levels of {alpha}-tocopherol. This transgenic strategy has been demonstrated in the model plant Arabidopsis, and we are now applying this approach to corn.

Key words: alpha ({alpha})-tocopherol, corn, gamma ({gamma})-tocopherol, quantitative trait loci (QTL), transgenics, vitamin E






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2002 by the American College of Nutrition.