A genetic mutation that reduces calcium oxalate content increases calcium availability in Medicago truncatula
Paul A. Nakata A B and Michele M. McConn AA USDA / ARS Children’s Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030-2600, USA.
B Corresponding author. Email: pnakata@bcm.tmc.edu
Functional Plant Biology 33(7) 703-706 https://doi.org/10.1071/FP06068
Submitted: 30 March 2006 Accepted: 10 May 2006 Published: 3 July 2006
Abstract
Oxalate is considered an antinutrient that renders calcium unavailable for nutritional absorption by humans. Efforts have been made to generate and identify edible plants with decreased levels of this antinutrient. The extent to which a food can be nutritionally improved through genetic alterations in calcium oxalate content, however, has not been determined. The recent identification of near isogenic lines of the forage legume, Medicago truncatula Gaertn. (cv. Jemalong genotype A17), that differ in calcium oxalate content aids in filling this gap in our knowledge. In this study, we use an in vitro dialysis system to show that the decrease in calcium oxalate results in an enhancement in calcium availability. By comparing virtually identical plants a more direct assignment of the calcium availability to the presence or absence of oxalate was made. In addition, this study shows, for the first time, the feasibility of improving plant foods through the genetic manipulation of its oxalate content.
Acknowledgments
This work was supported in part by the US Department of Agriculture, Agricultural Research Service, under Cooperative Agreement 58-6250-6-001 and NIH 1R01 DK 062366. The contents of this publication do not necessarily reflect the views or policies of the US Department of Agriculture, nor does mention of trade names, commercial products, or organisations imply endorsement by the US Government.
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