Plant calcium oxalate crystal formation, function, and its impact on human health

Abstract

Crystals of calcium oxalate have been observed among members from most taxonomic groups of photosynthetic organisms ranging from the smallest algae to the largest trees. The biological roles for calcium oxalate crystal formation in plant growth and development include high-capacity calcium regulation, protection against herbivory, and tolerance to heavy metals. Using a variety of experimental approaches researchers have begun to unravel the complex mechanisms controlling formation of this biomineral. Given the important roles for calcium oxalate formation in plant survival and the antinutrient and pathological impact on human health through its presence in plant foods, researchers are avidly seeking a more comprehensive understanding of how these crystals form. Such an understanding will be useful in efforts to design strategies aimed at improving the nutritional quality and production of plant foods.

Key words： calcium; oxalate; crystals; biomineral; idioblast; nutrition

Acknowledgments

Thanks go to Michele McConn, Bin Luo, and Justin Foster for comments on the manuscript. 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 organizations imply endorsement by the US Government. This research was supported in part by the US Department of Agriculture, Agricultural Research Service, under Cooperative Agreement number 58-6250-0-008.

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