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Updated: Jun 26, 2026

Preparation and In Vivo Use of an Activity-based Probe for N-acylethanolamine Acid Amidase
Published on: November 23, 2016
Azetidine-2-carboxylic acid in the food chain
Edward Rubenstein1, Theresa McLaughlin, Richard C Winant
1Department of Medicine, Stanford University School of Medicine, Stanford, CA 94305, United States. exr@stanford.edu
Abstract:
Azetidine-2-carboxylic acid (Aze) 1 is a non-protein amino acid present in sugar beets and in table beets (Beta vulgaris). It is readily misincorporated into proteins in place of proline 2 in many species, including humans, and causes numerous toxic effects as well as congenital malformations. Its role in the pathogenesis of disease in humans has remained unexplored. Sugar beet agriculture, especially in the Northern Hemisphere, has become widespread during the past 150 years, and now accounts for nearly 30% of the world's supply of sucrose. Sugar beet byproducts are also used as a dietary supplement for livestock. Therefore, this study was undertaken as an initial survey to identify Aze-containing links in the food chain. Herein, we report the presence of Aze 1 in three sugar beet byproducts that are fed to farm animals: sugar beet molasses, shredded sugar beet pulp, and pelleted sugar beet pulp.
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