Distribution of Organic Nitrites in Astragalus

Abstract

Leaf samples from Utah State University herbarium specimens of Astragalus were analyzed qualitatively for organic nitrites. Of 324 species and varieties examined, 69 (21%) were positive for nitrites. Excluding varieties, 251 species were examined, of which 56 (22%) contained nitrites. Organic nitrites were found to be stable in dried specimens for decades. Both recently collected and 80- to 90-year-old specimens of the same species or variety tested positive for organic nitrites. Astragalus species known to cause the loco syndrome in livestock did not contain nitrites. Only one seleniferous species, A. toanus Jones, synthesized moderate amounts of organic nitrites.