Toxic Nitro Compounds in Species of Astragalus (Fabaceae) in Argentina

Abstract

Thirty species of Astragalus from Argentina were analyzed for toxic aliphatic nitro compounds. Twenty-seven species, including 7 species known to poison livestock, synthesized nitro compounds that hydrolyzed to highly toxic 3-nitro-1-propanol (3-NPOH). Nitro compounds in Astragalus palenae (Phil.) Reiche hydrolyzed to both 3-NPOH and 3-nitropropionic acid (3-NPA). Astragalus palenae is the only species of Astragalus so far examined that synthesized both compounds. Analyses of leaves of the 30 species for cyanogenic glycosides were negative. Species of Astragalus from Argentina that synthesize nitro compounds should not be introduced into the United States because of their potential hazard to livestock.