3-N-oxalyl-L-2,3-diaminopropanoic acid (-ODAP ) is a neuroexcitatory non-protein amino acid identified in grass pea (Lathyrus sativus L.) and in ginseng (Panax spp). Its presence in the drought tolerant grass pea is thought to be responsible for the crippling disease neurolathyrism, while in the lon...