Identification of proprionylcholine in higher plants

Propionylcholine, a novel analogue of acetylcholine, was identified in green plants by gas chromatography/mass spectrometry. Propionylcholine was found in the leaves of the following species previously shown to contain acetylcholine and cholinesterase activity: Codiaeum variegatum Blume, Phaseolus aureus Roxb. cv. Berken, Plantago rugelli Decne., Populus grandidentata Michx., and Betula pendula Roth. The quantities of propionylcholine ranged from a high of 2.3 nmol (g fresh weight)−1 in C. variegatum to a low of 0.11 nmol (g fresh weight)−1 in P. rugelli. These amounts represented 6 to 8% of the levels of acetylcholine. In contrast to animal tissues which rarely synthesize propionylcholine, this compound was found in all species examined which represented five families of flowering plants.