Benzaldehyde is a precursor of phenylpropylamino alkaloids as revealed by targeted metabolic profiling and comparative biochemical analyses in Ephedra spp.

► The metabolic pathway to ephedrine alkaloids was explored in Ephedra spp. ► Benzaldehyde is seemingly a metabolic precursor to ephedrine alkaloids in Ephedra. ► Benzaldehyde carboxyligase and cathinone reductase are key in ephedrine formation.