Abstract
Chemical constituents in the bulbs of Allium macrostemon Bunge were determined. From the bulbs, N-(γ-glutamyl)-S-
(E-1-propenyl)-cysteine (Glu-PEC), trans-S-1-propenyl-cysteine (PEC), tryptophan, γ-glutamyl-tryptophan and γ-glutamylphenylalanine
were isolated and the chemical structures were identified by their NMR spectral data. Amongst them, Glu-PEC
showed the highest concentration (1.07 g / kg fresh weight) in the bulb. The metabolites pattern in the bulbs was compared with that
in the leaves by HPLC analysis. Some phenolic compounds such as allimacronoid A, tuberonoid A, kaempferol 3-O-sophoroside
and kaempferol 3-O-glucoside, which have been found in the leaves, were not detected in the bulbs.
