Abstract
Plumeria rubraand P. alba(Family: Apocynaceae) are aromatic tropical plants widely cultivated for ornamental purposes.In Bali used as keycomponent of traditional Hindu offerings. Despite their cultural and horticultural significance, the volatile chemistry of Indonesian-grown Plumeriaflowers has not previously been characterized. Here, we comparedthe chemical composition of organic solvent extracts and the floral headspace volatiles of fresh P. rubraand P. albaflowers collected in Bali. GC-MS analysis of solvents extracts revealed that P rubrawas dominated by aromatic esters (34.15%), fatty acid methyl esters (28.42%), aromatic alcohols (12.99%), and phenolic compounds (10.90%), whereas P. albashowed a distinct profile dominated by fatty acid methyl esters (47.26%), with oxygenated monoterpenes (10.89%), aromatic alcohols (11.37%), and phenolic compounds (8.47%). HS-SPME GC-MSanalysis of fresh flowerprovided P. rubrais composed of oxygenated monoterpenes (38.49%), chiefly linalool, aromatic aldehydes (28.00%, including benzaldehyde and benzene acetaldehyde), both absentin the P. alba, which was dominated by monoterpene hydrocarbons (34.71%, primarily ocimene), undetected in P. rubra. These compositional differences underlie the sweeter, more opulent fragrance of P. rubraversus the green, fresh, citrus notes of P. alba, providingthe first chemical characterization of Plumeriaflower volatiles from Indonesia.