Comprehensive metabolites characterization of Alpinia katsumadai seeds via a multiplex approach of UHPLC-MS/MS and GC-MS techniques.

Alpinia katsumadai Hayata (Zingiberaceae) is an edible seed valued in traditional medicine for its remarkable therapeutic properties. The seed serves as a fragrant culinary spice, adding a unique flavor to various foods. In this study, three approaches were employed to elucidate seed metabolome including UHPLC-MS/MS-based molecular networking, HS-SPME/GC-MS, and post-silylation GC-MS. A total of 82 secondary metabolites spanning diverse chemical classes were annotated, including the report of two newly annotated catechin-guibourtinidol derivatives and deoxy phloretin-3'-C-hexoside for the first time in Alpinia genus, alongside the first hypothesis of calyxins' class mass fragmentation pattern. HS-SPME/GC-MS analysis led to the detection of 30 aroma determinants dominated by sesquiterpenes (55.1%) and monoterpenes (36.8%). Daucene and α-phellandrene were detected at 274.41 µg/g and 161.25 µg/g, respectively, and to likely account for seed aroma. GC-MS post-silylation dissected 48 metabolites, revealing the abundance of sugars, arylheptanoids, and flavonoids, with sucrose as major sugar (23.81 mg/g), and cardamonin, as major flavonoid. Such comprehensive phytochemical mapping provides critical insights into A. katsumadai seed metabolome, offering novel evidence for its health-promoting and culinary qualities.