HPLC coupled with electrospray (ES) MS was used to study a chloroform extract from kava roots ( PIPER METHYSTICUM). A total of thirteen kavalactones and flavokavains were identified. Seven major kavalactones, methysticin, dihydromethysticin, kavain, 7,8-dihydrokavain, 5,6-dehydrokavain, 5,6-dehydromethysticin and yangonin, were easily recognized in the extract by their [M + H] (+) or [M + Na] (+) ions, UV spectra, and retention times, compared with those of standard compounds. Six minor constituents were isolated as our own reference compounds. These constituents were identified by their [M + H] (+) or [M + Na] (+) ions, UV spectra and NMR data as 11 -hydroxy-12-methoxydihydrokavain, 7,8-dihydro-5-hydroxy-kavain, 11,12-dimethoxydihydrokavain, and flavokavains A, B and C. HPLC-ES-MS appears to be a suitable technique for identification of kavalactones and kavachalcones in the kava extract. The method also provides direct guidance for identification of other trace constituents from kava extracts.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.