The results of the study demonstrated that the method is fit for the purpose of determining methysticin
, dihydromethysticin, kavain, dihydrokavain, yangonin, desmethoxyyangonin, flavokavain A, flavokavain B, and flavokavain C in kava raw material and finished products (dry-filled capsule, liquid phytocaps, and tincture).
, kavain, and yangonin have been reported to induce ERK1/2 phosphorylation, while dihydro-5,6-dehydrokavain and desmethoxyyangonin have been shown to inhibit peroxide-induced P38 phosphorylation .
Fendt et al., "Oral administration of methysticin
improves cognitive deficits in a mouse model of Alzheimer's disease," Redox Biology, vol.
The bioactive chemical constituents from Kava are the kava lactones, particularly kavain, dihyd rokava in, yangonin, dimethoxyyangonin, methysticin
and dihydromethysticin (Fig.
The active constituents (secondary metabolites) are the fat soluble kava lactones (kavapyrones), and the main compounds are methysticin
, dihydromethisticin, kavain, dihydrokavain and desmethoxyangonin and flavonoids (flavokavains) (Braun 2007).
The kava shrub (piper methysticin
) is native to Polynesia and the Pacific Islands.
Eight-day-old chicks received intraperitoneal injections of either vehicle, chlordiazepoxide (5.0mg/ml/kg), Piper methysticum extract (containing 30% kavalactones), kavain, dihydrokavain, methysticin
, dihydromethysticin, yangonin, or desmethoxyyangonin, (30mg/ml/kg for kava compounds) 30 minutes prior to being tested in the presence of two conspecifics or in isolation for a three minute observation period.
There are six major kavalactones in kava: yangonin, methysticin
, kavain, dihydromethysticin (DHM), dihydrokavain and demethoxy-yangonin.
Yangonin, demethoxyyangonin, methysticin
, dihy-dromethysticin, kavain, and dihydrokavain were identified in the largest peaks, accounting for 96% of the total kavalactones.
1997; Lebot 2006; Schmidt 2007; WHO 2007): kavain (K), dihydrokavain (DHK), methysticin
(M), dihydromethysticin (DHM), yangonin (Y), and desmethoxyyango-nin (DMY).
, dihydromethysticin, kavain and dihydrokavain were detected at 240 nm, demethoxyyangonin and yangonin at 360 nm.
Ethanolic kava extract and the kavalactones methysticin
, yangonin, and desmethoxy-yangonin were previously shown not to be activated to toxic metabolites in cultured human lymphoblastoid MCL-5 cells stably transfected with human cytochrome P450 enzymes (1A1, 1A2, 2A6, 2E1, 3A4) and human epoxide hydrolase (Zou et al., 2004).