Production of kavapyrones by Kava (Piper methysticum) tissue cultures

Kava (Piper methysticum) is extensively used for the generation of a ceremo nial intoxicating beverage in South Pacific Island cultures and for the pro duction of a sedating phytomedicine worldwide. Callus cultures were success fully initiated from shoot explants of Kava cvs. Makea and Awke and from le af explants of cv. Awke. Bacterial and fungal contamination were decreased- by multiple steps of tissue sterilization and the inclusion of a biocide in the medium. The production of kavapyrones by the Kava callus cultures was measured relative to the levels of these chemicals generated by intact plan t tissues. The results showed that total kavapyrone production in callus cu ltures was less than 1 % of that observed for root tissue from which the ph ytomedicine and intoxicating beverage is typically produced. Although callu s cultures were initiated from stem and leaf explant materials, the corresp onding callus cultures yielded a relative pattern of kavapyrone production similar to that of root extracts, with kavain and methysticin present as th e predominate kavapyrones. This differed from stem tissues and the reported values for leaf tissues, where dihydrokavain and dihydromethsticin represe nt the predominant kavapyrones.