The Kavalactone Content and Profile of Fiji Kava Sold on the Local Market

Abstract

Kava is the traditional intoxicating beverage of the Pacific with mild sedative and muscle relaxant effects, which are attributed to a group of compounds known as kavalactones. This paper aims to evaluate the quality of kava sold in the local markets of Fiji through the quantification of the six major kavalactones in kava root bundles and powdered kava packages using ethanolic extracts and HPLC. It was found in this work that kava root bundles contain mainly noble kava roots with a total kavalactone content of 8–13%; kavain had the highest concentration among kavalactones and kavain, methysticin, and yangonin together represented 69–71% of the total kavalactone content. Adulteration via mixing noble kava roots with those of non-noble kava with a relatively high dihydrokavain and dihydromethysticin content has also been observed. Powdered kava products were found to contain lower amounts of kavalactones (3–5%) with a less favorable kavalactone profile than those of root bundles, possibly due to mixing roots, rhizomes, and/or basal stems. The findings of this work, namely the variation in kavalactone content and profile in marketed products, indicate the need for rigorous quality control and quality indicators on kava commodities. Suggestions to include quantitative measures in the previously proposed chemical standardization code are also presented.