As of 2021 there are 29 kavalactones in kava that have been isolated and identified.
Wang, Yingli, Chao Su, Bo Zhang, Yang Niu, Ruru Ren, Xiaojun Zhao, Lingling Yang, Wannian Zhang, and Xueqin Ma. 2021. “Biological Activity, Hepatotoxicity, and Structure-Activity Relationship of Kavalactones and Flavokavins, the Two Main Bioactive Components in Kava (Piper Methysticum).” Evidence-Based Complementary and Alternative Medicine: eCAM 2021 (August): 1–14. https://doi.org/10.1155/2021/6851798.

Wang, Yingli, Chao Su, Bo Zhang, Yang Niu, Ruru Ren, Xiaojun Zhao, Lingling Yang, Wannian Zhang, and Xueqin Ma. 2021. “Biological Activity, Hepatotoxicity, and Structure-Activity Relationship of Kavalactones and Flavokavins, the Two Main Bioactive Components in Kava (Piper Methysticum).” Evidence-Based Complementary and Alternative Medicine: eCAM 2021 (August): 1–14. https://doi.org/10.1155/2021/6851798.