Abstract
The chemical composition of kava (Piper methysticum) lactones and various phytochemicals obtained following the sonication of ground kava roots extracted in the solvents hexane, chloroform, acetone, ethanol, methanol and water, respectively, was analyzed. Eighteen kava lactones, cinnamic acid bornyl ester and 5,7-dimethoxy-flavanone, known to be present in kava roots, were identified, and seven compounds, including 2,5,8-trimethyl-1-naphthol, 5-methyl-1-phenylhexen-3-yn-5-ol, 8,11-octadecadienoic acid-methyl ester, 5,7-(OH)2-4′-one-6,8-dimethylflavanone, pinostrobin chalcone and 7-dimethoxyflavanone-5-hydroxy-4′, were identified for the first time. Glutathione (26.3 mg/g) was found in the water extract. Dihydro-5,6-dehydrokavain (DDK) was present at a higher level than methysticin and desmethoxyyagonin, indicating that DDK is also a major constituent of kava roots. Acetone was the most effective solvent in terms of maximum yield and types of kava lactones isolated, followed by water and chloroform, whereas hexane, methanol, and ethanol were less effective as solvents. Total phenolic and antioxidant activity varied among the extracting solvents, with acetone and chloroform producing the highest effects, followed by water, while methanol, ethanol and hexane were less effective.
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References
Bilia AR, Gallori S, Vincieri FF (2002) Kava–kava and anxiety: growing knowledge about the efficacy and safety. Life Sci 70:2581–2597
Singh YN (1992) Kava: an overview. J Ethnopharm 37:13–45
Singh YN, Blumenthal M (1997) Kava, an overview. HerbalGram 39:34–55
Chevallier A (1996) The encyclopedia of medicinal plants. DK Publ, New York
Leung AY, Foster S (1996) Encyclopedia of common natural ingredients. Wiley, New York
Mors WB, Magalhaes MT, Gottlieb OR (1962) Naturally occurring aromatic derivatives of monocyclic α-pyrones. In: Par R (ed) Progress in the chemistry of organic natural products, vol 20. Vienna New York Springer, pp 131–161
Sahelian R (1998) Clinical uses of kava. In kava, the miracle antianxiety herb. St Martin’s Press, New York, pp 85–88
Bilia AR, Bergonzi MC, Lazari D, Vinceiri FF (2002) Characterization of commercial kava–kava herbal drug and herbal drug preparations by means of nuclear magnetic resonance spectroscopy. J Agric Food Chem 50:5016–5025
Whitton PA, Lau A, Salisbury A, Whitehouse J, Evans CS (2003) Kava lactones and the kava–kava controversy. Phytochemistry 64:673–679
Stickel F, Baumuller HM, Seitz K, Vasilakis D, Seitz G, Seitz HK, Schuppan D (2002) Hepatitis induced by kava (Piper methysticum rhizoma). J Hetatol 39:62–67
Zou L, Henderson GL, Harkey MR, Sakai Y, Li A (2004) Effects of kava (kava–kava, ‘Awa', Yaqona, Piper methysticum) on c-DNA-expressed cytochrome P450 enzymes and human cryopreserved hepatocytes. Phytomedicine 11:285–294
Clouatre DL (2004) Kava kava: examining new reports of toxicity. Toxicol Lett 150:85–96
Meissner O, Haberlein H (2005) HPLC analysis of flavokavins and kavapyrones from Piper methysticum Forst. J Chromatogr B 826:46–49
Xuan TD, Elzaawely AA, Fukuta M, Tawata S (2006) Herbicidal and fungicidal activities of lactones in kava (Piper methysticum). J Agric Food Chem 54:720–725
Wu D, Nair MG, Dewitt DL (2002) Novel compounds from Piper methysticum Forst (kava kava) roots and their effect on cyclooxygenase enzyme. J Agric Food Chem 50:701–705
Dragull K, Yoshida WY, Tang CS (2003) Piperidine alkaloids from Piper methysticum. Phytochemistry 63:193–198
Tawata S, Taira S, Kobamoto N, Ishihara M, Toyama S (1996) Syntheses and biological activities of dihydro-5,6-dehydrokawain derivatives. Biosci Biotech Biochem 60:1643–1645
Kähkönen MP, Hopia AI, Vuorela HJ, Rauha J, Pihlaja K, Kujala TS, Heinonen M (1999) Antioxidant activity of plant extract containing phenolic compounds. J Agric Food Chem 47:3954–3962
Abe N, Murata T, Hirota A (1998) Novel DPPH radical scavengers, bisorbicillinol and demethltrichdimerol, from a fungus. Biosci Biotech Biochem 62:661–666
Son S, Lewis BA (2002) Free radical scavenging and antioxidative activity of caffeic acid amide and ester analogues: structure–activity relationship. J Agric Food Chem 50:468–472
Hocart HC, Fankhauser B, Buckle DW (1993) Chemical archaeology of kava, a potent brew. Rapid Commun Mass Spectrometry 7:219–224
Zhu J, Majikina M, Tawata S (2001) Syntheses and biological activities of pyranyl-substituted cinnamates. Biosci Biotech Biochem 65:161–163
Bilia AR, Scalise L, Bergonzi MC, Vincieri FF (2004) Analysis of kavalactones from Piper methysticum (kava-kava). J Chromatogr B 812:203–214
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The authors express sincere thanks to the Grand-in-Aid for Scientific Research (No. 18880020) by Japan Society for the Promotion of Science (JSPS) to Dr. Tran Dang Xuan.
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Xuan, T.D., Fukuta, M., Wei, A.C. et al. Efficacy of extracting solvents to chemical components of kava (Piper methysticum) roots. J Nat Med 62, 188–194 (2008). https://doi.org/10.1007/s11418-007-0203-2
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DOI: https://doi.org/10.1007/s11418-007-0203-2