title: Efficacy of extracting solvents to chemical components of kava (Piper methysticum) roots.
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.
authors.affiliation: Department of Bioscience and Biotechnology, Faculty of Agriculture, University of the Ryukyus, Okinawa, 903-0213, Japan.
authors.forename: Tran Dang
authors.initials: TD
authors.lastname: Xuan
authors.forename: Masakazu
authors.initials: M
authors.lastname: Fukuta
authors.forename: Ao Chang
authors.initials: AC
authors.lastname: Wei
authors.forename: Abdelnaser Abdelghany
authors.initials: AA
authors.lastname: Elzaawely
authors.forename: Tran Dang
authors.initials: TD
authors.lastname: Khanh
authors.forename: Shinkichi
authors.initials: S
authors.lastname: Tawata
mesh_terms: D000975:Antioxidants / Q000737:chemistry* / Q000302:isolation & purification; D001713:Biphenyl Compounds; D047188:Chalcones / Q000302:isolation & purification; D002851:Chromatography, High Pressure Liquid; D016166:Free Radical Scavengers / Q000737:chemistry* / Q000302:isolation & purification; D008401:Gas Chromatography-Mass Spectrometry; D005978:Glutathione / Q000302:isolation & purification; D020901:Kava / Q000737:chemistry*; D007783:Lactones / Q000302:isolation & purification; D010636:Phenols / Q000302:isolation & purification; D010851:Picrates / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification; D018517:Plant Roots / Q000737:chemistry*; D011714:Pyrans / Q000302:isolation & purification; D011753:Pyrones / Q000302:isolation & purification; D012997:Solvents; D013010:Sonication
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D047188:Chalcones; D016166:Free Radical Scavengers; D007783:Lactones; D010636:Phenols; D010851:Picrates; D010936:Plant Extracts; D011714:Pyrans; D011753:Pyrones; D012997:Solvents; C502657:desmethoxyyangonin; C052296:7,8-dihydro-5,6-dehydrokawain; C004931:1,1-diphenyl-2-picrylhydrazyl; D005978:Glutathione; C076881:methysticin