title: 1HNMR-Based Discriminatory Analysis of Eurycoma longifolia from Different Locations and Establishing a Profile for Primary Metabolites Identification and Quassinoids Quantification.
abstract: Quassinoids, the major secondary metabolites ofEurycoma longifoliaroots, improve male fertility. Hence, it is crucial to investigate their quantitative level inE. longifoliaextracts. A profile was established to identify the primary metabolites and major quassinoids, and quantify quassinoids using external calibration curves. Furthermore, the metabolic discrimination ofE. longifoliaroots from different regions was investigated. The1H-NMR spectra of the quassinoids, eurycomanone, eurycomanol, 13,21-dihydroeurycomanone, and eurycomanol-2-O-β-D-glycopyranoside were obtained. The1H-NMR profiles ofE. longifoliaroot aqueous extracts from Perak (n = 30) were obtained and used to identify primary metabolites and the quassinoids. Selangor, Kedah, Terengganu (n = 5 for each), and Perak samples were checked for metabolic discrimination. Hotelling's T2plot was used to check for outliers. Orthogonal partial least-squares discriminant analysis was run to reveal the discriminatory metabolites. Perak samples contained formic, succinic, methylsuccinic, fumaric, lactic, acetic and syringic acids as well as choline, alanine, phenylalanine, tyrosine,α-glucose, eurycomanone, eurycomanol, 13,21-dihydroeurycomanone, and eurycomanol-2-O-β-D-glycopyranoside. The extracts from other locations contained the same metabolites. The limit of quantification values were 1.96 (eurycomanone), 15.62 (eurycomanol), 3.91 (13,21-dihydroeurycomanone), and 31.25 (eurycomanol-2-O-β-D-glycopyranoside) ppm. The Hotelling's T2plot revealed no outlier. The orthogonal partial least-squares discriminant analysis model showed that choline, eurycomanol, eurycomanol-2-O-β-D-glycopyranoside, and lactic and succinic acid levels were different among regions. Terengganu and Perak samples contained higher amounts of eurycomanol and eurycomanol-2-O-β-D-glycopyranoside, respectively. The current approach efficiently detectedE. longifoliaroot metabolites, quantified the quassinoids, and discriminatedE. longifoliaroots from different locations. These findings could be applicable to future research onE. longifoliawhere the higher content of quassinoids is required.
authors.affiliation: Department of Pharmaceutical Chemistry, School of Pharmaceutical Sciences, Universiti Sains Malaysia, Penang, Malaysia.
authors.forename: Forough
authors.initials: F
authors.lastname: Ebrahimi
authors.affiliation: Department of Pharmaceutical Chemistry, School of Pharmaceutical Sciences, Universiti Sains Malaysia, Penang, Malaysia.
authors.forename: Baharudin
authors.initials: B
authors.lastname: Ibrahim
authors.affiliation: Bruker Malaysia Sdn Bhd, Selangor, Malaysia.
authors.forename: Chin Hoe
authors.initials: CH
authors.lastname: Teh
authors.affiliation: Department of Pharmaceutical Chemistry, School of Pharmaceutical Sciences, Universiti Sains Malaysia, Penang, Malaysia.
authors.forename: Vikneswaran
authors.initials: V
authors.lastname: Murugaiyah
authors.affiliation: Department of Pharmaceutical Chemistry, School of Pharmaceutical Sciences, Universiti Sains Malaysia, Penang, Malaysia.
authors.forename: Chan Kit
authors.initials: CK
authors.lastname: Lam
mesh_terms: D035701:Eurycoma / Q000737:chemistry / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D055432:Metabolomics / Q000379:methods*; D015394:Molecular Structure; D010936:Plant Extracts / Q000737:chemistry* / Q000302:isolation & purification; D018517:Plant Roots / Q000737:chemistry / Q000378:metabolism; D036702:Quassins / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D010936:Plant Extracts; D036702:Quassins; C506425:eurycomanone; C093532:eurycomanol