title: A NMR-based, non-targeted multistep metabolic profiling revealed L-rhamnitol as a metabolite that characterised apples from different geographic origins.
abstract: This study utilises (1)H NMR-based metabolic profiling to characterise apples of five cultivars grown either in Japan (Fuji, Orin, and Jonagold) or New Zealand (Fuji, Jazz, and Envy). Principal component analysis (PCA) showed a clear separation between the Fuji-Orin-Jonagold class and the Jazz-Envy class, primarily corresponding to the differences in sugar signals, such as sucrose, glucose, and fructose. Multistep PCA removed the influence of dominant sugars and highlighted minor metabolites such as aspartic acid, 2-methylmalate, and an unidentified compound. These minor metabolites separated the apples into two classes according to different geographical areas. Subsequent partial least squares discriminant analysis (PLS-DA) indicated the importance of the unidentified metabolite. This metabolite was isolated using charcoal chromatography, and was identified as L-rhamnitol by 2D NMR and LC/MS analyses. The remarkable contribution of L-rhamnitol to geographic discrimination suggests that apples may be characterised according to various factors, including storage duration, cultivation method, and climate.
authors.affiliation: National Food Research Institute, NARO, 2-1-12 Kannondai, Tsukuba 305-8642, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Tomita
authors.affiliation: National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba 305-8566, Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Nemoto
authors.affiliation: National Food Research Institute, NARO, 2-1-12 Kannondai, Tsukuba 305-8642, Japan.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Matsuo
authors.affiliation: NARO Institute of Fruit Tree Science, 2-1 Fujimoto, Tsukuba 305-8605, Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Shoji
authors.affiliation: NARO Agricultural Research Center, 3-1-1 Kannondai, Tsukuba 305-8666, Japan.
authors.forename: Fukuyo
authors.initials: F
authors.lastname: Tanaka
authors.affiliation: National Food Research Institute, NARO, 2-1-12 Kannondai, Tsukuba 305-8642, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nakagawa
authors.affiliation: National Food Research Institute, NARO, 2-1-12 Kannondai, Tsukuba 305-8642, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ono
authors.affiliation: RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 235-0045, Japan; Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan; Graduate School of Bioagricultural Sciences and School of Agricultural Sciences, Nagoya University, 1 Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Kikuchi
authors.affiliation: National Food Research Institute, NARO, 2-1-12 Kannondai, Tsukuba 305-8642, Japan.
authors.forename: Mayumi
authors.initials: M
authors.lastname: Ohnishi-Kameyama
authors.affiliation: National Food Research Institute, NARO, 2-1-12 Kannondai, Tsukuba 305-8642, Japan; RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 235-0045, Japan. Electronic address: sekiyama@affrc.go.jp.
authors.forename: Yasuyo
authors.initials: Y
authors.lastname: Sekiyama
mesh_terms: D016002:Discriminant Analysis; D007564:Japan; D016018:Least-Squares Analysis; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D027845:Malus / Q000378:metabolism*; D008353:Mannitol / Q000378:metabolism; D013058:Mass Spectrometry / Q000379:methods; D055432:Metabolomics; D009520:New Zealand; D025341:Principal Component Analysis
chemical_list: D008353:Mannitol
keywords: Apple; Geographic origin; NMR-based metabolic profiling; PCA; PLS-DA; l-Rhamnitol; l-Rhamnitol (PubChem CID: 445052)