title: Combined mass spectrometry-based metabolite profiling of different pigmented rice (Oryza sativa L.) seeds and correlation with antioxidant activities.
abstract: Nine varieties of pigmented rice (Oryza sativa L.) seeds that were black, red, or white were used to perform metabolite profiling by using ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and gas chromatography (GC) TOF-MS, to measure antioxidant activities. Clear grouping patterns determined by the color of the rice seeds were identified in principle component analysis (PCA) derived from UPLC-Q-TOF-MS. Cyanidin-3-glucoside, peonidin-3-glucoside, proanthocyanidin dimer, proanthocyanidin trimer, apigenin-6-C-glugosyl-8-C-arabiboside, tricin-O-rhamnoside-O-hexoside, and lipids were identified as significantly different secondary metabolites. In PCA score plots derived from GC-TOF-MS, Jakwangdo (JKD) and Ilpoom (IP) species were discriminated from the other rice seeds by PC1 and PC2. Valine, phenylalanine, adenosine, pyruvate, nicotinic acid, succinic acid, maleic acid, malonic acid, gluconic acid, xylose, fructose, glucose, maltose, and myo-inositol were significantly different primary metabolites in JKD species, while GABA, asparagine, xylitol, and sucrose were significantly distributed in IP species. Analysis of antioxidant activities revealed that black and red rice seeds had higher activity than white rice seeds. Cyanidin-3-glucoside, peonidin-3-glucoside, proanthocyanidin dimers, proanthocyanidin trimers, and catechin were highly correlated with antioxidant activities, and were more plentiful in black and red rice seeds. These results are expected to provide valuable information that could help improve and develop rice-breeding techniques.
authors.affiliation: Department of Bioscience and Biotechnology, Konkuk University, Seoul 143-701, Korea.
authors.forename: Ga Ryun
authors.initials: GR
authors.lastname: Kim
authors.affiliation: Department of Bioscience and Biotechnology, Konkuk University, Seoul 143-701, Korea.
authors.forename: Eun Sung
authors.initials: ES
authors.lastname: Jung
authors.affiliation: Department of Bioscience and Biotechnology, Konkuk University, Seoul 143-701, Korea.
authors.forename: Sarah
authors.initials: S
authors.lastname: Lee
authors.affiliation: National Academy of Agricultural Science, Rural Development Administration, Suwon 441-707, Korea.
authors.forename: Sun-Hyung
authors.initials: SH
authors.lastname: Lim
authors.affiliation: Department of Genetic Engineering and Crop Biotech Institute, College of Life Sciences, Kyung Hee University, Suwon 446-701, Korea.
authors.forename: Sun-Hwa
authors.initials: SH
authors.lastname: Ha
authors.affiliation: Department of Bioscience and Biotechnology, Konkuk University, Seoul 143-701, Korea. chlee123@konkuk.ac.kr.
authors.forename: Choong Hwan
authors.initials: CH
authors.lastname: Lee
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D013058:Mass Spectrometry; D055442:Metabolome; D055432:Metabolomics / Q000379:methods; D012275:Oryza / Q000378:metabolism*; D012639:Seeds / Q000378:metabolism*
chemical_list: D000975:Antioxidants