A novel acylated quercetin tetraglycoside from oolong tea (Camelia sinensis) extracts

Mihara, Rie; Mitsunaga, Tohru; Fukui, Yûkô; Nakai, Michikazu; Yamaji, Nahoko; Shibata, Hiroshi

doi:10.1016/j.tetlet.2004.04.192

Cited by 13 publications

(6 citation statements)

References 9 publications

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“…The product-ion fragment of the loss of 164 Da was also in the MS 2 spectrum. The loss of 146 and 164 Da was in keeping with the cleavage of a p -coumaroyl group and a p -coumaric acid ( − ). In the MS 3 spectrum of m / z 1079, the ion at m / z 933 had three main fragment ions at m / z 771, 753, and 301 corresponding to the loss of a 162 Da fragment, a 180 Da fragment, and a 632 Da fragment.…”

Section: Resultsmentioning

confidence: 96%

Identification and Comparison of Phenolic Compounds in the Preparation of Oolong Tea Manufactured by Semifermentation and Drying Processes

Dou

Lee

Tzen

et al. 2007

J. Agric. Food Chem.

179

135

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Oolong tea manufactured via a semifermentation process possesses a taste and color somewhere between green and black teas. Alteration of constituents, particularly phenolic compounds, in the infusion of oolong tea resulting from its manufacture, was analyzed by high-performance liquid chromatography coupled to electrospray ionization tandem mass spectrometry. The identified constituents contained 2 alkaloids, 11 flavan-3-ols, 8 organic acids and esters, 11 proanthocyanidin dimers, 3 theaflavins, and 22 flavonoid glycosides, including 6 novel acylated flavonol glycosides. The tentative structures of these 6 novel compounds were depicted according to their mass fragmentation patterns in MS(n) (n = 1-4). In comparison with caffeine as an internal standard, relative contents of the constituents in the infusions of fresh tea shoot and different oolong tea preparations were examined. Approximately, 30% catechins and 20% proanthocyanidins were oxidized during the manufacture of oolong tea from fresh tea shoots, and 20% of total flavonoids were decomposed in a follow-up drying process. Gallocatechin-3-O-gallate and theaflavins putatively produced in the semifermentation process of oolong tea were not detected in fresh tea shoots, and the majority of theaflavins were presumably transformed into thearubigins after drying.

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Section: Resultsmentioning

confidence: 96%

Identification and Comparison of Phenolic Compounds in the Preparation of Oolong Tea Manufactured by Semifermentation and Drying Processes

Dou

Lee

Tzen

et al. 2007

J. Agric. Food Chem.

179

135

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“…For four of these previous assignments, PubChem did not contain compounds that agreed with the earlier characterizations. These included two novel structures that have recently been elucidated by NMR as quercetin-3- O -(2G-p-coumaroyl( trans )-3G- O -β- l -arabinosyl-3R- O -β- d -rhamnosylrutinoside and kaempferol-3- O -(2G- p -coumaroyl( trans )-3G- O -β- l -arabinosyl-3R- O -β- d -glucosylrutinoside, , and which were not yet deposited in the PubChem database. For the remaining 85 assignments, correct chemical structures were present among the automatically generated lists of PubChem candidates, the size of which ranged from 4 to 1327 per precursor ion.…”

Section: Resultsmentioning

confidence: 99%

“…org/magma/results/ded5cb2f-c8a9-4f9f-ae11-680c25022a83. 31,32 and which were not yet deposited in the PubChem database. For the remaining 85 assignments, correct chemical structures were present among the automatically generated lists of PubChem candidates, the size of which ranged from 4 to 1327 per precursor ion.…”

Section: ■ Materials and Methodsmentioning

confidence: 99%

Automatic Chemical Structure Annotation of an LC–MSⁿ Based Metabolic Profile from Green Tea

et al. 2013

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Liquid chromatography coupled with multistage accurate mass spectrometry (LC-MS(n)) can generate comprehensive spectral information of metabolites in crude extracts. To support structural characterization of the many metabolites present in such complex samples, we present a novel method ( http://www.emetabolomics.org/magma ) to automatically process and annotate the LC-MS(n) data sets on the basis of candidate molecules from chemical databases, such as PubChem or the Human Metabolite Database. Multistage MS(n) spectral data is automatically annotated with hierarchical trees of in silico generated substructures of candidate molecules to explain the observed fragment ions and alternative candidates are ranked on the basis of the calculated matching score. We tested this method on an untargeted LC-MS(n) (n ≤ 3) data set of a green tea extract, generated on an LC-LTQ/Orbitrap hybrid MS system. For the 623 spectral trees obtained in a single LC-MS(n) run, a total of 116,240 candidate molecules with monoisotopic masses matching within 5 ppm mass accuracy were retrieved from the PubChem database, ranging from 4 to 1327 candidates per molecular ion. The matching scores were used to rank the candidate molecules for each LC-MS(n) component. The median and third quartile fractional ranks for 85 previously identified tea compounds were 3.5 and 7.5, respectively. The substructure annotations and rankings provided detailed structural information of the detected components, beyond annotation with elemental formula only. Twenty-four additional components were putatively identified by expert interpretation of the automatically annotated data set, illustrating the potential to support systematic and untargeted metabolite identification.

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“…165 Hot water extracts of oolong tea (a product of Camellia sinensis; Theaceae), which are rich in phenolics, yielded the acylated quercetin tetraglycoside, 231. 215 The p-coumaroyl group is at 2-OH of the primary sugar (b-Glcp), which is O-linked at C-3 (Fig. 1).…”

Section: Flavonol O-glycosidesmentioning

confidence: 99%

Flavonoids and their glycosides, including anthocyanins

2008

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This review describes more than 600 new examples of naturally occurring flavonoids found either as aglycones or glycosides, comprising flavones, flavonols, chalcones, dihydrochalcones, aurones, flavanones, dihydroflavonols, anthocyanidins and anthocyanins. The main topics addressed are source, identification, biological activity, biosynthesis, synthesis, and ecological or chemosystematic significance, and 514 references are cited.

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A novel acylated quercetin tetraglycoside from oolong tea (Camelia sinensis) extracts

Cited by 13 publications

References 9 publications

Identification and Comparison of Phenolic Compounds in the Preparation of Oolong Tea Manufactured by Semifermentation and Drying Processes

Identification and Comparison of Phenolic Compounds in the Preparation of Oolong Tea Manufactured by Semifermentation and Drying Processes

Automatic Chemical Structure Annotation of an LC–MSⁿ Based Metabolic Profile from Green Tea

Flavonoids and their glycosides, including anthocyanins

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A novel acylated quercetin tetraglycoside from oolong tea (Camelia sinensis) extracts

Cited by 13 publications

References 9 publications

Identification and Comparison of Phenolic Compounds in the Preparation of Oolong Tea Manufactured by Semifermentation and Drying Processes

Identification and Comparison of Phenolic Compounds in the Preparation of Oolong Tea Manufactured by Semifermentation and Drying Processes

Automatic Chemical Structure Annotation of an LC–MSn Based Metabolic Profile from Green Tea

Flavonoids and their glycosides, including anthocyanins

Contact Info

Product

Resources

About

Automatic Chemical Structure Annotation of an LC–MSⁿ Based Metabolic Profile from Green Tea