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Transformation of tea catechins and flavonoid glycosides by treatment with Japanese post-fermented tea acetone powder


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Title: Transformation of tea catechins and flavonoid glycosides by treatment with Japanese post-fermented tea acetone powder
Authors: Tanaka, Takashi / Umeki, Hirotaka / Nagai, Sachi / Shii, Takuya / Matsuo, Yosuke / Kouno, Isao
Issue Date: 1-Sep-2012
Publisher: Elsevier Limited
Citation: Food Chemistry, 134(1), pp.276-281; 2012
Abstract: Japanese post-fermented teas are produced by a combination of aerobic and anaerobic microbial fermentation of the leaves of tea plant. Recently, it was revealed that tea products contain characteristic polyphenols identical to the tea catechin metabolites produced by mammalian intestinal bacteria, such as (2S)-1-(3′,4′,5′-trihydroxyphenyl)-3-(2″,4″,6″-trihydroxyphenyl)-propan-2-ol (EGC-M1). In the present study, degradation of epigallocatechin-3-O-gallate (EGCg) and epigallocatechin (EGC) with acetone powder prepared from Japanese post-fermented tea was examined. Under aerobic conditions, EGCg was hydrolysed to EGC and gallic acid, which were further converted to gallocatechin (GC) and pyrogallol, respectively. Under anaerobic conditions, EGCg was hydrolysed to EGC, which was further metabolised to GC, EGC-M1 and (4R)-5-(3,4,5-trihydroxyphenyl)-4-hydroxypentanoic acid (EGC-M2). Gallic acid was degraded to pyrogallol and then further decomposed. Anaerobic treatment of EGC with the acetone powder yielded EGC-M1, EGC-M2, (4R)-5-(3,4,5-trihydroxyphenyl)-γ-valerolactone, and (4R)-5-(3,4 -dihydroxyphenyl)-γ-valerolactone. Furthermore, similar anaerobic treatment of rutin and hesperidin yielded 3,4-dihydroxyphenylacetic acid and 3-(3,4-dihydroxyphenyl)propanoic acid, respectively.
Keywords: Post-fermented tea / Anaerobic fermentation / Acetone powder / Catechin metabolites / Polyphenol
URI: http://hdl.handle.net/10069/28629
ISSN: 03088146
DOI: 10.1016/j.foodchem.2012.02.136
Rights: NOTICE: this is the author’s version of a work that was accepted for publication in Food Chemistry. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Food Chemistry, 134, 1(2012)
Type: Journal Article
Text Version: author
Appears in Collections:Articles in academic journal

Citable URI : http://hdl.handle.net/10069/28629

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