Polyphenols in lahpet-so and two new catechin metabolites produced by anaerobic microbial fermentation of green tea.
The phenolic constituents of lahpet-so, a traditional postfermented tea of Myanmar produced under anaerobic conditions, were examined. The major polyphenols were identified to be pyrogallol and 4'-hydroxyphenyl-3-(2'',4'',6''-trihydroxyphenyl)-propan-2-ol, 3',4'-dihydroxyphenyl-3-(2'',4'',6''-trihydroxyphenyl)-propan-2-ol, and 3',4',5'-trihydroxyphenyl-3-(2'',4'',6''-trihydroxyphenyl)-propan-2-ol. The hydroxydiphenylpropan-2-ols were identical to the initial metabolites produced from green tea catechins by mammalian intestinal bacteria. In addition, an anaerobic mixed-fermentation experiment using lahpet-so and Japanese commercial green tea afforded two new catechin degradation products together with known compound bruguierol B and the above-mentioned catechin metabolites. Based on spectroscopic evidence, the structures of the new compounds were concluded to be 4-(2,5-dihydroxyhexyl)benzene-1,2-diol and (5S,8R)-6,7,8,9-tetrahydro-5-methyl-5·8-epoxy-5H-benzocycloheptene-2,3,4-triol. Interestingly, the production mechanism was deduced to be the inverse of the biosynthesis of the flavan-3-ol A ring.
Graduate School of Biomedical Sciences, Nagasaki University, Bunkyo-Machi 1-14, Nagasaki, 852-8521, Japan.
Takuya
T
Shii
Chiori
C
Asada
Yosuke
Y
Matsuo
Yoshinori
Y
Saito
Takashi
T
Tanaka
D000818:Animals; D001419:Bacteria / Q000378:metabolism; D001555:Benzene Derivatives / Q000737:chemistry* / Q000378:metabolism; D003508:Cycloheptanes / Q000737:chemistry* / Q000378:metabolism; D005285:Fermentation; D059808:Polyphenols / Q000737:chemistry* / Q000378:metabolism; D013662:Tea / Q000737:chemistry* / Q000378:metabolism
C000590725:(5S,8R)-6,7,8,9-tetrahydro-5-methyl-5,8-epoxy-5H-benzocycloheptene-2,3,4-triol; C000590724:4-(2,5-dihydroxyhexyl)benzene-1,2-diol; D001555:Benzene Derivatives; D003508:Cycloheptanes; D059808:Polyphenols; D013662:Tea