Table 4 Biomarkers of tea intake discovered in observational studies
From: Biomarkers of intake for coffee, tea, and sweetened beverages
Type of beverage | No. subjects | Sample type | Analytical method | Enzymatic hydrolysis | Discriminating metabolites/candidate biomarkers (HMDB ID if available) | Association with | Reference |
|---|---|---|---|---|---|---|---|
Black tea | 232 | Urine (24Â h) | GC-MS | Yes | 4-O-Methylgallic acid (HMDB0013198) | 24-HDR | [132] |
Black tea | 53 | Urine (24Â h and spot) | LC-MS | Yes | Gallic acid (HMDB0005807), 4-O-methylgallic acid (HMDB0013198) | 2-Day dietary record | [33] |
Green tea | 968 | Urine | LC-MS | Yes | Epicatechin (HMDB0001871), (−)-epigallocatechin (HMDB0038361), 4’-O-methylepigallocatechin (not in HMDB), 5-(3′,4′,5′-trihydroxyphenyl)-γ-valerolactone (HMDB0041691), 5-(3′,4′-dihydroxyphenyl)-γ-valerolactone (HMDB0029185) | FFQ | [71] |
Green tea, black tea | 119 | Urine (24Â h) | LC-MS | Yes | Kaempferol (HMDB0005801) | FFQ, 4-day food diary | [75] |
Green tea | 660 | Urine (spot, non-fasting) | HPLC | Yes | Epicatechin (HMDB0001871), (−)-epigallocatechin (HMDB0038361), 4’-O-methylepigallocatechin (not in HMDB), 5-(3′,4′,5′-trihydroxyphenyl)-γ-valerolactone (HMDB0041691), 5-(3′,4′-dihydroxyphenyl)-γ-valerolactone (HMDB0029185) | FFQ | [72] |
Tea | 191 | Urine (24Â h, overnight) | LC-MS | Yes | Kaempferol (HMDB0005801) | FFQ | [133] |
Tea | 476 | Urine (24 h) | LC-MS | No | Methyl(epi)catechin sulfate (not in HMDB), hydroxyphenylvaleric acid glucuronide (not in HMDB), dihydroxyphenyl-γ-valerolactone glucuronide and sulfate (HMDB0041693, HMDB0029191), 4-O-methylgallic acid (HMDB0013198), methylgallic acid sulfate(HMDB0060005), pyrogallol sulfate (HMDB0060016) | 24-HDR | [37] |