Table 1 Metabolites identified in human intervention studies on coffee
From: Biomarkers of intake for coffee, tea, and sweetened beverages
| Beverage | No. subjects | Sample type | Analytical method | Enzymatic hydrolysis | Discriminating metabolites/candidate biomarkers | Reference |
|---|---|---|---|---|---|---|
| Instant coffee (repeated intake) | 5 | Urine | HPLC | Yes | Ferulic, isoferulic, dihydroferulic, vanillic acids, 3-hydroxyhippuric acid | [25] |
| Instant coffee | 9 | Urine | LC-MS | Yes | Chlorogenic acid, caffeic acid, m-coumaric acid | [26] |
| Coffee | 13 | Urine | CE-MS | No | Coumaric acid, caffeic acid | [127] |
| Instant coffee | 11 | Plasma, urine | LC-MS | No | Ferulic and dihydroferulic acid sulfates (blood and urine), feruloylglycine (urine only) | [27] |
| Filter coffee | 9 | Urine | LC-MS | No | Trigonelline, N-methylpyridium | [35] |
| Filter coffee | 13 | Plasma | LC-MS | No | Trigonelline, dimethylxanthines, methylxanthines, dihydroferulic acid, dihydrocaffeic acid sulfate, ferulic acid glucuronide, ferulic acid sulfate, ferulic acid, dihydroferulic acid sulfate, dihydroferulic acid glucuronide, N- feruloylglycine | [29] |
| Instant coffee | 11 | Plasma, urine | LC-MS | No | 3-, 4- and 5-Feruloylquinic acid, 3 and 4-Caffeoylquinic acid lactone sulfate (urine and plasma), isoferulic acid-3-glucuronide (urine only) | [28] |
| Coffee (repeated intake) | 8 | Urine | 1H-NMR | No | 2-Furoylglycine | [30] |