Table 2.
Transition ions, retention times (for each conjugation position), and relative contents of green tea catechins (GTCs) metabolites from the samples taken from the apical sides after loading catechins in the basolateral side. The relative content of the catechin metabolites were measured as free-form equivalents, relative to the internal standard (ethyl gallate). Each value was the average of three different samples. * and ** indicate significantly different at a 0.05 and 0.01 level between the metabolites from cis and trans catechins, respectively. Me indicates methyl; ND indicates not detected.
Compound Name | Detected Mass (ESI-) | MS/MS Fragments (Collision Energy) | Retention Time (min) | Relative Content (nmol) | Significance |
---|---|---|---|---|---|
C-O-sulfate | 369.0279 | 289, 231, 109 (20 V) | 3.86 | 541.57 ± 65.43 | * |
EC-O-sulfate | 369.0285 | 289, 245,137 (20 V) | 6.69 | 202.50 ± 12.58 | |
O-me-C | 303.0879 | 248, 203, 159, 101, 73 (1 0V) | 3.86, 9.25 | 41.07 ± 3.66 | * |
O-me-EC | 303.089 | 248, 159, 73 (10 V) | 7.40, 12.64 | 22.33 ± 1.85 | |
O-me-C-O-sulfate | ND | ND | ND | ND | |
O-me-EC-O-sulfate | ND | ND | ND | ND | |
GC-O-sulfate | 385.024 | 305, 261, 125 (20 V) | 2.19 | 510.85 ± 61.72 | ** |
EGC-O-sulfate | 385.0246 | 305, 219, 154 (20 V) | 2.54 | 31.77 ± 1.97 | |
O-me-GC | 319.0523 | 303, 194, 105 (10 V) | 2.17, 7.47 | 18.54 ± 1.74 | * |
O-me-EGC | 319.0523 | 253, 183, 93 (10V) | 2.35, 8.10 | 30.10 ± 3.35 | |
O-me-GC-O-sulfate | 399.0395 | 385, 288, 124 (10 V) | 2.20, 3.25 | 79.42 ± 6.50 | * |
O-me-EGC-O-sulfate | 399.0404 | 319, 253, 183, 93 (10 V) | 2.52, 4.23 | 23.14 ± 1.60 | |
CG-O-sulfate | 521.0416 | 441, 369, 289, 249, 169, 64 (20 V) | 13.61 | 366.00 ± 44.22 | ** |
ECG-O-sulfate | 521.0406 | 441, 331, 289, 169, 125 (20 V) | 16.28 | 7.25 ± 0.45 | |
O-me-CG | 455.0998 | 439, 382, 271, 169, 125, 58 (20 V) | 14.69, 18.65, 19.08 | 50.78 ± 5.44 | * |
O-me-ECG | 455.0989 | 352, 183, 109 (20 V) | 14.13, 17.14 | 10.02 ± 0.80 | |
O-me-CG-O-sulfate | 535.0567 | 455, 397, 303, 198, 141, 89 (10 V) | 15.69, 17.11 | 62.89 ± 6.10 | |
O-me-ECG-O-sulfate | ND | ND | ND | ND | |
GCG-O-sulfate | 537.0362 | 457, 395, 305, 216, 169, 125 (10 V) | 7.48, 8.79, 9.76 | 216.70 ± 20.73 | ** |
EGCG-O-sulfate | 537.0376 | 457, 287, 169, 113 (10 V) | 10.4 | 6.87 ± 0.55 | |
O-me-GCG | 471.0931 | 402, 287, 125 (10 V) | 9.82, 14.61, 15.12 | 35.23 ± 3.67 | * |
O-me-EGCG | 471.0954 | 305, 113 (10 V) | 7.81, 12.19 | 11.51 ± 1.11 | |
O-me-GCG-O-sulfate | 551.0513 | 464, 399, 369, 324, 205, 157, 77 (10 V) | 11.84, 13.50, 14.68 | 96.48 ± 7.80 | |
O-me-EGCG-O-sulfate | ND | ND | ND | ND |