Fig. 2.
Identification of green tea catechin metabolites for the individual subjects in plasma, blister fluid and biopsy samples postsupplementation (after 3 months), with or without UVR. As peak areas for the conjugated green tea metabolites in the plasma were larger, plasma is presented as peak area ×10−2, blister analysis as peak area ×10−6 and biopsy analysis as peak area ×10−7 (relative to the internal standard, 2 μg/ml EG). Hippuric acid is presented as micromolars (μM) for plasma data and as nanomolars (nM) for blister analysis. The metabolites identified in subjects for more than one biological sample that are displayed are EC-O-sulfate, O-Me-EC-O-sulfate, O-Me-EGC-O-sulfate, EGC-O-glucuronide, O-Me-GA-O-sulfate, M4-O-sulfate, M6/M6′-O-sulfate and hippuric acid. EC-O-glucuronide, O-Me-M4-O-sulfate, M4-O-glucuronide, M6/M6′-O-glucuronide and benzoic acid-O-sulfate were also present in more than one biological sample. EGCG and 3-hydroxybenzoic acid sulfate were identified in more than one biological sample for one volunteer only. Only O-Me-EC-O-sulfate, O-Me-GA-O-sulfate and M6/M6′-O-sulfate graphs show biopsy data. EC, epicatechin; EG, ethyl gallate; EGC, epigallocatechin; EGCG, epigallocatechin gallate; GA, gallic acid; IS, internal standard; Me, methyl; V, volunteer number.