4″-Sulfation Is the Major Metabolic Pathway
of Epigallocatechin-3-gallate in Humans: Characterization of Metabolites,
Enzymatic Analysis, and Pharmacokinetic Profiling

Akane Hayashi; Shimpei Terasaka; Yuko Nukada; Akiyo Kameyama; Masayuki Yamane; Ryuta Shioi; Masazumi Iwashita; Kohjiro Hashizume; Osamu Morita

doi:10.1021/acs.jafc.2c02150

Table 1

¹H NMR Data of EGCG and EGCG-Sulfate Generated by Human SULTs^a

	EGCG	EGCG-sulfate, extract by human SULT
position	¹H (CD3CN)	¹H (CD3CN)	Δδ
2	4.99(s)	5.00(s)	0.01
3	5.47(s)	5.48(s)	0.01
4	2.80(dd, J = 2.2, 17.6 Hz)	2.80(dd, J = 2.2, 17.6 Hz)	0.00
	2.95(dd, J = 4.6, 17.4 Hz)	2.96(dd, J = 4.5, 17.4 Hz)	0.01
6	6.00(d, J = 2.3 Hz)	6.00(d, J = 2.3 Hz)	0.00
8	5.96(d, J = 2.3 Hz)	5.97(d, J = 2.4 Hz)	0.01
2′	6.50(s)	6.50(s)	0.00
6′	6.50(s)	6.50(s)	0.00
2″	6.91(s)	6.87(s)	–0.04
6″	6.91(s)	6.87(s)	–0.04

^aEach number and notation denote chemical shift (ppm), peak splitting, and coupling constants (J) in turn. Δδ represents the differences in chemical shift values in EGCG-sulfate compared with EGCG. s, singlet; d, doublet; and dd, doublet of doublets.