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Updated: Apr 2, 2026

Source and Route of Pyrrolizidine Alkaloid Contamination in Tea Samples
Published on: September 28, 2022
Chemical Constituents of Pyrrosia calvata
Abstract:
A novel flavanone glycoside, 3',5',5,7-tetrahydroxy-6-C-β-D-glucopyranosyl-flavanone (1), along with 16 known compounds, (R/S)-eriodictyol-8-C-β-D-glucopyranoside (2), quercetin-3-O-α-L-rhamnosyl (1''' --> 3''')-β-D-glucopyranoside (3), hemipholin (4), 4β-carboxymethyl-(-)-epicatechin methyl ester (5), kaempferol (6), quercetin (7), mangiferin (8), chlorogenic acid (9), 1,5-O-dicaffeoylquinic acid (10), 3,5-O-dicaffeoylquinic acid (11), 3-O-caffeoylquinic acid methyl ester (12), 1-O-caffeoyl glycoside (13), 4-O-β-D-glucopyranosyl-caffeic acid (14), 3'-O-methyleplcatechin-7-O-β-D-glucopyranoside (15), hop-22(29)-en-30-ol (16) and diploptene (17), were isolated from the whole plant of Pyrrosia calvata (Backer) Ching. Among them, compounds 2, 3, 4, 10, 11, 13 and 14 were isolated from the family Polypodiaceae for the first time, and compound 5 has not been recorded previously from the genus Pyrrosia.
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