caa a22 4500 463156137 CHVBK 20180406164734.0 cr unu---uuuuu 170326e20070901xx s 000 0 eng 10.1007/s00217-006-0506-7 doi (NATIONALLICENCE)springer-10.1007/s00217-006-0506-7 Detection of estrogenic activity in herbal teas by in vitro reporter assays [Elektronische Daten] [Hirao Kohno, Katsuyasu Kouda, Rikio Tokunaga, Yoshiaki Sonoda] Herbal teas have become popular as alternatives to caffeinated beverages during past two decades. However, toxicological studies of herbal teas have been limited and the safety of herbal teas thus remains unknown. We focused on the estrogenic activities of herbal teas since some of their ingredients are similar to those used in herbal remedies for menopause relief and therefore contain phytoestrogens. To investigate the potential estrogenic activity of extracts prepared from herbal tea mixtures commercially available and to provide useful information for the safety assessment of those products, we initially screened the estrogenic activity in extracts of 15 different herbal teas by an assay using recombinant yeast cells expressing the human estrogen receptor (YES). A distinct estrogenic activity was thus detected in the ethanolic extracts from four herbal tea mixtures. Licorice root was specified as a ingredient responsible for the estrogenic activity in those extracts. In contrast, the aqueous extracts of all herbal tea mixtures we tested exhibited distinct estrogenic activity in YES, thus suggesting the existence of various ingredients that contain estrogenic constituents extractable with water. Among them, the extract of peppermint tea exhibited the highest estrogenic activity. The estrogenic activity in extracts of herbal tea mixtures and specified ingredients were thereafter confirmed by a reporter assay system using transiently transfected HEK293 cells. Springer-Verlag, 2006 Estrogenic activity nationallicence Yeast estrogen screen nationallicence Herbal tea nationallicence Kohno Hirao Department of Hygiene, Kansai Medical University, 10-15 Fumizonocho, 570-8506, Moriguchi, Osaka, Japan aut Kouda Katsuyasu Department of Hygiene, Kansai Medical University, 10-15 Fumizonocho, 570-8506, Moriguchi, Osaka, Japan aut Tokunaga Rikio Department of Hygiene, Kansai Medical University, 10-15 Fumizonocho, 570-8506, Moriguchi, Osaka, Japan aut Sonoda Yoshiaki Department of Hygiene, Kansai Medical University, 10-15 Fumizonocho, 570-8506, Moriguchi, Osaka, Japan aut European Food Research and Technology Springer-Verlag 225/5-6(2007-09-01), 913-920 1438-2377 225:5-6<913 2007 225 217 https://doi.org/10.1007/s00217-006-0506-7 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00217-006-0506-7 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Kohno Hirao Department of Hygiene, Kansai Medical University, 10-15 Fumizonocho, 570-8506, Moriguchi, Osaka, Japan aut NATIONALLICENCE 700 1- Kouda Katsuyasu Department of Hygiene, Kansai Medical University, 10-15 Fumizonocho, 570-8506, Moriguchi, Osaka, Japan aut NATIONALLICENCE 700 1- Tokunaga Rikio Department of Hygiene, Kansai Medical University, 10-15 Fumizonocho, 570-8506, Moriguchi, Osaka, Japan aut NATIONALLICENCE 700 1- Sonoda Yoshiaki Department of Hygiene, Kansai Medical University, 10-15 Fumizonocho, 570-8506, Moriguchi, Osaka, Japan aut NATIONALLICENCE 773 0- European Food Research and Technology Springer-Verlag 225/5-6(2007-09-01), 913-920 1438-2377 225:5-6<913 2007 225 217 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer