Coptis chinensis Franch. - Ranunculaceae - 黄连 huang lian (chin.), Chinese goldthread, Goldfaden

Perennial herb, native to Asia (China, Myanmar, India); leaves ovate-triangular, papery to subleathery, abaxially glabrous, adaxially sparsely puberulous on veins, lateral segments slightly shorter than central one, obliquely ovate, unequally 2-parted; central segment petiolulate, ovate-rhombic; inflorescences 3-8-flowered; sepals 5, greenish yellow, petals linear-lanceolate, 5-6.5mm, glabrous, apex attenuate.
http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=200007765

„The rhizomes of Coptis chinensis are used in Traditional Chinese Medicine and serve as a source for the isoquinoline alkaloids berberine , palmatine, and coptisine among others… Coptis chinensis is one of the 50 fundamental herbs used in traditional Chinese medicine… Because of the strong coloring quality of berberine, it has been traditionally used as a dye, especially for wool and other fibers.“
https://en.wikipedia.org/wiki/Coptis_chinensis

„Coptis chinensis Franch („Oung Ney“ in Thai; Ranunculaceae) Rhizome of C.chinensis has been used in traditional Chinese medicine for clearing away heat and depriving dampness for treatment of diarrhea, dysentery and jaundice, and purging the ethnic fire and clearing away toxic material for the cases of seasonal febrile diseases, carbuncle, sore throat. The major active ingredient of the herb, berberine, is an isoquinoline derivative alkaloid and has many pharmacological effects.“
[Aroonrerk, Nuntana, and Narisa Kamkaen. „Anti-inflammatory activity of Quercus infectoria, Glycyrrhiza uralensis, Kaempferia galanga and Coptis chinensis, the main components of Thai herbal remedies for aphthous ulcer.“ Journal of Health Research 23.1 (2009): 17-22] http://www.thaiscience.info/journals/Article/JHRE/10893379.pdf

1-4 Coptis chinensis var.chinensis (5-8 C.omeiensis), Flora of China