Douglas, James A.Follett, John M.Parmenter, Graeme A.Sansom, Catherine E.Perry, Nigel B.Littler, Ray A.2010-07-042010-07-042010Douglas, J.A., Follett, J.M., Parmenter, G.A., Sansom C.E., Perry, N.B. & Littler, R.A. (2010). Seasonal variation of biomass and bioactive alkaloid content of goldenseal, Hydrastis Canadensis. Fitoterapia, published online on 13 June 2010.https://hdl.handle.net/10289/4087Seasonal variations in biomass and alkaloid contents of goldenseal (Hydrastis canadensis) were investigated. Five-year-old plants gave 5× the yield of roots and rhizomes of two-year-old plants, and summer growth gave significant increases in root biomass but not rhizomes. Berberine contents of roots plus rhizomes did not vary significantly and were > 3.4% in all samples. Hydrastine contents of 5 y roots plus rhizomes showed significant seasonal variation. These variations were due to significant changes in the hydrastine contents of the roots (1.3–1.9%), but not the rhizomes (2.2–2.8%). Goldenseal leaves plus stems had lower contents of hydrastine (0.4–0.8%) and berberine (1.0–1.5%).enHydrastis canadensisalkaloidsplant partsharvest timeberberinehydrastineJournal Article10.1016/j.fitote.2010.06.006