A New Glucosyl Feruloyl Quinic Acid as a Potential Marker for Roots and Rhizomes of Goldenseal, <i>Hydrastis </i><i>c</i><i>anadensis</i>

A new compound, 5-<i>O</i>-(4‘-[β-d-glucopyranosyl]-<i>trans-</i>feruloyl)quinic acid (GPFQ, <b>10</b>), is reported from the medicinal plant goldenseal (<i>Hydrastis canadensis</i>). A new HPLC method is described and used to show that GPFQ is a potential marker for goldenseal roots (1.0% w/w) and rhizomes (2.3%). GPFQ was found at much lower levels in stems (<0.1%) and could not be detected in leaves. Neochlorogenic acid (<b>9</b>), which has not previously been reported from goldenseal, and chlorogenic acid (<b>6</b>) reached their highest levels in leaves (0.9% <b>9</b> and 0.5% <b>6</b>). The main alkaloids, hydrastine (<b>1</b>) and berberine (<b>2</b>), were highest in rhizomes (2.8% <b>1</b> and 4.6% <b>2</b>), but palmatine (<b>5</b>) was not found in genuine goldenseal.