Tu Huang Lian

Tu Huang Lian is most commonly identified as Mahonia bealei (family Berberidaceae), a regional substitute for true Huang Lian (Coptis). It is an evergreen shrub 1 to 4 metres tall with stout, sparsely branched, pithy stems whose inner wood and root yield a vivid yellow pigment, indicating the presence of berberine and related isoquinoline alkaloids. The leaves are alternate, large (up to 40 centimetres long), and odd-pinnate with seven to fifteen rigid, broadly ovate, spiny-toothed leaflets reminiscent of holly. In late winter and early spring, dense erect terminal racemes of small, fragrant, lemon-yellow flowers appear, followed by waxy, blue-black, grape-like berries borne in pendent clusters. The shrub is native to thickets and woodland margins of central and southern China and is also widely planted as an ornamental.