In Traditional Chinese Medicine (TCM) color as well as configuration of an herb suggests the therapeutic corresponding action. Yellow herbs tend to affect the Stomach and Spleen (here referring to systems not specific organs), and the adverse climate of dampness. Bitter Yellow roots are said to clear Damp Heat through eliminative action. It is no surprise to find that it has been used to promote a healthy digestive environment, as well as a healthy microbial environment in cases where immune support is indicated. Berberine alkaloids in Coptis have been researched for their influence on microbes in animal tissues.