Cortex phellodendri (Phellodendron Chinense) is a berberis of the family rutaceae, mainly produced in Hubei, northwestern Hunan and eastern Sichuan. Cortex phellodendri uses bark as medicine, containing berberine, cortex phellodendri, magnolia alkaloid and other components, can be antibacterial, hypotensive, aid digestion, etc. Berberine hydrochloride is an isoquinoline alkaloid, molecular formula [C20H18NO4]+, also known as berberine. It is found in many plants of 4 families and 10 genera, such as berberidae. Berberine can precipitate yellow needle crystals from diethyl ether. To dysenteric bacili, Escherichia coli, pneumococcus, aureus, streptococcus, typhoid bacili and amoeba have inhibitory effect. It is mainly used for intestinal infection and dysentery. It is also found that this product has the effect of anti-arrhythmia.