test method:hplc. molecular formula: c15h12o7, molecular weight: 304.25 . physics properties:without color needle crystal (50%ethanol),melting point 240-2400c.lightly soluble in the ethanol ,acetic acid ,boil water, slightly soluble in cold water ,hardly soluble in the chloroform.the light yellow powder’s melting point is 208-210’c. pharmacology function: background: overproduction of cholesterol and apolipoprotein b (apob) by the human liver is an important contributor to the development of coronary artery disease (cad). while common factors have been investigated, the effects of plant flavonoids on cholesterol and apob production remains to be addressed. objective and method: using a human hepatoma cell-line, hepg2 cells, as the model system, a plant flavonoid, taxifolin, will be studied for its effect on cholesterol and apob production. interest in taxifolin as a hypocholesterolemic agent is derived from its structural homology to silybin, a known hmg coa reductase inhibitor. hypothesis: will taxifolin-treated hepatocytes decrease the production of cholesterol and the atherogenic apob particle. clinical significance: it is hope that this research study may provide a better understanding on how plant flavonoids reduce cholesterol and apob production which could contribute to better clinical management of patients with cad.