Citrus unshiu have been cultured in Jeju Island,Korea for a long time.It contains a plentiful of vitamin C and other antioxidantive pigments such as carotenoid and flavonoid.It has a wide range of flavonoid constituents,some of which,hesperidin,naringin,and polymethoxylated flavones,are lower cholesterol and down-regulate the production of promatrix metalloproteinase.