Hydroquinone

plant extracts such as Mitracarpus scaber (madder) extract, Uva ursi (bearberry) extract, Morus bombycis (mulberry), Morus alba (white mulberry), and Broussonetia papyrifera (paper mulberry) touted as being natural skin lightening agents actually break down into hydroquinone when absorbed into skin. and it has been found to be most effective in resolving pigmentary problems.  Hydroquinone is a lightener used in many topical skin products to lighten discoloration, age spots, freckles and melasma. This ingredient works by suppressing the formation of melanin, the pigment that causes skin to darken.