Abstract: The black sweet corn was used as raw material in this experiment to extract pigment,the effect of different factorson extraction of pigment with orthogonal design test was investigated.The results showed that among the tested factors acidityis the main influenced factors,and the optimum condition was that the extractive reagent was mixture in which 70% alcohol and0.1mol/L HCl (pH=2), the weight of mixture was 5 times as large as that of the black corn,the black sweet was extracted two timesat 70℃,each step for 120min.Purified by silica gel column chromatography, the purity of product is higher.

Key words: black sweet corn, pigment, extraction, purification