Optimization of Extraction Conditions for Anthocyanin Anthocyanins from Dark Maize

An orthogonal array design was applied to establish the optimum conditions of ethanol concentration,solidto-liquid ratio,solvent pH,temperature and time for increased yield and purity of anthocyanins from grains of Super Dark Maize(SDM).The results showed that maximum yield(18.71%) but minimum purity(A550nm/A275nm = 0.10) of anthocyanins were observed under the conditions of 90%,1:15(g/mL),1,80 ℃ and 15 h for ethanol concentration,solid-to-liquid ratio,pH,temperature and and time,respectively.The optimum extraction conditions to achieve maximum yield while increasing the purity of anthocyanins were 90% ethanol acidified to pH 1.5 as the extraction solvent with a solid-to-liquid ratio of 1:15,70 ℃ and 15 h.