The extraction of anthocyanin from the stem and leaf of wisteria sweet potato and its comprehensive utilization of the by-product

The stem and leaf of wisteria sweet potato was used as experimental materials in this paper, the best process condition of extraction of anthocyanin and the comprehensive utilization of by -products resources were discussed. The result showed that the optimum ethanol concentration, the ratio of solid to liquid, extraction time, and extraction temperature were 95%, 1∶40, 50℃, 24h. In addition, the by-product of extracted anthocyanin also could be used, the yield of leaf protein was 7.32% , the yield of fiber was 13.02% , the content of flavone was 6.07% , a lot of nutrient substance was contained in its side product, which could be transformed into treasure, as to improve the utilization of the stem and leaf.