Comparative study on the chemical structure and in vitro anti-proliferative activity of anthocyanins in purple root tubers and leaves of sweet potato (Ipomoea batatas)

The structure and in vitro anti-proliferative activity of anthocyanins in the root tubers of a sweet potato variety cv Bhu Krishna and the purple leaves of a promising accession S-1467 were studied with the objectives of understanding the structure-activity relationship and to compare the leaf and tuber anthocyanins. The chemical structure of anthocyanins was determined by HR-ESI-MS analysis. FRET-based caspase sensor probe had been used to study the anti-proliferative property and analysis of cell cycle was done after staining with propidium iodide and subsequent fluorescence-activated cell sorting. Structurally the anthocyanins in root tubers were identical to those in leaves; but there was a difference in the proportion of various aglycones present in both. This has lead to distinguishable differences in the anti-proliferative activity of leaf and tuber anthocyanins to various cancer cells. All the nine anthocyanins were found in acylated forms in both tuber and leaves. However, peonidin derivatives we...