First accurate profiling of antioxidant anthocyanins and flavonols of Tibouchina urvilleana and Tibouchina mollis edible flowers aided by fractionation with Amberlite XAD-7.

A purification and fractionation process of the edible flowers of Tibouchina mollisand Tibouchinaurvilleana followed by the first attempt to the anthocyanin and flavonol characterisation and identification by UHPLC-DAD-ESI-MS were developed. T. urvilleana exhibited a higher monomeric anthocyanin content, mainly due to the presence of the 3-O-(6′-p-coumaroyl)-glucoside derivatives of malvidin and petunidin. Quercetin-3-O-hexoside was the major flavonol identified in T. urvilleana, and the lack of myricetin derivatives was also exhibited. The anthocyanin and flavonol profile of T. mollis was more miscellaneous, characterised by the occurrence of cyanidin-3-O-glucoside followed by the 3-O-(6′-p-coumaroyl)-glucoside and 3-O-glucoside derivatives of malvidin and petunidin as anthocyanins, and myricetin, quercetin, and 3-O-hexosides of kaempferol and quercetin as flavonol compounds. Therefore, the anthocyanin and flavonol profile, through a process based on purification and fractionation, could be a useful tool...