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

Abstract

Summary A purification and fractionation process of the edible flowers of Tibouchina mollis and Tibouchina urvilleana 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 kaemperol and quercetin as flavonol compounds. Therefore, the anthocyanin and flavonol profile, through a process based on purification and fractionation, could be a useful tool to ensure the authenticity of the Tibouchina. Furthermore, the purification process made the antioxidant activity increase, which is greatly correlated to the reduction capacity.

The influence of sonication times on bioactive compounds, antioxidant activity values, and phenolic compounds of immature and mature types linden blossoms

“…Ramírez‐Bolanos et al (2021) reported that dried banana flower and dried banana pseudostem may have the potential to be used as food ingredients due to the phenolic profile of dried banana flower and its byproducts. Solarte et al (2022) determined that a deficiency of myricetin derivatives was also detected in Tibouchina urvilleana . The anthocyanin and flavonol profile of Tibouchina mollis was more diverse, with the formation of cyanidin‐3‐O‐glucoside followed by 3‐O‐(6′‐p‐coumaroyl)‐glucoside and 3‐O‐glucoside derivatives of malvidin and petunidin as anthocyanins.…”

“…The anthocyanin and flavonol profile of Tibouchina mollis was more diverse, with the formation of cyanidin‐3‐O‐glucoside followed by 3‐O‐(6′‐p‐coumaroyl)‐glucoside and 3‐O‐glucoside derivatives of malvidin and petunidin as anthocyanins. As flavonol compounds, myricetin, quercetin and kaemperol, and quercetin 3‐O‐hexosides were characterized (Solarte et al, 2022). Grajeda‐Iglesias et al (2022) reported that the first lypophilization of ellagitannins from pomegranate peel was carried out, and based on previous studies, polyphenols (an anthocyanin and a phenolic acid) extracted from hibiscus flowers were successfully lypophilized.…”

Semisynthesis of Betaxanthins from Purified Betacyanin of Opuntia dillenii sp.: Color Stability and Antiradical Capacity

“…Betalains were eluted from the column with three volumes of water type II (PE2), and then the betalain extract (PE2) was lyophilized (Figure 7). The colorless polyphenols, together with sugars and organic acids, from PE1 that were retained in the resin were eluted with methanol/acid (19:1) to be discarded [34].…”

“…Subsequently, 30 µL of betaxanthin was added to 3 mL of the diluted solution of ABTS •+ . After stirring for 1 min and waiting for 6 min, the absorbance at 734 nm was spectrophotometrically measured (UV-Vis Pharo, Merck, Darmstadt, Germany) [34,36]. Results were obtained by interpolation of the absorbance in the trolox calibration curve (0.5-2.5 µM).…”