ABSTRACT Direct‐infusion ESI/IT‐MS/MS was previously employed to characterize grape anthocyanins that share the same nominal mass but differ in elemental composition. Subsequently, Q‐TOF coupled with LC‐Chip enabled the complete anthocyanin fingerprint of a single sample to be obtained in under 5 min. In this study, a comprehensive UHPLC/Q‐TOF investigation of anthocyanins in three red‐berry fruits (blueberry, raspberry, and two fungal‐resistant red grape varieties) was performed. In total, 35 anthocyanins were identified. Only two were found in all three fruits, Cy and Pn 3‐ O ‐hexosides. The grape berries exhibit high levels of diglucosides, while only raspberries contain Pg derivatives and several di‐ and trisaccharide anthocyanins. Blueberry uniquely accumulated Pn‐malonylhexoside and arabinosyl anthocyanins, and a difference between the two species was found, as cv Biloxi (southern highbush) contained acetyl‐ and p ‐coumaroyl glucosides not found in cv Titan (rabbiteye), alongside a preponderance of B‐ring tri‐substituted anthocyanins. Additionally, in blueberry two isobaric anthocyanins (Pn‐hexoside and Mv‐arabinoside, MF C 22 H 23 O 11 ) were characterized. Sophoroside and rutinoside anthocyanins were found only in the raspberry, where Pn‐hexosyl‐rutinoside, Cy‐3‐hexosyl‐sophoroside, and a Cy‐rutinoside isomer were characterized for the first time. Findings of the study increase the knowledge on these varieties as potential sources of nutraceuticals and natural colorants, also expanding the HR‐MS/MS dataset beneficial for their characterization in other fruit varieties.
Rosso et al. (Wed,) studied this question.