Lingonberries (Vaccinium vitis-idaea L) and blueberries (Vaccinium corymbosum) contain discrete epicatechin anthocyanin derivatives linked by ethyl bridges.

BACKGROUND:
Lingonberries have been associated with a range of potential bioactivities related to their polyphenol content and composition, in particular anthocyanin and proanthocyanidin derivatives.
OBJECTIVES:
The objective of this study was to examine the anthocyanin composition of extracts of lingonberry and related Vaccinium berries with respect to previously unidentified anthocyanin-like components.
METHODS:
Extracts were prepared from lingonberries, blueberries and a commercial cranberry juice product and examined by liquid chromatography mass spectroscopic techniques (LCMSn) before and after various fractionation steps.
RESULTS:
A range of discrete anthocyanin derivatives ethyl linked to (epi)catechin units were identified in lingonberry extracts using LC-MSn methods. Analogous derivatives were detected in similar blueberry extracts, and confirmed in cranberry juices.
CONCLUSIONS:
Through a combination of fractionation techniques and LCMSn analysis, this paper provides the first evidence that anthocyanin-epicatechin derivatives linked by ethyl bridges are present in lingonberries and in blueberries. These discrete components may be the smallest in a series of proanthocyanidin derivatives with terminal anthocyanins linked through ethyl groups which have previously been inferred in cranberries using mass spectrometric techniques.