Anthocyanin analyses of Vaccinium fruit dietary supplements

Abstract

Vaccinium fruit ingredients within dietary supplements were identified by comparisons with anthocyanin analyses of known Vaccinium profiles (demonstration of anthocyanin fingerprinting). Available Vaccinium supplements were purchased and analyzed, their anthocyanin profiles (based on high-performance liquid chromatography [HPLC] separation) indicated if products’ fruit origin listings were authentic. Over 30% of the Vaccinium fruit (cranberry, lingonberry, bilberry, and blueberry; 14 of 45) products available as dietary supplements did not contain the fruit listed as ingredients. Six supplements contained no anthocyanins. Five others had contents differing from labeled fruit (e.g., bilberry capsules containing Andean blueberry fruit). Of the samples that did contain the specified fruit (n = 27), anthocyanin content ranged from 0.04 to 14.37 mg per capsule, tablet, or teaspoon (5 g). Approaches to utilizing anthocyanins in assessment of sample authenticity, and a discussion of the challenges with anthocyanin profiles in quality control are both presented.