Profiling the phenolic acids, flavonoids and tannins in skunk currants (Ribes glandulosum) of Northern Québec, Canada

Abstract

BACKGROUND: Skunk currant is widely dispersed across North America and a feature of some traditional North American indigenous diets. Whereas many wild and cultivated berries have attracting interest related to their antioxidant phenolic metabolites and putative health benefits in humans, very few data are available concerning skunk currant phytochemistry. OBJECTIVE: Provide the first metabolic profile of skunk currant fruits with a focus on phenolic and polyphenolic compounds, owing to their emerging implications in human health. METHODS: Skunk currants were harvested in Nunavik, Québec. Flavonols, flavan-3-ols, and phenolic acids were characterized using a targeted approach with reverse-phase ultra-high pressure liquid chromatography coupled with tandem mass spectrometry. Ellagitannins and anthocyanins were measured using reverse-phase HPLC following acid hydrolysis and employing diode array detection. Proanthocyanidins and sugars were detected with normal-phase HPLC. RESULTS: A total of 11 phenolic acids and 11 flavonoids, including three cyanidins and three quercetin glycosides were identified. Both condensed (proanthocyanidins) and hydrolysable (ellagitannins) tannins were also detected at 162 mg and 75 mg per 100 g extract, respectively. The cumulative amount of detected phenolic and polyphenolic metabolites totaled 622.6 mg/100 g extract (63.4 mg/100 g berry FW). CONCLUSIONS: Skunk currant is a source of many bioactive phenolic and polyphenolic compounds. Appearing richer in phenolics than some cultivated varieties, the wild northern varieties of North America warrant additional study.