Anthocyanins in Wild Blueberries of Quebec:  Extraction and Identification

• Published in: Journal of agricultural and food chemistry 2007-07, Vol.55 (14), p.5626-5635
• Main Authors: Nicoué, Eugéne Émile, Savard, Sylvain, Belkacemi, Khaled
• Format: Article
• Language: English
• Subjects: anthocyanins; Anthocyanins - analysis; Anthocyanins - isolation & purification; Biological and medical sciences; blueberries; Blueberry Plants - chemistry; Chromatography, High Pressure Liquid; Food industries; Fruit - chemistry; Fruit and vegetable industries; fruit composition; Fundamental and applied biological sciences. Psychology; Hydrogen-Ion Concentration; Quebec; solid phase extraction; Spectrometry, Mass, Electrospray Ionization; temperature; Vaccinium; Vaccinium angustifolium; Vaccinium myrtilloides; wild foods
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/jf0703304

Anthocyanins were extracted from a mixture of berries of Vaccinium angustifolium and Vaccinium myrtilloïdes at 7.7 °C, 26 °C, and 79 °C using ethanol alone or ethanol acidified with hydrochloric, citric, tartaric, lactic, or phosphoric acids at a solvent to solid ratio of 10. The effect of these parameters on extracted anthocyanins stability was investigated. The pH-differential and HPLC-DAD methods were used to determine anthocyanin contents. Extracted anthocyanins were purified on a C-18 solid-phase extraction cartridge and characterized by HPLC/electrospray ionization/mass spectrometry (HPLC-ESI-MS/MS). Anthocyanins were identified according to their HPLC retention times, elution order, and MS fragmentation pattern and by comparison with standards and published data. Anthocyanin extractions gave different yields depending on the type of added acid and the extraction temperature. High yields of monomeric and total anthocyanins (26.3 and 28.9 mg/g of dry matter) were obtained at 79 °C using phosphoric acid. Extraction using tartaric acid at 79 °C provided the lowest degradation index (1.05). Anthocyanins were stable and browning by polyphenol oxidase was inhibited under these conditions. Of the six common anthocyanindins, five were identified in the extracts, namely, delpinidin, cyanidin, peonidin, petunidin, and malvidin; pelargonidin was not found. In addition to well-known major anthocyanins, new anthocyanins were identified for the first time in extracts of wild blueberries from Quebec. Keywords: Vaccinium angustifolium; Vaccinium myrtilloïdes; anthocyanins; extraction; solid-phase extraction; pH differential; HPLC-DAD; degradation index; HPLC-ESI-MS/MS