The impact of the growth environment on the production of health-promoting phytochemicals in cranberry fruit (Vaccinium macrocarpon Aiton) is not well established despite increased production worldwide. We investigated the secondary metabolite composition among the cranberry fruit of nine cultivars produced in two major coastal North American growing regions that differ in climate. Using 1H NOESY NMR to generate metabolic fingerprints, principal component analysis revealed variation between the two regions and identified likely contributing metabolites. Triterpenoids ursolic and oleanolic acid, as well as citric and malic acids, were quantified using 1H qNMR, and anthocyanins and flavonols were determined by HPLC-DAD. Total proanthocyanidins (PACs), total soluble phenolics, and DPPH free-radical scavenging antioxidant activity were also evaluated. Across all cultivars, anthocyanins, flavonols, and total phenolic content were significantly higher in West Coast fruit than East Coast fruit, correlating with a regional trend of higher antioxidant activity in fruit grown on the West Coast. The opposite trend was observed for triterpenoids and organic acids, which were significantly higher across cultivars in East Coast fruit. These trends persisted over two growing seasons. The study demonstrates that climate plays an important role in the production of antioxidant and anti-inflammatory phytochemicals in cranberry plants.
Cranberry pomace is a rich, but underutilized source of polyphenols and other bioactive compounds. This study assessed the efficacy of six solvent mixtures comprising combinations of ethanol, methanol, acetone, formic acid, and water for extraction of antioxidants from pomace. The antioxidant activity and total phenolic content of the cranberry pomace extracts were evaluated using DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS•+(2,2′-azinobis(3-ethylbenzthiazolin-6-sulfonic acid), FRAP (ferric reducing power), and Folin–Ciocâlteu assays, the total proanthocyanidin content was estimated using the dimethylaminocinnamaldehyde (DMAC) method, and individual polyphenolics and triterpenoids were determined using HPLC-DAD and UPLC-MS. Extracts exhibited a broad range of total phenolic content at 21–166 mg gallic acid equivalents (GAE)/g extract), total PACs (proanthocyanidins) at 6–240 mg PAC equivalents/g extract, anthocyanins at 0.42–1.77 mg/g extract, flavonols at 4.09–11.7 mg/g extract, and triterpenoids at 85.6–287 mg/g extract. Antioxidant activities varied widely and correlated positively with all polyphenol categories, but negatively with triterpenoids. An extract produced using an acetone, methanol, water and formic acid mixture demonstrated optimal antioxidant properties, total phenolic content, and total proanthocyanidin content and was further characterized. Our findings emphasize the importance of solvent selection for targeted bioactive constituents and highlight cranberry pomace as a promising source of antioxidants.