Enhanced NMR-based profiling of polyphenols in commercially available grape juices using solid-phase extraction.

Grapes and related products, such as juices, and in particular, their polyphenols, have previously been associated with many health benefits, such as protection against cardiovascular disease. Within grapes, a large range of structurally diverse polyphenols can be present, and their characterisation stands as a challenge. (1)H NMR spectroscopy in principle would provide a rapid, nondestructive and straightforward method for profiling of polyphenols.

Nutrimetabolomics: development of a bio-identification toolbox to determine the bioactive compounds in grape juice.

Background: Grape juice and related products have previously been associated with many health benefits, such as protection against cardiovascular disease. Current consensus is that the polyphenols are the likely bioactive species in these products.

Results: Extracts of commercially available grape juices exhibited biological antioxidant activities ranging from 19.