Submitted to: Journal of Functional Foods
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 16, 2012
Publication Date: February 4, 2013
Citation: Lee, J. 2013. Proanthocyanidin A2 purification and levels found in American cranberry (Vaccinium macrocarpon Ait.) products. Journal of Functional Foods. 5:144-153.
Interpretive Summary: Cranberry products are popular for their tart flavor and for their potential healthfulness. These products may also prevent or provide a remedy for urinary tract infections (UTIs). However, research results in this area are unclear, possibly due to the sample preparation method used by researchers. In this study, we examined five commonly used cranberry sample purification methods prior to phytochemical analysis. The current available commercial cranberry products were eleven-fold different in proanthocyanidin content, the compound that might possibly prevent UTIs. During this investigation, a cranberry juice cocktail product was discovered that contained a red pigment not originating from cranberry fruit.
In this study, five common proanthocyanidin purification techniques were evaluated prior to phloroglucinolysis, followed by HPLC analysis. An optimized purification method was then used to identify and quantify the proanthocyanidins (extension and terminal units of epigallocatechin, catechin, epicatechin, A type trimer, and A type dimer) of commercially available cranberry products (juices, concentrates, tablets, and capsules; n=17). Two size exclusion beads (Toyopearl 4 TSK HW-40C and Sephadex LH-20) were found suitable for proanthocyanidin purification, though proanthocyanidin extension and terminal unit composition was contingent upon the cleanup procedure utilized. These data illustrate that purification methods require consideration prior to conducting any cranberry proanthocyanidin analyses, and have to be accounted for when comparing values between studies. Total proanthocyanidin levels ranged from 11.7 (juice) to 436.4 (tablet) mg/100 mL or 100 g values obtained from Sephadex LH-20 purification, while total anthocyanin levels ranged from 0.54 (juice) to 98.00 (tablet) mg/100 mL or 100 g.