BACKGROUND: The objective of this study was to validate an improved 4-dimethylaminocinnamaldehyde (DMAC) colorimetric method using a commercially available standard (procyanidin A2), for the standard method for quantification of proanthocyanidins (PACs) in cranberry powders, in order to establish dosage guidelines for the uropathogenic bacterial anti-adhesion effect of cranberry. RESULTS: Commercially available cranberry samples were obtained (five from U.S. sources and six from European sources) for PAC quantification in five different analytical laboratories. Each laboratory extracted and analyzed the samples using the improved DMAC method. Within-laboratory variation (mean +/- SD) was 4.1 +/- 1.7% RSD (range, 2.3-6.1% RSD) and the between laboratory variability was 16.9 +/- 8.5% RSD (range, 8-32% RSD). For comparative purposes, the cranberry samples were alternatively quantified using weights of extracted PACs (gravimetric). The correlation coefficient between the two methods was 0.989. CONCLUSION: This improved DMAC method provides a simple, robust and relatively specific spectrophotometric assay for total PACs in cranberry samples using commercially available procyanidin A2 dimer as a standard. DMAC is most useful within a given type of food such as cranberries, but may not be appropriate for comparing concentrations across different food types, particularly in those cases where large differences exist among the relative amounts of each oligomer and polymer.
BACKGROUND: The objective of this study was to validate an improved 4-dimethylaminocinnamaldehyde (DMAC) colorimetric method using a commercially available standard (procyanidin A2), for the standard method for quantification of proanthocyanidins (PACs) in cranberry powders, in order to establish dosage guidelines for the uropathogenic bacterial anti-adhesion effect of cranberry. RESULTS: Commercially available cranberry samples were obtained (five from U.S. sources and six from European sources) for PAC quantification in five different analytical laboratories. Each laboratory extracted and analyzed the samples using the improved DMAC method. Within-laboratory variation (mean +/- SD) was 4.1 +/- 1.7% RSD (range, 2.3-6.1% RSD) and the between laboratory variability was 16.9 +/- 8.5% RSD (range, 8-32% RSD). For comparative purposes, the cranberry samples were alternatively quantified using weights of extracted PACs (gravimetric). The correlation coefficient between the two methods was 0.989. CONCLUSION: This improved DMAC method provides a simple, robust and relatively specific spectrophotometric assay for total PACs in cranberry samples using commercially available procyanidin A2 dimer as a standard. DMAC is most useful within a given type of food such as cranberries, but may not be appropriate for comparing concentrations across different food types, particularly in those cases where large differences exist among the relative amounts of each oligomer and polymer.
Authors: Diana E Roopchand; Christian G Krueger; Kristin Moskal; Bertold Fridlender; Mary Ann Lila; Ilya Raskin Journal: Food Chem Date: 2013-06-21 Impact factor: 7.514
Authors: Li Zhang; Rachel N Carmody; Hetal M Kalariya; Rocio M Duran; Kristin Moskal; Alexander Poulev; Peter Kuhn; Kevin M Tveter; Peter J Turnbaugh; Ilya Raskin; Diana E Roopchand Journal: J Nutr Biochem Date: 2018-02-15 Impact factor: 6.048
Authors: Diana E Roopchand; Peter Kuhn; Alexander Poulev; Andrew Oren; Mary Ann Lila; Bertold Fridlender; Ilya Raskin Journal: J Agric Food Chem Date: 2012-04-16 Impact factor: 5.279
Authors: Manisha Juthani-Mehta; Peter H Van Ness; Luann Bianco; Andrea Rink; Sabina Rubeck; Sandra Ginter; Stephanie Argraves; Peter Charpentier; Denise Acampora; Mark Trentalange; Vincent Quagliarello; Peter Peduzzi Journal: JAMA Date: 2016-11-08 Impact factor: 56.272
Authors: Diana M Cheng; Peter Kuhn; Alexander Poulev; Leonel E Rojo; Mary Ann Lila; Ilya Raskin Journal: Food Chem Date: 2012-07-14 Impact factor: 7.514