Maria Maiz 1, Dennis P. Cladis 1, Pamela J. Lachcik 1, Elsa M. Janle 1, Mary Ann Lila 2, Mario G. Ferruzzi 1 and Connie M. Weaver 1 (2016). Acute Bioavailability of (Poly)phenolic Content of Different Varieties of Vaccinium spp. in Ovariectomized Rats. The FAESB Journal, 30(1).
1. Nutrition Science, Purdue University, West Lafayette, IN
2. Food, Bioprocessing, and Nutrition Sciences, North Carolina State University, Kannapolis, NC
Blueberries have a wide range of health promoting activities due to their high levels of (poly)phenols, including anthocyanins, flavonols, and phenolic acids. However, there are 1200 varieties of blueberries and their phenolic content varies greatly. Thus, the goal of this investigation was to characterize the total phenolic content in 9 varieties of Vaccinium spp. berries as well as determine whether there is a difference in their bioavailability after an acute dose in ovariectomized rats.
Nine varieties of berries (Ira, Legacy, Montgomery, Onslow, SHF2B1-21:3, Sampson, Cranberry, Bilberry and two Wild blueberry composites from the years 2012 and 2013) were selected based on PCA analysis of their anthocyanidin content and sourced from the North Carolina State University Blueberry Genome Repository. Berries were freeze-dried and phenolics were extracted with 2% formic acid 80:20 MeOH:H2O solvent and purified using solid phase extraction (SPE). Total phenolic content was determined via the Folin-Ciocalteu assay and individual phenolics where identified and quantified by HPLC-MS.
For the bioavailability study, eighty-four Sprague-Dawley rats were given an acute dose of 25mg of total phenolics/kg of body weight by gavage as a freeze-dried blueberry powder solution (aq.) and serial blood draws and urine were collected over 8 hours. Plasma samples were extracted by SPE and analyzed by HPLC-MS/MS for anthocyanin glycosides and flavonoid metabolites. Pharmacokinetic parameters (AUC, Cmax, and Tmax) were determined.
Bilberry and Wild blueberry composite 2013 have a significantly higher total phenolic content than the other varieties, while Cranberry and Sampson were the least concentrated. Montgomery and Ira varieties had the highest bioavailability for Me-Quercetin-glc and Me-Myricetin-glc metabolites, respectively, by one-way ANOVA (p < 0.05). The flavan-3-ols, catechin-glucuronide (glc), epicatechin-glc and their respective methylated metabolites, were not significantly different between varieties of blueberries.
Total (poly)phenolic content and bioavailability of individual phenolics varied widely among blueberry varieties. This information will serve to inform future investigations in cells, animals, and clinical trials.