|
A new clinical trial has demonstrated that a pomegranate (Punica granatum) whole fruit extract can deliver absorbable ellagic acid (EA, a compound with antioxidant and anti-cancer properties found in various plants) and other antioxidant metabolites, and produce antioxidant effects.1 The study was conducted on a pomegranate extract standardized to punicalagins (PUN, the major ellagitannins found in pomegranate juice) (POMELLA® extract, Verdure Sciences, Noblesville, IN). The antioxidant activity was measured by plasma ORAC (oxygen radical absorbance capacity).
In this pharmacokinetic trial, conducted at the University of Florida, 11 healthy men and women began with a 3-day washout from consumption of polyphenol-rich foods (such as tea, wines, berry fruits, etc.), then consumed 2 capsules containing 400 mg each of the pomegranate extract. Blood was drawn from participants before, after, and at multiple points during the trial day. (Pharmacokinetic trials measure the absorption, metabolism, half-life, and/or excretion of nutritionally and pharmacologically active agents in foods, dietary supplements or drugs.)
EA and metabolites known to hydrolyze from PUN were detected in plasma after consumption of the pomegranate extract.2 The mean maximum concentration (Cmax) of EA was 33.8 ng/mL at 1 hour. (The EA Cmax was comparable to that observed in the recent human pharmacokinetic study on the metabolism of concentrated pomegranate juice in humans.3)
The antioxidant capacity of plasma was significantly increased in study participants by an overall average of 31.8% at 30 minutes after consumption. A second peak in antioxidant capacity of 31.7% was observed after 6 hours. The results were characterized by intersubject variability.
The study’s investigators wrote that the results “demonstrated bioavailability for EA and its derivatives after consumption of a pomegranate extract high in ellagitannins, indicating its potential in the promotion of health.” They also noted that a more comprehensive study using a placebo group would be required to confirm the antioxidant effects of the pomegranate extract.
-Courtney Cavaliere
References
1. Mertens-Talcott SU, Jilma-Stohlawetz P, Rios J, Hingorani L, Derendorf H. Absorption, metabolism, and antioxidant effects of pomegranate (Punica granatum L.) polyphenols after ingestion of a standardized extract in healthy human volunteers. Journal of Agricultural and Food Chemistry. 2006;54(23):8956-8961.
2. Larrosa M, Tomas-Barberan FA, Espin JC. The dietary hydrolysable tannin punicalagin releases ellagic acid that induces apoptosis in human colon adenocarcinoma Caco-2 cells by using the mitochondrial pathway. J Nutr Biochem. 2006 Sep;17(9):611-25.
3. Seeram NP, Henning SM, Zhang Y, Suchard M, Li Z, Heber D. Pomegranate juice ellagitannin metabolites are present in human plasma and some persist in urine for up to 48 hours. J Nutr. 2006 Oct;136(10):2481-5.
|