Bioavailability and bioactivity of free ellagic acid compared to pomegranate juice

Pomegranates are an excellent source of ellagic acid (EA), ellagitannins (ETs), anthocyanins and other phytochemicals. Health benefits of pomegranate (Pom) have been mainly related to its EA and ET content. The objective of the present study was to determine EA bioavailability and bioactivity form different sources wither pure/free or in natural form (PomJ). This was a cross-over study with healthy volunteers consume one dose of EA dietary supplement (500 mg free EA) vs. one serving of PomJ (237mL, ~120 mg of EA) in random order. Our data showed that there was no difference in plasma EA concentration between PomJ and EA intake, however, urinary dimethylellagic acid glucuronide (DMEAG), normalized to creatinine, was significantly higher after consumption of PomJ compared to EA. Plasma insulin at 1hr increased after PomJ consumption compared to baseline while decreased after EA consumption compared to baseline. Plasma glucose decreased to below baseline 2 hours after consumption of PomJ but not EA. Plasma leptin was significantly decreased at 1 and 2hrs after PomJ and EA consumption. Plasma MCP1 decreased only after PomJ but not pure EA. To conclude, increase in phase II metabolism of EA and an acute suppression of plasma MCP1 were only observed after PomJ consumption suggesting that other constituents present in PomJ in addition to EA, are bioactive, and likely play a role in regulating EA phase II metabolism.