Standardised pomegranate extracts lead to increased levels of bioactive compounds in the blood and boost antioxidant levels, says new research that could see the extracts start to rival the juice for boosting health.
Consumption of pomegranate juice has been on the rise, particularly in the UK where sales have rocketed in the last year thanks to media coverage of the antioxidant-rich fruit that has commonly been linked to improved heart health, as well as claims that pomegranate could protect against prostate cancer and slows cartilage loss in arthritis.
While there is a growing number of trials reporting benefits of pomegranate juice, the researchers behind the new study, led by Susanne Mertens-Talcott from the University of Florida state: "No human intervention studies have been conducted with an oral administration of a pomegranate extract standardized to punicalagins."
Punicalagins are believed to be the main active components responsible for the fruit's health-promoting properties.
"Due to the health benefits now attributed to pomegranate consumption and the rising popularity of pomegranate botanical supplements, human intervention studies using pomegranate extract supplements are crucial for determining the efficacy of pomegranate extracts in the prevention of chronic diseases and establishing science-based dosing recommendations," said the authors.
"The current study if the first to investigate pharmacokinetic parameters, absorption, metabolism, and ex vivo biological activities of a whole-fruit extract of pomegranate standardized to punicalagins in healthy human volunteers."
Writing in the Journal of Agricultural and Food Chemistry, the researchers report that blood levels of the metabolites of punicalagins, most notably ellagic acid and its derivatives in 11 healthy men and women (average age 37.6, average BMI 32.6), showing the extracts were absorbed efficiently in gastro-intestinal tract.
Mertens-Talcott go on to report that blood antioxidant levels, measured using the oxygen radical absorbance capacity (ORAC) assay, increased by 32 per cent after consumption of the extracts (Pomella, 800 mg of extract giving 330.4 punicalagins), with levels sustained over eight hours.
"Overall, this exploratory study with pomegranate extract demonstrated bioavailability for EA and its derivatives after consumption of a pomegranate extract high in ellagitannins, indicating its potential in the promotion of health," wrote the researchers.
This initial study will undoubtedly be followed by larger and longer human interventions to further investigate the potential of the pomegranate extract to promote health.
Source: Journal of Agricultural and Food Chemistry
Published on-line ASAP article, doi: 10.1021/jf061674h
"Absorption, metabolism, and antioxidant effects of pomegranate (Punica granatum L.) polyphenols after ingestion of a standardized extract in healthy human volunteers"
Authors: S.U. Mertens-Talcott, P. Jilma-Stohlawetz, J. Rios, L. Hingorani, H. Derendorf