Quantification of punicalagins in commercial preparations and pomegranate cultivars, by liquid chromatography-mass spectrometry.

Background: Pomegranate (Punica granatum L.) - a delicious fruit once used in Ayurvedic medicine - is now largely known for the antioxidant properties of its juice, which has also been considered to have health benefits against diseases such as cancer and cardiovascular diseases. These beneficial effects are associated with the fruit's high content of polyphenolic compounds. High demand and lower production levels drive pomegranate prices up, which leads to the possibility of pomegranate products being adulterated, diluted or substituted. To ensure the presence of pomegranate in various preparations labeled as containing pomegranate, a simple method was developed to screen and quantify the specific punicalagins by mass spectrometry.

Results: The present method was used to analyze several pure and mixed beverages from the US market, and also to quantify punicalagins in the juice of 14 pomegranate cultivars. Punicalagins were detected in all cultivars, with higher concentrations in whole fruit juices compared with aril juices. Amongst the 20 commercial beverages, punicalagins were not detected in four preparations.

Conclusion: The liquid chromatographic-mass spectrometric method presented herein enables an easy and rapid quantification of the specific punicalagins. The latter was detected in all cultivar samples, thus supporting that punicalagin is a suitable marker of these 14 pomegranate cultivars in commercial juices. Absence of the specific marker in four commercial preparations shows the necessity of having simple and rapid methods to evaluate the presence of pomegranate in preparations. © 2019 Society of Chemical Industry.