Exploration of pharmacological properties of pomegranate and enrichment of antioxidants in pomegranate juice

Abstract

Pomegranate (Punica granatum L.) is an important plant of tropical and subtropical regions of the world. Pomegranate rind/peel contains substantial amounts of polyphenols such as ellagic tannins, ellagic acid and gallic acid. Phenolic components extracted from pomegranate have shown to possess antioxidant property. However, the role of these phenolic components for prevention of diabetic complication and development of Advanced Glycation End Products (AGEs) has not yet been established. Most of the studies on pharmacological properties of pomegranate peel are restricted towards the effect of low molecular weight phenolics. In the present investigation, a polysaccharide fraction from pomegranate was isolated and its efficacy in reducing oxidative stress and diabetic complications was evaluated. The effect of molecular weight of the polysaccharides towards their bioactive potential was also studied. In the present study, the effect of a purified phenolic fraction (PLP) isolated from pomegranate peel in reducing alloxan induced diabetes and maintaining the serum antioxidant level was investigated. It was observed that PLP is a strong inhibitor of alloxan induced diabetes owing to its antioxidant activity. The action of PLP in reducing the serum glucose level in alloxan induced mice coupled with its α-amylase inhibition activity speaks about its possible benefit as an anti-diabetic agent. PLP was found to be a mixture of gallic acid and ellagic acid. The protective action of the polysaccharide fractions isolated from pomegranate was also elucidated against free radical mediated diseases. It was found that polysaccharide fractions are strong inhibitors of the AGEs which contribute to different diabetic complications. This study also indicated the effect of mass and composition of polysaccharides for its antioxidant activity. The antioxidant value was found to increase with increase in mass of the polysaccharide.