Antioxidant Properties And Phytochemical Composition Of Shaanxi-Grown Pomegranate Seeds

Pomegranate (Punica granatum) has been planted in China for more than 2000 years. Today, pomegranate trees are widely cultivated in China, especially in Shaanxi province, for their good reputation of nutritional and commercial value.Pomegranate seed as a byproduct of pomegranate processing is about 20% (w/w) of the whole fruit. Recent studies found that pomegranate seed may have the potential to be a good source of nutrients and antioxidants. It has been suggested that dietary supplementation with pomegranate seed may prevent DNA damage, reduce risk of cancer and alleviate menopausal symptoms. In this study, four cultivars of Shaanxi-grown pomegranate seeds were investigated for their phytochemical content and antioxidant properties.Pomegranate seed oils were analyzed for their fatty acid profiles, tocopherols, and carotenoids. The defatted flours were extracted by 50% acetone and 80% methanol, and evaluated for levels of phenolics, flavonoids, proanthocyanidins and DPPH? scavenging capacity, ABTS?+ scavenging capacity and ferric ion reducing capability. Total lipids of pomegranate seeds were 114.2 to 147.9 mg/g based on dry seed weight. Pomegranate seed oil was rich in punicic acid (73.5~78.8 g/100 g oil) and total tocopherols (5.3~12.0μmol/g). 50% acetone and 80% methanol were appropriate solvents for extraction of total phenolic and total flavonoid, respectively. Four cultivars were significantly different in levels of phenolics, flavonoids, proanthocyanidins and their antioxidant properties (P < 0.05), generally following an order: Suanshiliu > Tianhongdan > Sanbaitian≈Jingpitian.This study will assist in the cultivar selection of the above pomegranate seeds for commercial production to meet market demand.