Abstract: Biological activities of total polyphenol extracts from pomegranate peel grown in Xinjiang were studied. DPPH radical-scavenging method and agar dilution method were employed to evaluate antioxidant and antibacterial activities, respectively. MTT assay was used to evaluate anti-tumor activity. All four extracts exhibited strong DPPH free radical scavenging activity, and the DPPH free radical scavenging activity of two purified extracts was superior to that of the crude extracts. The purified extracts had an obvious inhibitory effect against clinical common pathogenic bacteria, especially some drug-resistant bacteria and an effective anti-tumor activity. Therefore, total polyphenol extracts with high purity from pomegranate peel grown in Xinjiang have effective antioxidant, antibacterial and anti-tumor activities.

Key words: Punica granatum L., total polyphenols, antioxidant activity, antibacterial activity, anti-tumor activity