Relation of antioxidant and antifungal activity of different parts of Pomegranate (Punica granatum L.) extracts with its phenolic content

In many countries, wastage of agricultural products is due to oxidative processes and microorganisms activity in warehouses. On the other hand, many plants are the sources of compounds with high antioxidant and antifungal activities that might be used as natural preservatives. To investigate the antioxidant and antifungal properties of pomegranate, a factorial experiment based on completely randomized design with 5 replications was conducted. In this study, the effect of 3 different pomegranate parts (peel, seeds and leaf) and 2 different kind of extracts (aqueous and methanolic) with 4 concentrations (0, 500, 1000 and 1500 ppm) were investigated on 2 post-harvest fungi (Alternaria citri and Aspergillus niger). According to the results, the methanolic peel extract showed the highest inhibitory effects on the mycelia growth (IMG) and spore germination (ISG) with 47.6 and 37.7 percent respectively. Also, phenolic compounds of peel extract were 1.8 times higher than that of pomegranate leaf extract. Antioxidant capacity of peel, seeds and leaf extracts was respectively 55.3, 35.7 and 16.4%. Therefore, it seems that high antifungal and antioxidant activity of peel and seeds of pomegranate are because of high percentage of phenolic compounds in these plant parts extracts.