Extraction of bioactive compounds of Persian Golnar (punica pranatum) using ohmic, ultrasound and perculation methods

Herbal bioactive compounds are secondary metabolites of plants that are produced in response to environmental stress and to protect the plant against harsh conditions. These compounds have both health effects on humans and also have preservative effects in food products. The conditions for extracting active compounds have a significant effect on their functional activities, and conventional and new methods have been used to extract bioactive compounds from plants. The aim of this study was to compare the extraction methods of bioactive compounds of Persian Golnar extract (PGE). In this research three methods of ohmic (temperatures of 45 °C and 60 °C for 40 and 60 min), ultrasonic (temperatures of 40 °C, 50 °C and 60 °C for 20 and 40 min) and perculation (for 24, 48 and 72 h) were used to prepare PGE, and the best extract was selected based on the extraction yield, total phenol content (TPC), total anthocyanin content (TAC) and antioxidant activity (DPPH radical scavenging). The results showed that there was no significant difference between the extraction yields of all three methods (p>0.05). The ohmic method had the same TPC as the ultrasonic method, but showed a higher TAC and antioxidant activity and was chosen as the best method. The optimal treatment in this stage included ohmic method, 60 °C and 40 min, and the extract obtained under these conditions contained 109.74 mg GAE/g of TPC, 373.26 mg/g of TAC and 81.11% antioxidant activity.