Optimization of subcritical water extraction of phenolic compounds from Ziziphus jujuba using response surface methodology: evaluation of thermal stability and antioxidant activity

Abstract Background The jujube is mainly grown in the subtropical and tropical regions of Asia. Due to owning bioactive compounds such as polyphenols, it was considered medicinal nutritional plant traditional medicine. This study aimed extract phenolic from Ziziphus jujuba using subcritical water (SCW) process. possible combinations temperature, time, fruit-to-solvent ratio were investigated response surface methodology. Results total (TPC) radical scavenging capacity (RSC) 975.94 mg/g 53.98%, respectively, recovered at optimum extraction conditions (170 °C, 74.49 min, 1:5.29). obtained SCW put under thermal treatments including low temperature long high short cooking, baking, sterilization. results showed after amount TPC, RSC, absorbance 420 nm increased. quantity gallic acid, chlorogenic p -coumaric ferulic rutin increased significantly. efficiency retarding lipid oxidation bulk oil O/W emulsion model 50 °C for 10 days. After days, peroxide value (1.1 meq O 2 /kg) containing lower than (2.2 /kg). Conclusion extracted seem have good antioxidant activity well stability food or drug industries.