Application of innovative processing methods for the extraction of bioactive compounds from saffron (Crocus sativus) petals

Extraction of bioactive ingredients from saffron petals was investigated using conventional hot water (CHW) and three green innovative processing techniques including ohmic heating assisted extraction (OHAE), ultrasound assisted extraction (UAE) and microwave assisted extraction (MAE) systems, in terms of energy consumption, yield, and physicochemical properties. Process optimization by response surface methodology showed that the optimum operating conditions were 45min-225 V, 4.25min-500 W and 40.61 min-135.3 W for OHAE, MAE, and UAE, respectively. Under the optimized conditions, extracts obtained through OHAE, MAE, UAE and CHW methods show 928, 869, 863 and 721 mg/100 g of total phenolic content (TPC), 148, 115, 130 and 101 mg/100 g of total flavonoid content (TFC) and 238, 206, 205 and 189 mg/100 g of total anthocyanin content (TAC), respectively. The IC50 values of extracts were 178, 226, 335 and 517 mu g/mL at the optimized condition of OHAE, MAE, UAE and CHW, respectively. The LC-MS profiles unveiled the presence of kaempferol derivatives and anthocyanins as main flavonols in all extracts. The extracts obtained using OHAE presented the maximum antimicrobial activity and lipase enzyme inhibitory. Based on overall analysis of the data, we recommend OHAE as an optimal technique providing saffron petals extracts having the highest combination of bioactives compounds in reasonably extraction time.