Optimization of the Extraction Process of Anthocyanins from Perilla Leaves and Their Antioxidant and Antibacterial Activities

In order to determine the optimal extraction process, and antioxidant and antibacterial activities of anthocyanins from Perilla friesians leaf, in this study, Perilla friesians leaf was used as raw material. Response surface method was used to optimize the optimal process conditions of ultrasonic-assisted extraction of anthocyanins from Perilla friesians leaf, and liquid mass combined technology was used to conduct qualitative and quantitative analysis of anthocyanins and anthocyanins in the extracts. The antioxidant activity and antibacterial activity of the extracts were studied. The results showed that the optimum conditions were as follows: The ratio of material to liquid was 1:20 g/mL, the ultrasonic temperature was 47 ℃, the ultrasonic time was 57 min, and ethanol concentration was 62%, and the maximum extraction rate was 7.18±0.32 mg/g DW under these conditions. The extract was mainly composed of cyanidin, delphinidin 3-O-glucoside, and cyanidin 3-O-glucoside. The extract showed significant scavenging activity on DPPH and ABTS⁺ free radicals, and the IC₅₀ values were 0.49 and 0.32 mg/mL, respectively. The lowest inhibitory concentration against Staphylococcus aureus was 160 mg/mL. This study provides a theoretical basis for the extraction and application of anthocyanins from Perilla friesians leaf.