Study on biological activity of perilla seed oil extracted by supercritical carbon dioxide

In this study, supercritical carbon dioxide extraction (SC–CO2) was used to extract perilla seed oil. Box-Behnken experimental design and response surface method were used to optimize process conditions. The optimal process conditions with the extraction rate (%) as the dependent variable are: pressure 33.98 MPa, temperature 42 °C, CO2 flow rate 29.25 L/h. Gas chromatography-mass spectrometry component analysis, antibacterial and antioxidant activity, total phenolics and flavonoid content, schall oven test were used to evaluate the physiological activity and storage stability of perilla seed oil. The main fatty acid of perilla seed oil obtained by SC-CO2 are linolenic acid (78.7%). Meanwhile, the comparison between the oil extracted by SC-CO2, pressing extraction (PO), petroleum ether extraction (PEO) and the commercial edible oil (CO) shows that the perilla seed oil obtained by SC-CO2 has more total phenolics (130.4 mg/100 g) and flavonoids (35.3 mg/100 g), and it has broad-spectrum antibacterial activity, antioxidant activity (DPPH EC50 = 7.01 mg/mL, ABTS EC50 = 12.75 mg/mL, reducing power AC50 = 4.3 mg/mL) and storage stability. This study confirmed the nutritional value and bioactivity of perilla seed oil, and proves that SC-CO2 has the potential to be used in the food industry.