超临界CO2萃取工艺条件对栀子油脂肪酸组成及其抗氧化活性的影响

利用气相色谱(GC)测定栀子油脂肪酸组成。结果显示栀子油中主要含有5种脂肪酸，即亚油酸、油酸、棕榈酸、硬脂酸和亚麻酸。在萃取压力30MPa、温度55℃、CO2流速15kg/h条件下分别占44.38%、24.96%、24.83%、2.55%、1.31%。萃取压力、温度、CO2流速对其脂肪酸组成具有一定的影响，但不显著。通过清除DPPH和ABTS自由基，得出栀子油具有一定的抗氧化活性。不同萃取压力、温度、CO2流速对栀子油清除DPPH和ABTS自由基的能力具有不同程度的影响。

Effect of Supercritical Carbon Dioxide Extraction Conditions on Fatty Acid Composition and Antioxidant Activity of Gardenia Fruit Oil

The fatty acid composition of gardenia fruit oils extracted with supercritical CO2 under varying conditions of pressure, temperature and CO2 flow rate was determined by gas chromatography. The results showed that there were mainly 5 fatty acids in gardenia fruit oil, namely linoleic acid, oleic acid, palmitic acid, stearic acid and linolenic acid, of which the contents were respectively 44.38%, 24.96%, 24.83%, 2.55% and 1.31% in the oil extracted under 30 MPa, 55 ℃ and CO2 flow rate of 15 kg/h. Each of the three extraction conditions had some effect on the composition of fatty acids in gardenia fruit oil, which showed no statistical significance. It was found that gardenia fruit oil had the ability to scavenge DPPH and ABTS+ free radicals, indicating its antioxidant activity. Moreover, extraction pressure, temperature and CO2 flow rate could affect the DPPH and ABTS+ free radical scavenging activities of gardenia fruit oil to different extents.