琉璃苣籽油富含油酸、亚油酸和 y-亚麻酸，琉璃苣籽油具有很高的营养价值和健康效益。然而传统制备方法为压榨法以及溶剂萃取法，压榨法油脂得率低，‚有机溶剂萃取法存在溶剂回收难和产品有溶剂残留等问题。超临界 CO2流体萃取，是一种先进且日益广泛的分离技术。其优点在于能够无有机污染地提取和保留热敏性成分，产品纯度高、收率高，特别适用于提取天然动植物中的有效成分。

Borage seed oil is rich in oleic acid, linoleic acid and Y-linolenic acid, which has high nutritional value and health benefits. However, the traditional preparation methods are pressing and solvent extraction. The oil yield of pressing method is low, but the solvent recovery of organic solvent extraction method is difficult and the solvent remains in the product.Supercritical CO₂ fluid extraction is an advanced and increasingly widespread separation technology. Its advantages lie in the ability to extract and retain thermosensitive components without organic pollution, with high product purity and yield, making it particularly suitable for extracting effective ingredients from natural animals and plants.

超临界 CO₂ 流体萃取琉璃苣籽油的工艺流程采用了“一萃二分”的方法。具体流程为：将 600ｇ粉碎后的琉璃苣籽投入萃取釜中，对萃取釜、分离釜、储罐进行加热或冷却。当各部分达到设定温度后，开启 CO₂ 钢瓶，CO₂ 气体经净化器净化后进入冷（0℃ ）液化，由高压调频柱塞泵送入预热器预热，再经净化进入萃取釜升压到预定设置值，使 CO₂ 转成超临界流体对琉璃苣籽中的油脂进行萃取。CO₂ 经分离釜减压与萃出物分离后循环使用。

The process flow of supercritical CO₂ fluid extraction for borage seed oil employs the "one extraction and two fractions" method. The specific process is as follows ：placing 600g of crushed borage seeds into an extraction kettle, and heating or cooling the extraction kettle, separation kettle, and storage tank. Once each component reaches the desired temperature, Open the CO₂ cylinder.After the CO2 gas is purified by the purifier, it enters cold (0℃) to liquefy, and is sent to the preheater by the high pressure frequency modulated plunger pump. After purification, the CO₂ enters the extraction kettle where it is pressurized to the predetermined set value, converting it into a supercritical fluid for extracting the oil from the borage seeds. The CO₂ is then depressurized in the separation kettle and separated from the extract.

琉璃苣籽油的超临界 CO₂ 流体萃取研究考察了多个工艺参数对出油率的影响，包括萃取压力、萃取温度、萃取时间和 CO₂流量，最终确定了最佳工艺条件为：萃取压力 25MPa，萃取温度 45℃，萃取时间 2.5h，CO 流量 45L/h。在此条件下，出油率达到了 28.08%。

The study on supercritical CO₂ fluid extraction of borage seed oil investigated the effects of multiple process parameters on oil yield, including extraction pressure, extraction temperature, extraction time, and CO₂ flow rate. The optimal process conditions were ultimately determined to be: extraction pressure of 25MPa, extraction temperature of 45 ℃, extraction time of 2.5h, and CO₂ flow rate of 45L/h. Under these conditions, the oil yield reached 28.08%.

图1 超临界 CO₂流体萃取工艺流程图

Fig1 Supercritical CO₂ fluid extraction process flow chart

样品处理：取琉璃苣籽油0.5 mL加入2.0 mL正己烷，再加入1.0 mL氢氧化钠甲醇溶液(0.5 mol/L)，置于水浴上70 ℃回流10min取出冷却后移至刻度试管中，加入10mL水，振荡，超声提取，离心，取其上清液做气相色谱(GC)分析。

气相色谱分析条件﹑色谱柱FFAP(30 m×0.32 mmX0.33um )；升温程序:初始温度100℃，以10℃/m in速率升至280℃，保持15 m in汽化温度280℃；载气流量1 mL/min分流比50∶1；检测器温度(FID)280℃；进样量1uL。

根据保留时间定性，面积归一化法定量。

Sample processing: Take 0.5 mL of borage seed oil and add 2.0 mL of n-hexane, then add 1.0 mL of sodium hydroxide methanol solution (0.5 mol/L), place it on a water bath at 70 ℃ and reflux for 10 minutes. After cooling, transfer it to a graduated test tube, add 10 mL of water, shake, sonicate, centrifuge, and take the supernatant for gas chromatography (GC) analysis.

Gas chromatography analysis conditions, chromatographic column FFAP (30 m) × 0.32 mmX0.33um); Heating program: Initial temperature of 100 ℃, increase to 280 ℃ at a rate of 10 ℃/min, and maintain the vaporization temperature of 280 ℃ for 15 min; Carrier gas flow rate of 1 mL/min split ratio of 50:1; Detector temperature (FID) 280 ℃; Inject 1uL of sample.

Qualitative analysis based on retention time and quantitative analysis using area normalization method.

萃取压力对出油率的影响如图2所示，结果表明在15~30 MPa范围内出油率随萃取压力的升高而逐渐升高，随萃取压力升高，萃取出的琉璃苣籽油色泽变暗，可能是由于高压下某些色素成分被萃取出来的缘故。

The effect of extraction pressure on oil yield is shown in Figure 2. The results show that the oil yield gradually increases with the increase of extraction pressure in the range of 15-30 MPa. As the extraction pressure increases, the color of the extracted borage seed oil becomes darker, possibly due to the extraction of certain pigment components under high pressure.

图2萃取压力对出油率的影响

Fig2 The influence of extraction pressure on oil yield

在萃取压力25 MPa CO₂流量50L/h萃取时间2.5 h条件下，考察萃取温度对出油率的影响，结果见图3，结果在35~55℃范围内，萃取温度对出油率的影响呈先上升后下降的趋势。

Under the condition of extraction pressure of 25 MPa, CO₂ flow rate of 50 L/h, and extraction time of 2.5 h, the effect of extraction temperature on oil yield was investigated. The results are shown in Figure 3, and within the range of 35-55 ℃, the effect of extraction temperature on oil yield showed a trend of first increasing and then decreasing.

图3 萃取温度对出油率的影响

Fig3 The influence of extraction temperature on oil yield

萃取时间和CO₂流量对超临界萃取的影响:在萃取压力25 MPa萃取温度45℃条件下，考察了不同CO₂流量在不同萃取时间下的影响，结果如图4。结果随萃取时间的延长，出油率逐渐增加，在萃取的前60 m in内，出油率几乎呈线性增加，随后增加减缓。.

The effects of extraction time and CO₂ flow rate on supercritical extraction: Under the extraction pressure of 25 MPa and extraction temperature of 45 ℃, the effects of different CO₂ flow rates at different extraction times were investigated, and the results are shown in Figure 4. As the extraction time prolonged, the oil yield gradually increased. Within the first 60 minutes of extraction, the oil yield almost linearly increased, followed by a slowdown in the increase.

图4 萃取时间和CO₂流量对出油率的影响

Fig4 The influence of extraction time and CO2 flow rate on oil yield

结论：最佳萃取条件为萃取压力25 MPa萃取温度45℃，萃取时间2.5 hCO2，流量45 L/h。

Conclusion: The optimal extraction conditions are extraction pressure of 25 MPa, extraction temperature of 45 ℃, extraction time of 2.5 h CO2, and flow rate of 45 L/h.

超临界流体在各大领域中都能得到广泛的应用。在化学反应中，超临界流体可以作为溶剂或反应介质，用于合成有机化合物、高分子材料和纳米材料等。由于超临界流体的介电常数和溶剂化能力会随着压力的增加而发生变化，因此可以用来控制化学反应的速率和方向，提高产物的纯度和选择性。

在天然产物萃取方面，超临界流体可以有效地萃取植物、动物和微生物中的活性成分，如色素、香料、油脂和药用成分等。相比于传统的萃取方法，超临界流体萃取具有更高的提取效率和选择性，能够获得更好的产品质量和经济效益。Supercritical fluids can be widely applied in various fields. In chemical reactions, supercritical fluids can serve as solvents or reaction media for the synthesis of organic compounds, polymer materials, and nanomaterials. Due to the fact that the dielectric constant and solvation ability of supercritical fluids change with increasing pressure, they can be used to control the rate and direction of chemical reactions, improve product purity and selectivity.

In terms of natural product extraction, supercritical fluid can effectively extract active ingredients from plants, animals, and microorganisms, such as pigments, spices, oils, and medicinal ingredients. Compared to traditional extraction methods, supercritical fluid extraction has higher extraction efficiency and selectivity, which can achieve better product quality and economic benefits.