超临界CO_2萃取当归油的工艺及当归多糖的提取

Technological Studies on the Supercritical Carbon Dioxide Fluid Extraction of Oils and Polysacchrides from Chinese Angelica

目的 采用超临界 CO2萃取技术从当归中萃取当归油,对提油后的药渣采用水煎法提取当归多糖。方法 通过正交试验探讨了不同压力、温度、流量等因素对当归油萃取率的影响。结果与结论 当萃取压力为 25 mPa、萃取温度为 45 ℃、CO2流量为 40 L/h、萃取时间 2 h 时,当归油得率最高。当归多糖的最佳提取工艺参数为:固液比(kg/L)1∶6, 浸提时间 2 h,醇沉浓度 60%,浸提温度 85 ℃,当归总多糖得率为 14.32%。

Objective The supercritical CO2 fluid technique was employed to extract the essential oils from the Chinese angelica, followed by boiling its residues and leaching to extract further polysaccharides. Method The factorial designed experiments were carried out to investigate extensively the effect of different factors, such as pressure, temperature and flow rate, on the extraction efficiency of oils from angelica. Result and Conclusion The result shows that the maximum extraction efficiency was obtained at the extraction pressure 25 mPa and temperature 45 ℃ in 2 h with CO2 flow rate of 40 L/h. The optimum technological parameters for the extraction of polysaccharides from angelica were also discussed and found to be the solid-to-liquid ratio of 1∶6 (kg/L) and extraction temperature of 85 ℃ with the alcohol concentration for precipitation of 60% in the extraction time of 2 h. Under those conditions, the yield of polysaccharides was obtained at around 14.32%.