Abstract: Total flavonoids in Taraxacum mongolicum are a highly effective medicine，and aqueous two-phase extraction process is an effective technique for extracting biomaterials from plant. Effect of molecular weight and mass fraction of PEG，mass fraction of (NH4)2SO4，temperature and pH of aqueous two-phase system were investigated during extraction of total flavonoids from Taraxacum mongolicum. The optimal extraction conditions were obtained through orthogonal experiments. The optimal condition thus obtained is as follows：the average molecular weight of PEG at 1000，the mass fraction of PEG1000 at 23%，the mass fraction of (NH4)2SO4 at 18%，temperature at 25℃，pH at 5.34. The NaCl addition has little effect on flavonoids partition. The extraction yield of total flavonoids from Taraxacum mongolicum can reach up to 5.47% under this optimal condition. Compared with other extraction methods，the aqueous two-phase extraction process is a more environment-friendly and highly efficient technique.

Key words: Taraxacum mongolicum, total flavonoids, aqueous two-phase system, partition, extraction

摘要： 蒲公英中内含的黄酮类物质具有较高药用价值，用双水相萃取法提取植物中有效成分是新型提取高附加值生物质的有效方法。本文考察了PEG/(NH4)2SO4双水相体系萃取分离蒲公英总黄酮时聚乙二醇相对分子质量、PEG质量分数、(NH4)2SO4质量分数、温度、pH值5个因素对分配行为的影响，并通过正交实验优化了工艺条件。结果表明最佳双水相提取工艺条件为：(NH4)2SO4质量分数18%，PEG1000质量分数23%，pH值5.34，提取温度25℃，NaCl盐的存在与否对萃取影响很小，蒲公英中总黄酮的提取率可达5.47%。因此，使用双水相法提取蒲公英总黄酮是该类提取技术中一种更加绿色环保和高效的方法。

关键词: 蒲公英, 总黄酮, 双水相, 分配, 提取