Abstract: The separation of lithospermic acid B (LAB) by aqueous two-phase systems was studied. According to the partition coefficient and the yield of LAB, the various ethanol and (NH4)2SO4 system were investigated using response surface methodology to find the optimal condition. The results showed that the optimum phase composition was 20% (w) (NH4)2SO4 and 29% (w) of ethanol for crude extraction at pH2.0 and 30 oC. The partition coefficient and yield　of LAB were 58.7 and 97.3% respectively. To remove the salt, the purity is 57.4%. Compared with small scale, the partition coefficient (59.3), yield (98.2%) and purity (58.6%) of LAB are no significant different in scale up 40 folds. Subsequently, the (NH4)2SO4 was removed from the top phase with ethanol. The concentrated extracts were partitioned with chloroform, and the H2O layer was extracted by EtOAc. The EtOAc fraction was evaporated in vacuo at 40 oC, and 26.1g LAB with the purity of 78.1% and the overall yield of 87.0% was obtained from 500g powders. Thus aqueous two-phase system may provide efficient technique for extraction of LAB from the crude extract.

Key words: lithospermic acid B, aqueous two-phase extraction, ethanol/ammonium sulphate, response surface methodology

摘要： 采用中心复合设计的响应曲面法优化了乙醇/硫酸铵双水相体系从丹参粗提液中分离丹酚酸B的工艺参数，并对放大效果进行了对比研究。结果表明，在确定pH2.0和30℃的条件下，当硫酸铵和乙醇质量分数分别为20%和29%时，丹酚酸B的分配系数最大为58.7，回收率为97.3%。上相加乙醇脱除硫酸铵，减压浓缩、干燥，丹酚酸B的纯度为57.4%。与小试相比，放大40倍后，分配系数(59.3)、回收率(98.2%)和纯度（58.6%）均无显著差异（p<0.05）。500g丹参，经煮提，双水相萃取，脱硫酸铵，氯仿脱脂，乙酸乙脂萃取，可得26.1g浸膏，丹酚酸B的纯度为78.1%，总回收率为87.0%。因此，双水相萃取可以作为从丹参粗提液中规模分离丹酚酸B的有效手段。

关键词: 丹酚酸B, 双水相萃取, 乙醇/硫酸铵, 响应面分析