乙醇/硫酸铵双水相体系从丹参粗提液中分离丹酚酸B

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。

A new aqueous two-phase system of ethanol/ammonium sulphate for recovery of lithospermic acid B from extract of Salvia miltiorrhiza Bge

The separation of lithospermic acid B(LAB)from crude extract of Radix Salivae miltiorrhizae by aqueous two-phase systems was studied.According to the partition coefficient and the yield of LAB,various ethanol and(NH4)2SO4 systems were used and examined with response surface methodology to find the optimal condition.The results showed that the optimum phase composition was 20%(mass)of(NH4)2SO4 and 29%(mass)of ethanol for crude extraction at pH 2.0 and 30℃.The partition coefficient and yield of LAB were 58.7 and 97.3% respectively.After removal of the salt,the purity of LAB is 57.4%.Compared with this small scale experiment,the difference in partition coefficient(59.3),yield(98.2%)and purity(58.6%)of LAB are insignificant for a large scale experiment of 40 folds.Subsequently,(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℃,and 26.1 g LAB with the purity of 78.1% and the overall yield of 87.0% was obtained from 500 g Radix Salivae miltiorrhizae powder.Thus the aqueous two-phase system may provide an efficient technique for extraction of LAB from the crude extract.