超临界CO_2萃取大黄总蒽醌工艺研究

Supercritical CO_2 extraction of total anthraquinones from Rheum Palmatum L.

对大黄游离蒽醌的超临界萃取工艺进行了优化,确定最优萃取工艺条件为:静萃取时间60 m in,动萃取时间30 m in,夹带剂乙醇相对大黄用量3 mL/g,萃取温度45℃,萃取压力45 MPa。然后分别采用无机酸和生物酶对大黄结合蒽醌进行水解,以提取总蒽醌。结果表明:当盐酸浓度为5 mol/L,淀粉酶质量浓度为2 g/L,纤维素酶质量浓度为1 g/L时,大黄结合蒽醌的糖苷键达到最优水解,此时总蒽醌质量分数分别为2.46%、2.33%和2.23%。

A technical process for extracting total anthraquinones with supercritical CO2 was studied. The optimal parameters of the supercritical fluid extraction of liber anthraquinones were determined： static extraction time 60 min, dynamic extraction time 30 min, ethanol used as a modifier with a amount of 3 mL/g Rheum palmatum L. powder, extraction temperature 45℃, and extraction pressure 45 MPa. Inorganic acids and bio-enzymes were used to hydrolyze the glycoside bond in combined anthraquinones to obtain the total anthraquinones. The results show that the hydrolysis degree can reach the maximum when the concentration of chlorhydric acid, amylase and cellulase is 5 mol/L, 2 g/L and 1 g/L, respectively, at which the mass fraction of the total anthraquinones is 2.46%, 2.33% and 2.23%, respectively.