关键词: 甘草黄酮, 甘草酸, 萃取, 分离, 正交实验

Abstract: Using the mixture of trialkylphosphine oxide (TRPO) and petroleum ether as extractive organic phase, the extraction of hydrophilic flavonoid from the aqueous leaching solution of licorice was carried out. Orthogonal tests showed that the concentration of TRPO was the most remarkable factor for extracting hydrophilic flavonoid, then the phase ratio and the smallest was pH value. It was also found that the extraction rate of total flavonoid (TF) decreased with increasing pH value in the range from 5 to 8. The extraction rate of glycyrrhizic acid rapidly decreased with increasing pH value in the range from 5 to 6, and it almost approached zero above pH 6. The extraction rate of TF rapidly increased with the increase of the concentration of TRPO and decreased with the increase of phase volume ratio (A/O). It decreased with the increase of the system temperature, and the reaction of the extracting TF was exothermic. The ratio of TRPO to solute in extractive complex was 3. The separation between hydrophilic licorice flavonoids and glycyrrhizic acid in the aqueous leaching solution could be achieved by solvent extraction method.

Key words: licorice flavonoid, glycyrrhizic acid, extraction, separation, orthogonal test