深共熔溶剂同步提取红景天中红景天苷和酪醇

采用深共熔溶剂(Deep eutectic solvents, DESs)法同步提取红景天中红景天苷和酪醇. 首先, 通过对氢键供体(HBD)、 氢键受体(HBA)及二者摩尔比和DESs含水量等因素的设计优化, 获得了同步提取红景天苷和酪醇的最佳DES为乙二醇-乙酰丙酸(摩尔比为1∶1), 含水质量分数为40%, 记为LAEG-40. 然后, 以LAEG-40作提取溶剂, 对提取方法、 料液比、 提取温度及提取时间等因素进行优化, 获得了最佳提取条件: 采用150 r/min搅拌速率提取, 料液比为1∶12.5(g/mL), 提取温度60 ℃, 提取时间65 min. 在此条件下LAEG-40对红景天苷的提取率可达(18.1268±0.1667) mg/g, 酪醇提取率可达(1.5608±0.0240) mg/g. 而在相同条件下, 以水和乙醇作为提取溶剂, 红景天苷提取率分别为(15.1221±0.1342)和(16.3425±0.0897) mg/g, 酪醇提取率分别为(1.1120±0.0389)和(1.1923±0.0423) mg/g, 可见LAEG-40的提取效果明显高于传统溶剂. 研究结果表明, LAEG-40是一种绿色、 高效的红景天苷和酪醇同步提取溶剂, 可用于替代传统溶剂.

Simultaneous Extraction of Salidroside and Tyrosol from Rhodiolarosea L. Using Tailor-made Deep Eutectic Solvents†

A method for simultaneously extracting the salidroside and tyrosol from Rhodiolarosea L. using deep eutectic solvents(DESs) as the extraction solvents was developed in this work. Firstly, the hydrogen bond donor(HBD), hydrogen bond acceptor(HBA), molar ratio of HBA to HBD, and water content were optimized. The optimal DES for the simultaneous extraction was obtained as ethylene glycol-levulinic acid at the molar ratio of 1∶1 and water content of mass fraction of 40%, which was recorded as LAEG-40. Then, taking the LAEG-40 as the extraction solvent, the extraction conditions such as extraction method, solid to solvent ratio, extraction temperature and extraction time were further optimized. The optimal conditions were obtained as follows: stirring extraction at the solid to solvent ratio of 1∶12.5(g/mL) and 60 ℃ for 65 min. Under these conditions, the extraction yields of salidroside and tyrosol reached (18.1268±0.1667) and (1.5608±0.0240) mg/g, respectively. However, under the same conditions, taking water or ethanol as the extraction solvents, the extraction yields of salidroside and tyrosol were (15.1221±0.1342) and (1.1120±0.0389) mg/g, or (16.3425±0.0897) and (1.1923±0.0423) mg/g, respectively. It could be seen that the extraction efficiency of LAEG-40 was obviously higher than those of traditional solvents. The results showed that LAEG-40 was a green and efficient solvent for simultaneous extraction of salidroside and tyrosol, which could be used as a substitute for traditional solvents.