School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China.
College of Marine Science and Environment, Dalian Ocean University, Dalian 116023, China.
J Chromatogr A. 2022 Jan 4;1661:462717. doi: 10.1016/j.chroma.2021.462717. Epub 2021 Nov 27.
Large-scale preparation of target compounds from complex samples is facing great challenges. In the present study, an efficient strategy for large-scale preparation of target compound was proposed and successfully applied in the separation of active components from Toona sinensis. The pretreatment technology of liquid-liquid refining extraction (LLRE) combined with consecutive high-speed counter-current chromatography (HSCCC) was used to process hundred grams of extractions. Firstly, two phase solvent systems composed of n-hexane-ethyl acetate-methanol-water (5:5:5:5, v/v) and (2:5:2:5, v/v) were used to remove low polar and high polar impurities from 100 g crude extracts of T. sinensis, respectively, and 9.25 g of crude sample was obtained. And then, n-hexane-ethyl acetate-methanol-water (2.5:5:2.5:5, v/v) was used as the solvent system for HSCCC separation. The isocratic elution mode with max loading and consecutive injections mode were investigated to obtain more target compound. As a result, ethyl gallate with purity of 97% was successfully separated by 5 times consecutive counter-current chromatography. The separation was repeated once. Finally, ethyl gallate (3.73 g) was isolated from 9.25 g of crude sample (100 g crude extracts). The results demonstrated that the yield increased from 0.26 g/h/L of untreated crude extract to 0.93 g/h/L of LLRE pre-treated sample for single injection, and further increased to 1.62 g/h/L for 5 consecutive injections mode with the present method.
从复杂样品中大规模制备目标化合物面临巨大挑战。在本研究中，提出了一种从香椿中分离活性成分的高效策略，并成功应用于大规模制备目标化合物。采用液-液精炼萃取（LLRE）与连续高速逆流色谱（HSCCC）相结合的预处理技术，对百克提取物进行处理。首先，分别使用由正己烷-乙酸乙酯-甲醇-水（5:5:5:5，v/v）和（2:5:2:5，v/v）组成的两相溶剂系统从 100 g 香椿粗提取物中去除低极性和高极性杂质，分别得到 9.25 g 粗样品。然后，使用正己烷-乙酸乙酯-甲醇-水（2.5:5:2.5:5，v/v）作为 HSCCC 分离的溶剂系统。考察了最大负载和连续进样模式的等度洗脱模式，以获得更多的目标化合物。结果，成功地通过 5 次连续逆流色谱分离出纯度为 97%的没食子酸乙酯。分离重复一次。最终，从 9.25 g 粗样品（100 g 粗提取物）中分离出 3.73 g 没食子酸乙酯。结果表明，与未经处理的粗提取物相比，单注时未处理粗提取物的产率从 0.26 g/h/L 增加到 LLRE 预处理样品的 0.93 g/h/L，采用本方法进一步增加到 5 次连续进样模式的 1.62 g/h/L。
