A high-speed counter-current chromatographic (HSCCC) method using ethyl acetate–water as solvent system was established to separate isoquercetin from Toona sinensis. In an HSCCC single separation, the sample sizes of ethanol extract were optimized from 203 to 1200 mg. The results showed that the yield of the target compound increased from 4 to 26 mg, and the corresponding purity decreased from 93.30 to 81.82%. To further improve the yield and purity, liquid–liquid-refining extraction was introduced to pretreat the ethanol extract and enrich the target compound. The ethanol extract was extracted with n-hexane-ethyl acetate-method-water (1:5:1:5, v/v) and ethyl acetate-water in turn to remove the low-polarity and high-polarity impurities and obtain the crude sample. Under the similar conditions, 85.25 mg of the target compound with the purity of 95.12% was separated from 240 mg of the crude sample. Subsequently, a consecutive HSCCC was developed to obtain 257 mg of the target compound from 720 mg of crude sample, which was equivalent to 14.4 g of ethanol extract. This method improved the purity of the target compound, but more importantly, the sample size can reach 12 times of the maximum sample size of the ethanol extract in a single run.

中文翻译：

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液-液精制萃取连续逆流色谱法制备香椿中异槲皮素


建立了以乙酸乙酯-水为溶剂体系分离香椿中异槲皮素的高速逆流色谱（HSCCC）方法。在 HSCCC 单次分离中，乙醇提取物的样品量从 203 mg 优化至 1200 mg。结果表明，目标化合物的收率从4mg增加到26mg，相应的纯度从93.30%下降到81.82%。为进一步提高收率和纯度，采用液液精制萃取法对乙醇提取物进行预处理，富集目标化合物。乙醇提取液依次用正己烷-乙酸乙酯-水(1:5:1:5, v/v)、乙酸乙酯-水萃取，除去低极性和高极性杂质，得粗样品。在相似条件下，从240mg粗样品中分离得到85.25mg目标化合物，纯度为95.12%。随后，进行连续HSCCC，从720mg粗样品中获得257mg目标化合物，相当于14.4g乙醇提取物。该方法提高了目标化合物的纯度，但更重要的是，单次样品量可以达到乙醇提取物最大样品量的12倍。