目的 研究溶液环境对甘草皂苷超滤分离的影响规律，结合成分状态探索其分离机制。方法 以甘草提取液为研究对象，选择膜通量、吸附率和透过率为考察指标，分析pH值、温度、质量浓度等溶液环境因素对甘草皂苷超滤分离行为的影响，结合扫描电子显微镜（SEM）物态表征，推测甘草皂苷的超滤分离机制。结果 随pH值升高，甘草酸膜通量由48.10 L/(m²∙h)增加至55.20 L/(m²∙h)，吸附率由87.29%减少至32.05%，透过率由97.33%降低至81.18%；甘草提取液膜通量由47.47 L/(m²∙h)增加至49.74 L/(m²∙h)，吸附率由99.34%减少至25.43%，透过率由89.52%降低至60.00%。随温度升高，甘草酸膜通量由45.99 L/(m²∙h)增加至67.39 L/(m²∙h)，吸附率约40%、透过率约80%；甘草提取液膜通量由38.94 L/(m²∙h)增加至58.01 L/(m²∙h)，吸附率约30%、透过率约68%。随着质量浓度升高，甘草酸膜通量由48.99 L/(m²∙h)降低至42.51 L/(m²∙h)，吸附率由45.25%减少至20.18%，透过率由71.09%降低至60.01%；甘草提取液膜通量由49.56 L/(m²∙h)降低至41.25 L/(m²∙h)，吸附率由40.60%减少至13.99%，透过率由73.96%降低至46.65%。其中，pH值、温度、质量浓度对膜通量影响显著（P＜0.05），pH值、质量浓度显著影响甘草酸的吸附率、透过率（P＜0.05）。相较于甘草酸单体，甘草提取液中甘草酸的透过率、吸附率波动范围较小，且膜通量相对稳定。对比单体和甘草提取液的SEM物态特征，提取液中形成的多成分缔合物的尺寸小于甘草酸胶团，是导致二者超滤分离行为差异的核心机制。结论 通过系统地考察溶液环境对甘草皂苷的超滤分离行为的影响，并结合微观物态特征分析其影响机制，为中药复杂溶液体系下皂苷类成分的分离研究提供技术支撑。

Objective To explore the effect of solution environment on the ultrafiltration separation of glycyrrhizin and the separation mechanism combined with the composition state. Methods Taking licorice extract as the research object, the membrane flux, adsorption rate and transmittance were selected as the evaluation indexes to analyze the effects of solution environmental factors such as pH value, temperature and concentration on the ultrafiltration separation behavior of glycyrrhizin. Combined with the characterization of scanning electron microscopy (SEM), the ultrafiltration separation mechanism of glycyrrhizin was speculated. Results With the increase of pH value, the flux of glycyrrhizic acid increased from 48.10 L/(m²∙h) to 55.20 L/(m²∙h), the adsorption efficiency decreased from 87.29% to 32.05%, and the permeability decreased from 97.33% to 81.18%; The membrane flux of licorice extract increased from 47.47 L/(m²∙h) to 49.74 L/(m²∙h), the adsorption rate decreased from 99.34% to 25.43%, and the permeability decreased from 89.52% to 60.00%. The flux of glycyrrhizic acid increase from 45.99 L/(m²∙h) to 67.39 L/(m²∙h) with the increase of solution temperature, the adsorption rate was about 40% and the permeation rate was about 80%; The membrane flux of licorice extract increased from 38.94 L/(m²∙h) to 58.01 L/(m²∙h), the adsorption rate was about 30% and the permeability was about 68%. With the increase of the concentration of glycyrrhizic acid in the solution, the flux of glycyrrhizic acid membrane decreased from 48.99 L/(m²∙h) to 42.51 L/(m²∙h), the adsorption rate decreased from 45.25% to 20.18%, and the permeability decreased from 71.09% to 60.01%; The membrane flux of licorice extract decreased from 49.56 L/(m²∙h) to 41.25 L/(m²∙h), the adsorption rate decreased from 40.60% to 13.99%, and the permeability decreased from 73.96% to 46.65%. Among them, pH value, temperature, concentration have significant effects on the membrane flux (P < 0.05), and pH value, concentration of glycyrrhizic acid in the two solutions of the adsorption rate, permeability were significantly affected (P < 0.05). Compared with glycyrrhizic acid monomer, the transmittance and adsorption rate of glycyrrhizic acid in licorice extract fluctuated in a small range, and the flux was relatively stable. Comparing the electron microscopic state characteristics of the monomer and the licorice extract, the size of the multi-component association complex formed in the extract is smaller than that of the glycyrrhizic acid micelle, which is the core mechanism leading to the difference in ultrafiltration separation behavior between the two. Conclusion The effect of solution environment on the ultrafiltration separation behavior of glycyrrhizin was systematically investigated, and the influence mechanism was analyzed combined with the microscopic physical state characteristics, which provided technical support for the separation of glycyrrhizin in complex solution system of traditional Chinese medicine.

R283.6

国家自然科学基金资助项目（82274106）；国家自然科学基金资助项目（81603307）；江苏省自然科学基金资助项目（BK20211303）