Cimicifuga racemosa products are widely used in the treatment of climacteric symptoms. The aim of this study was to evaluate C racemosa extract Ze 450 according to Biopharmaceutics Classification System (BCS). Triterpene glycosides served as analytical marker and were evaluated for solubility and absorption properties. pH-dependent thermodynamic solubility was tested via shake flask method, and dissolution performance of a herbal medicinal product containing C racemosa extract Ze 450 was assessed. Absorption was estimated by in vitro permeation through Caco-2 monolayers. Furthermore, different intestinal segments were screened for absorption performance using an in situ rat model. Over a physiological pH range, triterpene glycosides exhibited pH-dependent solubility with highest concentration at pH 7.5. Dissolution profiles showed rapid dissolution of actein and 23-epi-26-deoxyactein. Furthermore, 23-epi-26-deoxyactein as surrogate for contained triterpene glycosides showed a high permeability through Caco-2 monolayers. Results of in situ rat model showed absorption capacity for 23-epi-26-deoxyactein in duodenum, jejunum, ileum, and colon. The results indicate high bioavailability of triterpene glycosides from C racemosa extract Ze 450. With regard to BCS, triterpene glycosides can be classified into BCS class I (high solubility, high permeability).

中文翻译：

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车前草提取物中三萜糖苷的体外和原位表征。

消旋状升麻产品被广泛用于治疗更年期症状。这项研究的目的是根据生物制药分类系统（BCS）评估消旋C消脂提取物Ze 450。三萜糖苷用作分析标记，并评估其溶解度和吸收特性。通过摇瓶法测试了pH依赖性的热力学溶解度，并且评估了含有消旋C提取物Ze 450的草药的溶解性能。通过Caco-2单层的体外渗透来估计吸收。此外，使用原位大鼠模型筛选不同肠段的吸收性能。在生理pH范围内，三萜糖苷显示出pH依赖性的溶解度，在pH 7.5下具有最高浓度。溶出曲线显示肌动蛋白和23-epi-26-脱氧肌动蛋白迅速溶解。此外，作为所含三萜糖苷的替代物的23-epi-26-脱氧肌动蛋白显示出通过Caco-2单层的高渗透性。原位大鼠模型的结果显示十二指肠，空肠，回肠和结肠对23-epi-26-脱氧肌动蛋白的吸收能力。结果表明，来自总状花序提取物Ze 450的三萜糖苷具有很高的生物利用度。就BCS而言，三萜糖苷可分类为BCS I类（高溶解度，高渗透性）。