目的 考察桂枝甘草汤中甘草酸、甘草苷、异甘草苷、甘草素、异甘草素、苯甲酸钠、香豆素、桂皮醇、桂皮酸、桂皮醛10种成分在不同煎煮时间下的变化。方法 采用HPLC-DAD多波长切换法同时测定不同煎煮时间（10、20、30、40、50、60、90 min）下桂枝甘草汤中10种成分。Hypersil Gold-C₁₈色谱柱（250 mm×4.6 mm，5 μm）；流动相：乙腈-0.1%磷酸溶液，梯度洗脱；体积流量：0.8 mL/min；柱温：20℃；进样量：20 μL；检测波长：230 nm（甘草苷、甘草素、苯甲酸钠）、254 nm（甘草酸，桂皮醇）、276 nm（香豆素、桂皮酸、桂皮醛）、370 nm（异甘草苷、异甘草素）。结果 随着煎煮时间的延长，10种成分的总量在30 min处达到最大值，且最终趋向稳定；桂枝中各成分的变化大体上是先增加后减少，在30 min处达到最大值；炙甘草中各成分量的变化除了在40 min处有减少外，基本呈现递增趋势。结论 确定桂枝甘草汤的煎煮时间为30 min，为其临床应用提供了科学依据。

Objective To investigate the changes of 10 components, such as glycyrrhizic acid, liquiritin, isoliquiritin, isoliquiritigenin, liquiritigenin, sodium benzoate, coumarin, cinnamic alcohol, cinnamic acid, and cinnamaldehyde in Guizhi Gancao Decoction at various decocting time. Methods The contents of 10 active components in Guizhi Gancao Decoction decocted with different decocting time (10, 20, 30, 40, 50, 60, and 90 min) were simultaneously determined by HPLC-DAD with changing ultraviolet-visible wavelength. Diamonsil C₁₈ column (250 mm×4.6 mm, 5 μm) was carried out. The mobile phase was acetonitrile-0.1% phosphoric acid solution (H₃PO₄) with gradient elution, with a flow rate of 0.8 mL/min. The column temperature was set at 20℃, and injection volume was 20 μL. The detection wavelength was set at 230 nm (liquiritin, linquiritigenin, and sodium benzoata), 254 nm (glycyrrhizic acid and cinnamic alcohol), 276 nm (coumarin, cinnamic acid, and cinnamaldehyde), and 370 nm (isoliquiritin and isolinquiritigenin). Results With the extension of decocting time, the content of 10 components had maximum at 30 min and tended to be stable. The content of each component in Cinnamomi Ramulus firstly increased to the highest levels at 30 min and then decreased. And content of each component in Glycyrrhizae Radix basically showed an upward trend except at 40 minutes. Conclusion The optimized decocting time of Guizhi Gancao Decoction is confirmed for 30 min, which provids a scientific basis to its clinical application.

北京中医药大学在读研究生项目（2016-JYB-XS103）