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目的：研究白杨素分别与人重组酶SULT1A3和人小肠S9（human small intestine S9，HSI S9）孵育体系磺酸化结合反应的代谢特性。方法采用高效液相色谱法，测定白杨素及其代谢产物，并应用LC-MS／MS液质联用技术鉴定其结构。分别建立白杨素与重组酶SULT1A3及与人小肠S9的反应体系，测定不同浓度的白杨素在不同酶反应中的代谢速率。结果白杨素与SULT1A3及人小肠S9孵育体系反应的代谢产物均为单磺酸化结合产物。白杨素与重组酶SULT1A3及人小肠S9的酶反应均呈双相动力学特征。白杨素与SULT1A3酶反应的动力学参数Km为（3.06±1.04）、（0.41±0.06）μM，Vmax为（12.13±1.30）、（6.72±1.61） nmol／（min· mg），Vmax／Km为3.96、16.39 mL／（min· mg）。白杨素与人小肠S9的酶反应的动力学参数Km为（1.92±0.35）、（0.01±0.00）μM，Vmax为（0.52±0.02）、（0.08±0.02）nmol／（min· mg），Vmax／Km为0.27、8.00 mL／（min· mg）。重组酶SULT1A3和人小肠S9分别介导的白杨素磺酸化结合反应的代谢呈现显著的相关性（ R2＝0.985）。结论 SULT1A3在白杨素的肠道代谢中发挥主导作用，小肠可能是白杨素的主要代谢器官。“,”Objective To investigate the metabolic profile of chrysin in SULT1A3 and human small intestine S9.Methods After incubation of chrysin using in vitro SULT1A3 and human small intestine S9 system, high-performance liquid chromatography was utilized to determine the sulfates of chrysin.Mass spectrum(MS) were employed to elucidate the structures of metabolite.Results In the SULT1A3 with PAPS, Km were (3.06 ±1.04) and (0.41±0.06) μM, Vmax were (12.13 ±1.30) and (6.72 ±1.61) nmol/(min· mg), Vmax/Km were 3.96 and 16.39 mL/(min· mg), respectively.In the human small intestine S9 with PAPS, Km were (1.92 ±0.35) and (0.01 ±0.00) μM, Vmax were (0.52 ±0.02) and (0.08 ± 0.02) nmol/(min· mg), Vmax/Km were 0.27 and 8.00 mL/(min· mg).The metabolic behavior of chrysin in SULT1A3 and human small intestine S9 both were followed biphasic kinetics.The sulfation of chrysin in SULT1A3 showed a significant correlation with that in human small intestine S9(R2 =0.985).Conclusion The result indicates that SULT1A3 is the major enzyme to the metabolism of chrysin, human small intestine may be the main metabolic organs of chrysin.