Abstract:Identification of di-caffeoylquinic acids (di-CQAs) from Artemisia selengensis Turcz leaves and structure-activity relationship of di-CQAs on inhibiting xanthine oxidase (XOD) and inhibiting monosodium urate (MSU) induced IL-1β in vitro were studied. Di-CQAs from Artemisia selengensis Turcz leaves were identified by HPLC-Q/TOF-MS, and the effects of different di-CQAs on inhibiting XOD and inhibiting monosodium urate induced IL-1β were systematically studied. Results showed that five di-CQAs (1,4-diCQA, 3,4-diCQA, 1,5-diCQA, 3,5-diCQA and 4,5-diCQA) were identified in Artemisia selengensis Turcz leaves, and 1,4-diCQA was identified in Artemisia selengensis Turcz leaves in this study for the first time. The XOD inhibitory activity of caffeic acid substitution sites on di-CQAs was ranked as follows: C1 substitution > C4 substitution > C5 substitution > C3 substitution; The MSU-inducedIL-1β inhibitory activity of caffeic acid substitution sites on di-CQAs was ranked as follows: C1 substitution > C5 substitution > C3 substitution, C4 substitution≥ C5 substitution. In addition, the XOD inhibitory activity of di-CQAs was positively correlated with the MSU-induced IL-1β inhibitory activity of them, suggesting that di-CQAs couldinhibit MSU-induced IL-1β via inhibiting XOD. This study provides theoretical basis for studying the biological activities of di-CQAs with different structures, and also gives a reference for the development of di-CQAs from Artemisia selengensis Turcz and other dietary food for the prevention of hyperuricemia and gout.