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Updated: Jan 22, 2026

Expression, Purification, and Antimicrobial Activity of S100A12
Published on: May 13, 2017
Caffeoylquinic acid derivatives (CQAs) from Daphne gemmata and their antimicrobial activities
Lin Li1,2, Fu-Qiang Song1,3, Ping-Jing Yu1
1School of Pharmaceutical Science and Yunnan Key Laboratory of Pharmacology of Natural Products, Kunming Medical University, Kunming, Yunnan, P. R. China.
Abstract:
One new caffeoylquinic acid derivative, daphnequinic acid (1), along with six known analogues (2-7), were isolated from Daphne gemmata. The new caffeoylquinic acid was elucidated through interpretation of comprehensive NMR spectral data, in combination with a quantum chemical calculations ECD analysis. Compounds 1-7 were evaluated for their antimicrobial activities against E. coli, S. aureus, S. enterica, and P. aeruginosa. The antibacterial activity assay demonstrated that compounds 3, 6, and 7 exhibited moderate antibacterial activity against S. aureus, with minimum inhibitory concentration (IC50) values of (41.97 ± 0.16) μM, (23.35 ± 0.32) μM, and (18.91 ± 1.55) μM, respectively.
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