Study on anti-inflammatory activities of phenolic acids from Lonicerae Japonicae Flos / 中草药

ABSTRACT

Objective: To study the anti-inflammatory of phenolic acids from Lonicerae Japonicae Flos. Methods: The compounds in the EtOAc fraction were isolated and purified by silica gel and Sephadex LH-20 column chromatographies, and preparative HPLC as well. The structures were identified by various spectroscopic data such as ESI-MS, 1H-NMR, and 13C-NMR data. The anti-inflammatory effects were evaluated by a in vitro model of LPS-stimulated RAW264.7 macrophages. Results: Eight phenolic acids, three iridoids, and one flavonoid were isolated from the extracts of Lonicerae Japonicae Flos and identified as 5-O- caffeoylquinic acid (1), 4-O-caffeoylquinic acid (2), 3,5-di-O-caffeoylquinic acid (3), 3,4-di-O-caffeoylquinic acid (4), 4,5-di-O- caffeoylquinic acid (5), chlorogenic acid (6), caffeic acid (7), methyl caffeate acid (8), secoxyloganin (9), secologanoside (10), sweroside (11), and luteolin (12). Compounds 1-8 showed the anti-inflammatory activity in different degrees. Conclusion: Phenolic acids are the main anti-inflammatory constituents in Lonicerae Japonicae Flos. Caffeic acid shows the strongest activity in vitro.