진귤 가지 추출물의 항염, 항산화 및 항균 활성 성분 연구

Abstract

In this study, we investigated bioactive constituents from Citrus sunki branches. Phytochemical investigation of the ethanol extract from C. sunki branches resulted in the isolation of four constituents; nobiletin (1), 6-demethoxytangeretin (2), 5,4'-dihydroxy-6,7,8,3'-tetramethoxyflavone (3) and hesperidin (4). The chemical structures of these compounds were elucidated based on the spectroscopic data including NMR spectra, as well as comparison of the data to literature values. As far as we know, compound 3 was isolated for the first time from this plant. For the anti-inflammatory activity tests using RAW264.7 murine macrophage cells, the EtOAc fraction and isolated compounds (1 and 3) inhibited nitric oxide (NO) production sinificantly. Also, EtOAc fraction and compound 3 showed inhibition activities on production of PGE2 and pro-inflammatory cytokines (TNF-α, IL-1β and IL-6). On the screening of anti-oxidative activities, the EtOAc fraction showed potent DPPH and ABTS+ radical scavenging activities. Moreover, the total phenolic contents and total flavonoid contents for the EtOAc fraction were estimated as 71.9 mg/g GAE and 79.9 mg/g QE, respectively. On the anti-bacterial activity studies of C. sunki , n-Hex and EtOAc fractions showed activities on S. aureus (CCARM 0027, 3707, 3708), S. epidermidis (CCARM 3709, 3711) and P. acnes (CCARM 9009). Based on these results, extract of C. sunki branches could be potentially applicable as anti-inflammatory, anti-oxidative and anti-bacterial ingredients.