Identification and large isolation of an anti-inflammatory compound from an edible brown seaweed, Undariopsis peterseniana, and evaluation on its anti-inflammatory effect in in vitro and in vivo zebrafish

Abstract

In this study, we isolated and purified secondary metabolites from an edible brown seaweed, Undariopsis peterseniana, and evaluated their anti-inflammatory effects in vitro and in vivo. Apo-9'-fucoxanthinone (Apo-9'), a main anti-inflammatory compound found in the chloroform fraction of U. peterseniana extracts, was first isolated by one-step centrifugal partition chromatography and identified by nuclear magnetic resonance. Apo-9' significantly decreased nitric oxide (NO), prostaglandin E-2, pro-inflammatory proteins (inducible NO synthase [iNOS] and cyclooxygenase [COX-2]), and pro-inflammatory cytokines (tumor necrosis factor-alpha, interleukin-6, and interleukin-1 beta) in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells without exhibiting any cytotoxicity. In vivo, Apo-9' protected LPS-stimulated zebrafish embryos against inflammatory stress and suppressed the expression of pro-inflammatory proteins such as COX-2 and iNOS. These findings suggest that U. peterseniana extract and Apo-9' could be used as an anti-inflammatory agent in health care.