Antioxidant and Anti-inflammatory Meroterpenoids from the Brown Alga Cystoseira usneoides

Abstract

A chemical study of the alga Cystoseira usneoides has led to the isolation of six new meroterpenoids, cystodiones A-F (1-6), together with six known related compounds (7-12). The structures of the new metabolites have been established by spectroscopic techniques. In antioxidant assays all of the tested meroterpenes, and in particular cystodiones A (1) and B (2), 6-cis-amentadione-1'-methyl ether (7), and amentadione-1'-methyl ether (8), exhibited strong radical-scavenging activity. In anti-inflammatory assays, usneoidone Z (11) and its corresponding 6E isomer (12) showed significant activity as inhibitors of the production of the proinflammatory cytokine TNF-α in LPS-stimulated THP-1 human macrophages.

Screening of antimicrobial activity of macroalgae extracts from the Moroccan Atlantic coast

“…Bifurcaria bifurcata B + ++ +++ ++ C --++ + activities of brown algae are confirmed by several studies [14][15][16][17][18].…”

“…The Cystoseira genus is widely studied for its chemical composition and biological activities [15][16][17][18]36,51].…”

The Algal Meroterpene 11-Hydroxy-1′-O-Methylamentadione Ameloriates Dextran Sulfate Sodium-Induced Colitis in Mice

“…Although most research on the pharmacological potential of algal natural products has focused on cytotoxic and antimicrobial activities [8,9,11], recent studies are also disclosing interesting properties of algae-derived extracts and natural products as anti-inflammatory agents [12,13,14,15]. Thus, we have recently described the in vitro anti-inflammatory activity of a series of meroterpenoids isolated from the brown alga Cystoseira usneoides [16,17]. In particular, the meroditerpene 11-hydroxy-1′- O -methylamentadione (AMT-E) (Figure 1), which is one of the major natural products of this alga, showed significant activity as an inhibitor of the production of the pro-inflammatory cytokine TNF-α in LPS-stimulated THP-1 human macrophages [16].…”

“…Thus, we have recently described the in vitro anti-inflammatory activity of a series of meroterpenoids isolated from the brown alga Cystoseira usneoides [16,17]. In particular, the meroditerpene 11-hydroxy-1′- O -methylamentadione (AMT-E) (Figure 1), which is one of the major natural products of this alga, showed significant activity as an inhibitor of the production of the pro-inflammatory cytokine TNF-α in LPS-stimulated THP-1 human macrophages [16]. …”

Photodamage attenuation effect by a tetraprenyltoluquinol chromane meroterpenoid isolated from Sargassum muticum

“…Meroterpenoids from Cystoseira and Sargassum sp. exhibited strong radical scavenging activity, protection against UV-irradiation [5,6], inhibition of lipid peroxidation and O 2 À [28], antifouling [29] and antiinflammatory properties [30].…”