de los Reyes, Carolina , Ortega, Maria J. , RODRÍGUEZ LUNA, AZAHARA MARÍA, Talero, Elena , Motilva, Virginia , Zubia, Eva
No
J. Agric. Food Chem.
Article
Científica
3.154
1.305
23/11/2016
000388913400009
Isochrysis galbana is a marine microalga rich in PUFAs that is widely used as feed in aquaculture and more recently investigated for its potential in food applications and as source of bioactive compounds. In this study, the biomass obtained from cultures of I. galbana has been investigated to determine its content in glycosylglycerides and glycosylceramides. By using NMR, UPLC-MS/MS, and fatty acid profiles, the structures of ten monogalactosyldiacylglycerols (MGDGs 1-10) and nine digalactosyldiacylglycerols (DGDGs 11-19) have been established. Two distinctive features of the galactosylglycerides from I. galbana are the wide presence of highly unsaturated aryl chains derived from stearidonic acid (18:4 Delta(6z,9z,12z,15z)) and octadecapentaenoic acid (18:5 Delta(3z,6z,9z,12z,15z)) as well as the unusual coexistence of alpha beta-DGDGs and beta beta-DGDGs. Three new galactosylceramides, isogalbamides A-C (20-22), have also been isolated and characterized by NMR and MS/MS. These metabolites, which are the first galactosylceramides described from microalgae, derive from unprecedented tetraolefinic sphingoid bases. In anti-inflammatory assays, the MGDG and DGDG mixtures and the isolated DGDGs 11 and 12 showed significant activity as inhibitors of the production of the pro -inflammatory cytokine TNF-alpha in lipopolysaccharide-stimulated human THP-1 macrophages, while the galactosylceramides showed moderated activity.
microalgae; Isochrysis galbana; galactosylglycerides; MGDG; DGDG; galactosylceramides; anti-inflammatory activity; TNF-alpha inhibition