Anti-melanogenic activity of Suaeda maritima extract in α-MSH-stimulated B16F10 murine melanoma cells

Coastal salt marshes support Suaeda maritima (common sea-blite), yet the relevance of this halophyte to pigment biology is largely unknown. We tested its crude extract in B16F10 murine melanoma cultures in which melanogenesis had been induced with α-melanocyte-stimulating hormone (α-MSH). Two acellular readouts, mushroom tyrosinase inhibition and L-DOPA oxidation, were considered alongside cellular tyrosinase activity and melanin recovered from the medium and cell fraction. Melanogenic transcripts and their protein products were followed by RT-qPCR and immunoblotting. The extract suppressed both enzyme-based reactions. It also attenuated the α-MSH response in B16F10 cultures, as indicated by lower cellular tyrosinase activity and less melanin in both compartments. MITF, tyrosinase, and TRP-1 declined at the transcript and protein levels. MAPK analysis identified enhanced ERK phosphorylation, whereas phosphorylation of p38 and JNK diminished. These observations support two complementary actions: direct interference with tyrosinase-dependent chemistry and modulation of the MAPK/MITF program. S. maritima therefore merits investigation as a source of depigmenting cosmetic ingredients.