Cymopolia barbata (Linnaeus, 1758) J. V. Lamouroux, 1816

Kurth, Caroline, Welling, Matthew & Pohnert, Georg, 2015, Sulfated phenolic acids from Dasycladales siphonous green algae, Phytochemistry 117, pp. 417-423 : 418

2.2. Sulfated metabolites of C. barbata

In C. barbata chromatograms two dominant signals exhibiting an [M–H–80] – fragment were observed. Retention times and mass spectra were in accordance with dihydroxycoumarin sulfate and SBA. Co-injection experiments as described above proved these structural suggestions ( Fig. 3 ). In the extracts of slightly stressed algae we could still detect the ions corresponding to SBA and dihydroxycoumarin sulfate. We also found trihydroxycoumarin indicative for a wound activated desulfatation, a mechanism previously shown to control wound plug formation of D. vermicularis ( Fig. 1 ) ( Welling et al., 2011). In addition in non-stressed algal material extracted directly after harvesting we observed a signal with a molecular ion of 289 [M–H] – (data not shown) that also exhibited the loss of 80, which would be in accordance with a methoxylated dihydroxycoumarin sulfate.

Figures

Fig. 3. LC/MS chromatograms of (A) a C. barbata extract, the labeled peak indicates dihydroxycoumarin sulfate (DHyCS). (B) Co-injection with 4-(sulfooxy)benzoic acid (SBA) in ESI-negative ionization mode.

Fig. 1. Structures and transformation of the sulfated aromatic metabolites from Dascycladales.