Phenolic compounds from three brown seaweed species using LC-DAD-ESI-MS/MS

- The phenolic compound profiles of three brown seaweed extracts were evaluated.
- Ascophyllum nodosum, Bifurcaria bifurcata and Fucus vesiculosus seaweeds were studied.
- Phlorotannins was the major group of phenolic compounds in the three extracts.
- Phenolic acids were also present in the extracts from the three seaweed species.
- Flavonoids (mainly acacetin derivatives) were the third group of phenolics present.

The phenolic compounds of extracts from Ascophyllum nodosum (ANE), Bifurcaria bifurcata (BBE) and Fucus vesiculosus (FVE) from Galicia (NW Spain) were analyzed by liquid chromatography-diode array detection coupled to negative electrospray ionization-tandem mass spectrometry (LC-DAD-ESI-MS/MS) with the interest to evaluate their potential application as functional ingredients. Phlorotannins were tentatively identified as the main phenolic compounds in the three extracts, followed by phenolic acids, and flavonoids. Fuhalols were present in ANE and BBE, while hydroxyfuhalols were identified in BBE and FVE. Eckol derivatives were present in the three extracts. Quinic acid derivatives were tentatively identified in the three seaweed species; in addition, ANE showed specifically hydroxybenzoic and rosmarinic acid derivatives, BBE showed rosmarinic acid, and FVE contained p-coumaric and ferulic acid derivatives. Regarding flavonoids, acacetin derivatives were tentatively identified in the three extracts, hispidulin and a gallocatechin derivative were specifically detected in ANE, and cypellocarpin C was present in BBE. In conclusion, all brown seaweed extracts studied could be exploited as sources of antioxidant phenolic compounds with potential applications in the food and health sectors.