Evaluation of the potential prebiotic effect of Himanthalia elongata, an Atlantic brown seaweed, in an in vitro model of the human distal colon

•The prebiotic effect of a whole brown seaweed has been studied for the first time.•Himanthalia elongata was mainly used by Bacteroides species.•Inulin was selectively used by the specie Parabacteroides distasonis.•Selective use of Parabacteroides distasonis by inulin has been reported by the firt time.•No differences between substrates for the metabolic pathways were found.