Nicotinamide metabolism in ferns: Formation of nicotinic acid glucoside

► [14C]Nicotinamide metabolism was investigated in fern species for the first time. ► Most nicotinamide was converted to nicotinic acid and was utilised to synthesise nicotinic acid glucoside. ► Some nicotinamide was metabolised by the pyridine nucleotide cycle, to generate NAD and NADP.