ACHE and Alzheimer disease: Dibenzo-1,4-dioxine-2,4,7,9-tetraol (IC50 84.48 ± 0.26 μM) and eckol (IC50 76.70 ± 0.35 μM) exhibited better inhibitory activity against AChE than phloroglucinol (IC50 579.32 ± 0.34 μM), suggesting that dibenzo-1,4-dioxine-2,4,7,9-tetraol and eckol could be effective as AChE inhibitors in treatment of AD [26].