In our previous work concerning natural anti-Alzheimer’s disease (anti-AD) drugs from marine sources [11,12], eckol from Ecklonia stolonifera showed selective inhibition of acetylcholinesterase (AChE) and β-site amyloid precursor protein-cleaving enzyme 1 (BACE1), but not butyrylcholinesterase (BChE). Here, ACHE is linked to Alzheimer disease.