QPCT and Alzheimer disease: In particular, sulfolipids extracted from the green microalgae (Chlorophyta) Tetradesmus lagerheimii (formerly Scenedesmus acuminatus), Scenedesmus producto-capitatus, Pectinodesmus pectinatus (formerly Scenedesmus pectinatus), and Tetradesmus wisconsinensis were able to inhibit glutaminyl cyclase (QC) [133], an enzyme involved in Alzheimer’s disease progression [152] and were suggested as possible lead compounds against Alzheimer’s disease.