A comprehensive search was performed in various databases, including Google Scholar, Web of Science, ScienceDirect, PubMed, Springer Link, and the Virtual Health Library, using a number of keywords and their combinations in English: Alzheimer’s disease, neurodegeneration, neuroprotection, meroterpenoids, fungi, marine sponge, mushroom, amyloid beta, tau, oxidative stress, and enzyme inhibition. The gene discussed is MAPT; the disease is Alzheimer disease.