ACHE and Alzheimer disease: The search for new drugs, such as Huperzin A, with acetylcholinesterase inhibitory activity to be used in the treatment of AD from natural resources, also yielded some herbal-originated extracts and/or compounds such as Ginkgo biloba, Panax ginseng, Davilla rugosa, (-)-epigallocatechin, ferulic acid, etc. which act by different mechanisms.[25–28] However, acetylcholinesterase inhibitors have been accepted to be the most effective for the treatment of AD, to date.