The development of drugs to treat Alzheimer disease has focused on strategies that enhance central cholinergic
function. Some herbal plants, which have fewer adverse effects and are less expensive than other medications, are
attractive drug candidates for a variety of diseases. In this study we tested the ability of extracts from ~100 plants to
inhibit the enzyme acetylcholinesterase. Among the plants, Levisticum officinale, Berberis integerrima, and Rheum
ribes inhibited the enzyme. We identified the active inhibitory compounds of these plants using thin-layer
chromatography (TLC) bioautography. Our results suggest that alkaloid and terpenoid compounds are primarily
responsible for the inhibitory activity of these plants. More research is needed to detect all of the compounds and
chemical structures that make up these plants
