High-performance thin-layer chromatography marker-based standardization of Piperine, Asiaticoside, and Withanolide-A in the developed polyherbal formulation and in vitro evaluation of acetylcholinesterase inhibition Pai V, Chandrashekar KS, Rao PPicheshwar, Setty MManjunath. High-performance thin-layer chromatography marker-based standardization of Piperine, Asiaticoside, and Withanolide-A in the developed polyherbal formulation and in vitro evaluation of acetylcholinesterase inhibition. Pharmacognosy Magazine . 2019;15(64): 256-260.