Forty µL of plant extracts at concentrations of 200, 20, 2, 0.2 and 0.02 µg/mL were mixed with 50 µL of 3 mM DTNB, 50 µL of AChE (1 mg/mL, Sigma, C3389, Irvine, UK) or rat brain homogenate (prepared at 10% (w/v) according to references [55,56], and 35 µ...