Fig. 2

Effect of test compound(s) on acetylcholinesterase activity and acetylcholine levels. Acetylcholine (ACh) levels (blue bars), acetylcholinesterase (AChE) inhibitory activity (red bars), and acetylcholinesterase enzyme activity (green bars) in 168 hpf larvae unexposed to any test compound (i.e. ‘untreated’), treated with scopolamine (SCOP), isoxazole (ISOX), Convolvulus pluricaulis (CP) and their combinations (ISOX + SCOP, CP + SCOP, and CP + ISOX) have been shown. Both the ACh level (µM) and AChE activity (%) have been expressed as mean ± standard deviation. Three independent experiments were conducted to determine ACh level and AChE activity, and in each of these experiments, three sets of 15–25 embryos were treated with the least toxic concentrations of SCOP (6.68 μM), ISOX (1.04 mM), and CP (0.38 mg/ml) and their combinations. The larvae were treated with the AChE inhibitor (i.e. ISOX or CP) one hour before treatment with SCOP. *, **, and *** indicate p-value < 0.5, < 0.01 and < 0.001 of two-tailed unpaired t-test for untreated versus test groups respectively