Cholinesterase inhibition assays

Anti-cholinesterase potentials of selected essentials oils were evaluated by some modification of the spectrophotometric analysis respectively followed by [39]. Different dilutions of plant fraction were made ranging from (1000 to 62.5 μg/ml). Briefly, 10 μl each of acetylcholinesterase and butyrylcholinesterase 0.03 U/ml solution were mixed with 410 μL of different essential oils samples taken in a cuvette. Subsequently, DTNB solution (10 μL) was transferred to the mixture solution, mixed well and incubated at 30°C for 15 min. To start enzymatic reaction, 10μL substrates were added to the reaction mixture. Absorbance's were recorded at 412 nm via microplate reader.

Percent inhibition of AChE and BChE were evaluated by judgment of rates of reaction of tests samples comparative to that of control. Reaction mixture containing all substances without tested sample was used as control. All experiments were repeated three times. Galantamine, the anti-cholinesterase kind of drug was used as standard. The percent inhibition and percent enzymatic potential were calculated as follows;