Moreover, in order to calculate the binding affinities of inhibitors towards the protein target, the molecular mechanics-Poisson-Boltzmann surface area (MM PBSA) method was carried out. For this purpose, trajectories of the simulations were processed and last 5 ns simulation data with frame increment of 250 were selected for MM PBSA calculation. The result of this calculation showed that the reference compound famotidine exhibited negative binding energy of 19.88 ± 0.71 Kcal/mol, whereas alkaloid hits CNP0416047, 3-hydroxy anisotine and anisotine displayed comparable negetaive binding energies of 22.71 ± 0.70 Kcal/mol, 21.77 ± 0.68 Kcal/mol, and 31.38 ± 0.72 Kcal/mol respectively (Table ).