DPP4 and type 2 diabetes mellitus: Whereby, the inhibition activity by the fruit extracts is probably due to the berberis compound that was present in the extract, where the activity of berberis is quite similar to DPP (IV) inhibitor, benzoquinolizines and it was demonstrated berberine significantly reduced the fasting blood glucose (FBG), lowered blood glucose level through increasing insulin receptor expression in T2DM.28