Evidence of the gastroprotective and anti-helicobacter pylori activities of β-mangostin isolated from Cratoxylum arborescens (Vahl) blume nork Sidahmed, H.M.A., Hashim, N.M., Mohan, S., Abdelwahab, S.I., Taha, M.M.E., Dehghan, F., Yahayu, M., Ee, G.C.L., Loke, M.F., Vadivelu, J.