A process for preparing an extract of Momordica charantia, including: a) preparing crude juice b) filtering to obtain filtered juice c) modifying pH d) allowing the pH modified juice to stabilize e) neutralizing the stabilized juice f) allowing the neutralized juice to stand for 20-30 minutes g) rechecking the pH level and h) drying the juice to obtain the extract. The process said above is simple, cost effective, which does not employ any harmful organic solvents and which enhances the potency of the constituents. A simple and potent formulation showing anti-diabetic activity comprising active constituents of Momordica charantia is also provided.