Each participant took the following interventions in randomized order, with a washout period of 7 days between the interventions:

100 milligrams of the mango leaf extract (containing 60 mg of mangiferin, a compound with antioxidant properties)
150 milligrams of the mango leaf extract (containing 90 mg of mangiferin)
A placebo

The researchers assessed cognitive function and mood before supplementation, as well as 30 minutes, 3 hours, and 5 hours after supplementation.

Supplementation with the mango leaf extract improved aspects of cognitive function (including attention, cognitive flexibility, cognitive speed, executive function, and working memory) and mood (including confusion and tension), compared with the placebo.

The trial was funded by Nektium Pharma S.L., the manufacturer of the mango leaf extract, and several of the researchers were employees of the company during the trial.

Can a mango leaf extract improve cognition and mood in university students? Original paper