Evaluation of gastroprotective activity of Passiflora alata

Passiflora alata Curtis, Passifloraceae, is a liana popularly known in Brazil as ‘maracujá-doce’ that has been used for treating different illnesses. Its leaves are described in the Brazilian Pharmacopoeia, but the gastroprotective activity has never been investigated. In the present study a freeze-dried crude 60% ethanol–water extract of P. alata aerial parts was prepared. Total flavonoid content, expressed as vitexin, was 0.67% ± 0.01. The hemolytic activity was 32 units for P. alata, using Saponin (Merck®) as reference. P. alata presented EC50 of 1061.2 ± 8.5 µg/ml in the 2,2-diphenyl-1-picryhydrazyl assay and 1076 ± 85 µmol Trolox/g in the Oxygen Radical Absorbance Capacity assay. P. alata, its solvent fractions and a P. alatananopreparation were investigated for gastroprotective activity. The test samples exhibited gastroprotective activity on HCl/ethanol induced gastric mucosal lesions in rats. P. alata at doses of 100, 200 and 400 mg/kg, using the necrotizing agent at 150 mmol/l, inhibited 100% of ulcer formation (compared to the negative control), while lansoprazole (30 mg/kg) 77%. When tested against a more concentrated necrotizing agent (300 mmol/l), fractions of P. alata at 100 mg/kg reduced 57% (n-hexane), 34% (ethyl acetate) and 72% (aqueous fraction) the ulcer formation. In this assay, lansoprazole (30 mg/kg) inhibited 47%. When encapsulated, P. alata inhibited ulcer formation at 55%, 94% and 90% for dosages of 25, 50 and 100 mg/kg. These results suggest the potential use of P. alata as a gastroprotective herbal medicine