RESUMO
AbstractPassiflora 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.
RESUMO
Pothomorphe umbellata is a native plant widely employed in the Brazilian popular medicine. This plant has been shown to exert a potent antioxidant activity on the skin and to delay the onset and reduce the incidence of UVB-induced skin damage and photoaging. The aim of this work was to optimize the appearance, the centrifuge stability and the permeation of emulsions containing P. umbellata (0.1% 4-nerolidylchatecol). Experimental design was used to study ternary mixtures models with constraints and graphical representation by phase diagrams. The constraints reduce the possible experimental domain, and for this reason, this methodology offers the maximum information while requiring the minimum investment. The results showed that the appearance follows a linear model, and that the aqueous phase was the principal factor affecting the appearance; the centrifuge stability parameter followed a mathematic quadratic model and the interactions between factors produced the most stable emulsions; skin permeation was improved by the oil phase, following a linear model generated by data analysis. We propose as optimized P. umbellata formulation: 68.4% aqueous phase, 26.6% oil phase and 5.0% of self-emulsifying phase. This formulation displayed an acceptable compromise between factors and responses investigated.
