Bioassay-guided isolation of anti-inflammatory C-glucosylflavones from Passiflora edulis

Passiflora edulis, commonly known as "maracujá", is widely cultivated in Brazil for the industrial production of juice. The species of Passiflora are popularly used as a sedative or tranquillizer, and also against intermittent fever and skin inflammation. In this study we evaluated the anti-inflammatory activity of four sub-fractions and three isolated compounds from the butanolic fraction of P. edulis var. flavicarpa leaves, using the mouse model of pleurisy induced by carrageenan. The butanolic fraction obtained from an aqueous extract of P. edulis (50 and 100 mg/kg, I. P.) showed anti-inflammatory activity by inhibiting leukocytes and neutrophils (p < 0.01). Sub-fraction C showed itself to be more effective than the other sub-fractions (p < 0.01). Isoorientin ( 1), vicenin-2 ( 2) and spinosin ( 3) were isolated from the active sub-fraction C derived from the butanolic fraction. The sub-fraction C (50 mg/kg, I. P.), as well as its major isolated compounds (25 mg/kg, I. P.), inhibited leukocytes and neutrophils (p < 0.05). Additionally, the butanolic fraction and isoorientin also inhibited myeloperoxidase activity (p < 0.05). The present study showed that the C-glucosylflavones isolated from P. edulis leaves can be responsible for the anti-inflammatory effect of P. edulis on the mouse model of pleurisy.