Effect of naringin enzymatic hydrolysis towards naringenin on the anti-inflammatory activity of both compounds

The aim of this work was the hydrolysis of naringin towards naringenin with immobilized naringinase and the evaluation of their anti-inflammatory activity. An acute local inflammation model (rat paw edema induced by λ-carrageenan) was chosen to evaluate the contribution of antioxidant properties to a possible anti-inflammatory effect.Grapefruit juice was processed with naringinase immobilized in k-carrageenan (2%) beads (≈ 3 mm). A 95% naringin conversion in grapefruit juice was obtained with immobilized naringinase (1000 mg L−1), with an activity of 19.5 mg mL−1 min−1 and the formation of 215 mg L−1 of naringenin.Ascorbic acid and indometacine were used as positive anti-inflammatory controls. All results were analysed using ANOVA with Dunnett's post-test. The results show that rats (n = 9) pre-treated with a solution of naringin, rats (n = 9) pre-treated with a solution of naringenin (in concentrations equal as in grapefruit juice) and rats (n = 9) treated with a solution of naringenin and naringin, revealed a significant reduction on edema formation, 6 h after λ-carrageenan injection. Naringenin demonstrated a high in vivo anti-inflammatory activity, only 8% of paw edema (p < 0.001) was observed in rats pre-treated with a solution of naringenin.Comparability studies, in rats administered orally with grapefruit juice (before and after processing), showed that enzymatic processing did not affect the anti-inflammatory properties of the juice.