Antioxidant Constituents from Xylopia championii.

AbstractXylopia championii. Hook. f. & Thoms. (Annonaceae) is endemic to Sri Lanka. The antioxidant and antifungal activities of five alkaloids, oxopurpureine, (+)-laudanidine, (−)-discretine, nordicentrine, and dehydrocorytenchine, isolated from the stem bark and stem of X. championii., were studied. The alkaloids, (+)-laudanidine and (−)-discretine, at a concentration of 0.5 mg/mL, exhibited exceptionally high antioxidant activity, where as nordicentrine and dehydrocorytenchine showed moderate activity as compared with the standard antioxidant dl-α -tocopherol in the DPPH assay. All five alkaloids were subjected to an antifungal bioassay against Clodosporium cladosporioides.. Nordicentrine showed the most potent antifungal activity at 6 μ g/spot, and (-)-discretine showed moderate activity at 30.0 μg/spot.