Antioxidant and antimicrobial activities of aporphinoids and other alkaloids from the bark of Annona salzmannii A. DC. (Annonaceae)

The antioxidant capacity by oxygen radical absorbance capacity (ORAC)-FL method and antimicrobial activity using the broth microdilution method of aporphinoids (liriodenine 1, anonaine 2 and asimilobine 3) and other alkaloids (reticuline 4 and cleistopholine 5) isolated from the bark of Annona salzmannii A. DC. (Annonaceae) were evaluated. For antioxidant activity, the most active alkaloid was asimilobine with ORAC value of 2.09 relative trolox equivalents. For antimicrobial activity, some alkaloids showed significant minimal inhibitory concentration (MIC) values in the range of 25-100 mu gmL(-1). The most active compounds were the aporphinoids liriodenine, anonaine and asimilobine, some of them more active than the positive control.