Bioassay-guided isolation of antifungal alkaloids from Melochia odorata.

An alkaloidal extract of the leaves of Melochia odorata exhibited antifungal activity against Candida albicans, Cryptococcus neoformans and Saccharomyces cerevisiae using a TLC bioautographic method. Bioassay-guided fractionation of this extract using separation by normal and reverse high-performance liquid chromatography (HPLC) resulted in the isolation of two active compounds identified as frangulanine, a cyclic peptide alkaloid, and waltherione-A, a quinolinone alkaloid.