Antifungal diacetyglycerols from Malachra fasciata and Pithecolobium dulce

Extracts of Malachra fasciata and Pithecolobium dulce (Roxb.) Benth afforded a mixture of 1,2- and 1,3-diacetylglycerol. Kaempferol-3-0-a-L-rhamnopyranoside, lutein f3-carotene, spinasterol, dodecaprenol, and tridecaprenol were also isolated from P. dulce. The structures of the diacetylglycerols and the glycoside were elucidated by 1D and 2D NMR analyses. The structures of the decaprenols were deduced from mass spectral data, while the other compounds were identified by comparison with the IH NMR data in the literature. The diacetylglycerols indicated high antifungal activity against Aspergillus niger, moderate activity against Pseudomonas aeruginosa and Candida albicans and slight activity against Bacillus subtilis, Escherichia coli, and Trichophyton mentagrophytes. It was inactive against Staphylococcus aureue. Kaempferol-3-0-a-Lrhamnopyranoside was moderately active against the fungus, C. albicans, and has slight activity against the fungi A. niger, T. mentagrophytes, and the bacteria E. coli and P. aeruginosa. It was inactive against the bacteria, S. aureus and B. subtilis.