Antifungal flavones from Waltheria americana

• Main Author: Cruz, Carmel A.
• Format: text
• Language: English
• Published: Animo Repository 1996
• Subjects: Antifungal agents; Flavonoids > Spectra; Microbial sensitivity tests; Solution (Chemistry); Medicinal plants; Sterculiaceae; Chemistry
• Online Access: https://animorepository.dlsu.edu.ph/etd_masteral/1727; https://animorepository.dlsu.edu.ph/cgi/viewcontent.cgi?article=8565&context=etd_masteral
• Institution: De La Salle University

Walteria americana [common name: Barulad (Ilocano), Kanding-kanding (Negros Occidental)] belongs to the family Sterculiaceae. Walteria americana afforded two flavones, 5,2,5,' trihydroxy-3,7,4' trimethoxy flavone and 5,2' dihydroxy-3,7,4',5' tetramethoxyflavone. The structure of the first compound was elucidated by Hydrogen-1-nuclear magnetic resonance (1H-NMR), Carbon-13-nuclear magnetic resonance (13C-NMR), 1H Detected Heteronuclear Multibond (long-range) Shift Correlation (HMBC), Heteronuclear Multiquantum Coherence (HMQC), Nuclear Overhausser Effect Spectroscopy (NOESY), D2O Exchange and Mass Spectrometry. This was further confirmed by Chemwindow 13C shift prediction. The identity of the second isolate was determined by comparison of its 1H-NMR, 13C-NMR and Mass Spectrum with that of the first compound.Both flavones are exclusively very active against the fungal microorganisms, Aspergillus niger, Candida albicans and Trichophyton mentagrophytes but inactive when tested against gram (+) positive and gram (-) negative, Salmonella typhi, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus.