Antifungal and antibacterial naphthoquinones from Newbouldia laevis roots

• Published in: Phytochemistry (Oxford) Vol. 42; no. 5; pp. 1315 - 1320
• Main Authors: Gafner, Stefan, Wolfender, Jean-Luc, Nianga, Malo, Stoeckli-Evans, Helen, Hostettmann, Kurt
• Format: Journal Article
• Language: English
• Published: OXFORD Elsevier Ltd 01.07.1996; Elsevier
• Subjects: Anti-Bacterial Agents - chemistry; Anti-Bacterial Agents - isolation & purification; Antifungal Agents - chemistry; Antifungal Agents - isolation & purification; Biochemistry & Molecular Biology; Biological and medical sciences; Biotechnology; Chemical control; Control; Crystallography, X-Ray; Fundamental and applied biological sciences. Psychology; Fungal plant pathogens; General pharmacology; Life Sciences & Biomedicine; Medical sciences; Naphthoquinones - chemistry; Naphthoquinones - isolation & purification; Pharmacognosy. Homeopathy. Health food; Pharmacology. Drug treatments; Phytopathology. Animal pests. Plant and forest protection; Plant Sciences; Plants, Medicinal - chemistry; Science & Technology; Spectrum Analysis; Africa; antibacterial activity; naphthoquinones; Bignoniaceae; roots; Newbouldia laevis; antifungal activity; QUINONES; HIGHER-PLANTS; Candida albicans; Plant pathogen; Molecular structure; Bacillus subtilis; Escherichia coli; Extract; Cladosporium cucumerinum; Bacillaceae; Medicinal plant; Fungi; Antifungal agent; Bacillales; Folk medicine; Dicotyledones; Angiospermae; Chemical control; Bacteria; Fungi Imperfecti; Enterobacteriaceae; Thallophyta; Root; Pharmacognosy; Biological activity; Plant origin; Isolation; Spermatophyta; Antibacterial agent; Naphthoquinone
• ISSN: 0031-9422; 1873-3700
• DOI: 10.1016/0031-9422(96)00135-5

From a dichloromethane extract of Newbouldia laevis roots, four new (6-hydroxydehydroiso-α-lapachone, 7-hydroxydehydroiso-α-lapachone, 5,7-dihydroxydehydroiso-α-lapachone and 3-hydroxy-5-methoxydehydroiso-α-lapachone) and six known naphthoquinones have been isolated. Their structures were established by spectroscopic methods (UV, EI mass spectrometry, 1H and 13C NMR) and that of 7-hydroxydehydroiso-α-lapachone was confirmed by X-ray crystallography. All naphthoquinones showed antifungal activity against Cladosporium cucumerinum and Candida albicans, and activity against the bacteria Bacillus subtilis and Escherichia coli.