Tylosema esculentum extractives and their bioactivity

• Published in: Bioorganic & medicinal chemistry 2011-09, Vol.19 (17), p.5225-5230
• Main Authors: Mazimba, Ofentse, Majinda, Runner R.T., Modibedi, Ceciliah, Masesane, Ishmael B., Cencič, Avrelija, Chingwaru, Walter
• Format: Article
• Language: English
• Subjects: Anti-Infective Agents - chemistry; Anti-Infective Agents - isolation & purification; Anti-Infective Agents - toxicity; Antimicrobial; Antineoplastic Agents, Phytogenic - chemistry; Antineoplastic Agents, Phytogenic - isolation & purification; Antineoplastic Agents, Phytogenic - toxicity; Antioxidant; Bacillus subtilis; beans; beta-sitosterol; Biological and medical sciences; Candida albicans; Cell Line, Tumor; cotyledons; Cytotoxicity; Escherichia coli; ethyl acetate; Fabaceae - chemistry; Fatty acids; free radical scavengers; Free Radical Scavengers - chemistry; Free Radical Scavengers - isolation & purification; Free Radical Scavengers - toxicity; gallic acid; gas chromatography; General pharmacology; hexane; hulls; Humans; inhibitory concentration 50; kaempferol; Magnetic Resonance Spectroscopy; mass spectrometry; Medical sciences; Microbial Sensitivity Tests; Molecular Conformation; nuclear magnetic resonance spectroscopy; oleic acid; Pharmacognosy. Homeopathy. Health food; Pharmacology. Drug treatments; plant extracts; Plant Extracts - chemistry; Plant Extracts - toxicity; protocatechuic acid; Pseudomonas aeruginosa; Spectrometry, Mass, Electrospray Ionization; Staphylococcus aureus; sucrose; Tylosema esculentum
• ISSN: 0968-0896; 1464-3391
• DOI: 10.1016/j.bmc.2011.07.006

The investigation of Tylosema esculentum (Morama) husks, cotyledons, and tuber yielded griffonilide 2, compound 1, griffonin 3, gallic acid 4, protocatechuic acid 5, β-sitosterol 6, behenic acid 7, oleic acid 8, sucrose 9, 2-O-ethyl-α-d-glucopyranoside 10, kaempferol 11 and kaempferol-3-O-β-d-glucopyranoside 12. The structures of the isolates were determined by NMR, HR-TOF EIMS, IR and UV–vis spectroscopy, and by comparison with literature data. The husk EtOAc and n-butanol extracts demonstrated >90% DPPH radical scavenging activity at concentrations of 25, 50 and 250μg/mL. Furthermore the husk extracts showed higher total phenolic content (233mg GAE/g). The extractives exhibited minimum inhibitory quantities of 50–100μg or no activity against Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa and Candida albicans. The tuber extracts were inactive against Caco-2 and Hela cell lines, while the husk extracts showed low activity against Caco-2 and Vero cell line with IC50 values >400μg/mL. The GC–MS analysis showed the beans and tuber non-polar (n-hexane) extracts major constituents as fatty acids.