LC/PDA/ESI-MS/MS Chemical profiling, radical scavenging and antibacterial activities of two Abutilon spp. native to Sudan

• Published in: Planta medica
• Main Authors: Ali, HA, Elamin, MH, Kim, JB, Cho, KJ, Ki, C, Khalid, SA
• Format: Conference Proceeding
• Language: English
• Published: 21.07.2009
• ISSN: 0032-0943; 1439-0221
• DOI: 10.1055/s-0029-1234989

The present communication represents the first attempt to subject Abutilon pannosum Forst. f. Schlecht. and A. figarianum Webb (Malvaceae) to bioactivity-directed fractionation in order to detect their bioactivities and the profile of the secondary metabolites associated with these activities. Dried flowers were extracted separately by petroleum ether, chloroform and 80% methanol. The extracts were tested against two gram positive and three gram negative human pathogenic bacteria. The chloroform extracts of A. figarianum and A. pannosum exhibited inhibitory activity against Bacillus subtillus of 18mm and 16mm, at a concentration of 1mg/ml, respectively. Meanwhile, higher concentration (5mg/ml) of the methanolic extract of both A. figarianum and A. pannosum exhibited significant inhibitory activity against Bacillus subtillus (80%, 76%), Escherichia coli (52%, 60%), Pseudomonas aeruginosa (70%, 80%), Staphylococcus aureus (70%, 60%) and Proteus vulgaris (80%, 70%), respectively. The aqueous residue of the methanolic extract was further partitioned with ethyl acetate and n -butanol. The ethyl acetate fractions of both plants possessed a prominent antioxidant activity (80% inhibition) at a concentration of 1mg/ml using DPPH (1,1-diphenyl-2-picrylhydrazyle) as a free radical source. The chemical structures of the compounds present in the bioactive extracts and their respective fractions were elucidated by tandem mass spectrometry (HPLC-MS/MS-ESI) leading to the identification of 18 compounds: 13 flavonols, 3 flavones, 1 flavanons and 2 anthocyanins derivatives. A number of reports of the antioxidant and antimicrobial activities of other Abutilon species have already been published [1,2]. References: [1] Porchezhian, E., and Ansari, S.H. (2005) Phytomedicine 12:62–64. [2] Matlawska, I. and Sikorska, M. (2005) Acta Pol. Pharm. Drug Res. 62:135–139.