title: Antibacterial activity of the roots, stems and leaves of Alchornea floribunda.
abstract: BACKGROUND
  Alchornea floribunda Müll. Arg. is used in traditional medicine across Africa for the treatment of bacterial, fungal, parasitic and inflammatory disorders.
  
  
  OBJECTIVE
  To evaluate the antibacterial activity of the crude extracts of different plant parts in order to provide a scientific rationale for the proposed broad efficacy of Alchornea floribunda in the treatment of bacterial infections.
  
  
  METHODS
  Extracts of roots, stems and leaves were prepared using solvents of various polarities in order to extract a wide range of phytochemicals. The antibacterial activity of these crude extracts was evaluated by micro-dilution assay, against Gram-positive (i.e. Bacillus cereus, Enterococcus faecalis, Staphylococcus aureus and Staphylococcus saprophyticus) as well as Gram-negative (i.e. Escherichia coli, Klebsiella pneumoniae, Moraxella catarrhalis and Proteus mirabilis) bacteria.
  
  
  RESULTS
  Generally, the ethanol (EtOH), methanol (MeOH), ethyl acetate (EtOAc) and chloroform (CHCl3) extracts demonstrated the best activities, with the leaves exhibiting the highest average activity for six of the eight pathogens. Of these, the ethanolic leaf extract was the most active against Staphylococcus aureus with an MIC value of 50µg/mL. Some other notable activity was observed for the ethyl acetate and chloroform root extracts against Staphylococcus aureus (50µg/mL), and for selected stem extracts against Staphylococcus aureus (50µg/mL), Klebsiella pneumoniae (63µg/mL) and Staphylococcus saprophyticus (63µg/mL).
  
  
  CONCLUSIONS
  This study demonstrates the promising antibacterial activity of Alchornea floribunda against both Gram-positive and Gram-negative bacteria responsible for gastrointestinal, skin, respiratory and urinary ailments, and validates its use in the ethnopharmacology of the region.
authors: Department of Applied Chemistry, University of Johannesburg, PO Box 17011, Doornfontein, Johannesburg 2028, South Africa.
authors: X
authors: X
authors: Siwe Noundou
authors: Department of Chemistry, Rhodes University, Grahamstown 6140, South Africa. Electronic address: r.krause@ru.ac.za.
authors: R W M
authors: RW
authors: Krause
authors: Department of Pharmacy and Pharmacology, University of the Witwatersrand, 7 York Road, Parktown 2193, South Africa.
authors: S F
authors: SF
authors: van Vuuren
authors: Department of Chemistry, Rhodes University, Grahamstown 6140, South Africa.
authors: D
authors: D
authors: Tantoh Ndinteh
authors: School of Mining, Metallurgy and Chemical Engineering, University of Johannesburg, PO Box 17011, Doornfontein, Johannesburg 2028, South Africa.
authors: D K
authors: DK
authors: Olivier
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D019665:Euphorbiaceae; D006090:Gram-Negative Bacteria / Q000187:drug effects*; D006094:Gram-Positive Bacteria / Q000187:drug effects*; D016488:Medicine, African Traditional; D008826:Microbial Sensitivity Tests; D010936:Plant Extracts / Q000494:pharmacology*; D018515:Plant Leaves; D018517:Plant Roots; D018547:Plant Stems
chemical_list: D000900:Anti-Bacterial Agents; D010936:Plant Extracts
keywords: ATCC; Alchornea floribunda; American type culture collection; Antibacterial activity; CFU/ml; CHCl(3); DMSO; EtOAc; EtOH; Euphorbiaceae; HNC; Herbier National du Cameroun; INT; IZD; MIC; MeOH; chloroform extract; colony forming units/ml; dimethyl sulfoxide; ethanol extract; ethyl acetate extract; inhibition zone diameter; iodonitrotetrazolium chloride; methanol extract; minimum inhibitory concentration; w/v; weight by volume