title: Antimicrobial activity of aqueous and organic extracts of a Saudi medicinal plant: Rumex nervosus.
abstract: OBJECTIVE
  The antimicrobial effect of aerial part of Rumex nervosus obtained from the Southern region of Saudi Arabia was evaluated on bacterial strains Staphylococcus aureus, methicillin resistant S. aureus, Enterococcus faecalis, Escherichia coli, Pseudomonas Aeruginosa, and fungal strain Candida albicans.
  
  
  METHODS
  The solvents used for the extraction were aqueous, hexane, and methanol. The in vitro antimicrobial activity was performed by agar diffusion and disk diffusion methods and the confirmation of this activity was done by the enumeration of colony forming units (CFU).
  
  
  RESULTS
  The aqueous extract showed the growth inhibitory effect on Gram-positive bacteria while the Gram-negative P. aeruginosa was the most sensitive microorganism as determined by the agar diffusion technique. Surprisingly, the extract showed little antibacterial activity on other Gram-negative bacteria (E. coli) by this technique. Ethanolic extract was also found to be inhibitory to the growth of microorganisms. Hexane extract was relatively low in antimicrobial activity on Gram-negative E. coli and P. aeruginosa, while both the organic extracts were inhibitory to the growth of the fungus, C. albicans. Hexane gave no conclusive results with agar or disk diffusion methods, but showed the microbial growth inhibition in CFU enumeration. The antibacterial activity of active extracts was compared with vancomycin while antifungal activity of was compared with amphotericin B.
  
  
  CONCLUSIONS
  The results obtained in the present study suggest that R. nervosus showed a marked antimicrobial activity with the test organisms.
authors.affiliation: Department of Research, Prince Sultan Military Medical City, Riyadh, Kingdom of Saudi Arabia.
authors.forename: Abdul Rahman K
authors.initials: AR
authors.lastname: Al-Asmari
authors.affiliation: Department of Research, Prince Sultan Military Medical City, Riyadh, Kingdom of Saudi Arabia.
authors.forename: Yunus M
authors.initials: YM
authors.lastname: Siddiqui
authors.affiliation: Department of Research, Prince Sultan Military Medical City, Riyadh, Kingdom of Saudi Arabia.
authors.forename: Md Tanwir
authors.initials: MT
authors.lastname: Athar
authors.affiliation: Department of ENT, Prince Sultan Military Medical City, Riyadh, Kingdom of Saudi Arabia.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Al-Buraidi
authors.affiliation: Department of Pharmacy, Prince Sultan Military Medical City, Riyadh, Kingdom of Saudi Arabia.
authors.forename: A S
authors.initials: AS
authors.lastname: Al-Eid
authors.affiliation: Department of Dermatology, Prince Sultan Military Medical City, Riyadh, Kingdom of Saudi Arabia.
authors.forename: Ghalib B
authors.initials: GB
authors.lastname: Horaib
keywords: Antimicrobial activity; Rumex nervosus; Saudi medicinal plant