title: Phytochemical, toxicological and antimicrobial evaluation of Lawsonia inermis extracts against clinical isolates of pathogenic bacteria.
abstract: BACKGROUND
  The emerging resistance of pathogen against the currently available antimicrobial agents demands the search of new antimicrobial agents. The use of medicinal plants as natural substitute is the paramount area of research to overwhelm the drug resistance of infectious agents. Scientists have not made enough effort on the evaluation of safety of medicinal plant yet.
  
  
  METHODS
  In the present study antimicrobial activity of Lawsonia inermis is investigated against clinical isolates of seven bacteria including four Gram negative (Escherichia coli, Salmonella typhi, Klebsiella spp., Shigella sonnei) and three Gram positive (Bacillus subtilis, Staphylococcus aureus, Staphylococcus epidermidis) using disc diffusion method. Four types of Lawsonia inermis extracts were prepared using methanol, chloroform, acetone and water as extraction solvents, while DMSO (Dimethyl sulfoxide) and water as dissolution solvents. The rate and extent of bacterial killing was estimated by time-kill kinetic assay at 1× MIC of each bacterial isolate. The overall safety of Lawsonia inermis extracts was assessed in mice.
  
  
  RESULTS
  Lawsonia inermis displayed noteworthy antimicrobial activity against both gram positive and gram negative bacterial strains used in the study. The minimum value of MIC for different bacterial strains ranged from 2.31 mg/ml to 9.27 mg/ml. At 1x MIC of each bacterial isolate, 3log10 decrease in CFU was recorded after 6 hours of drug exposure and no growth was observed in almost all tested bacteria after 24 hours of exposure. No sign of toxidrome were observed during in vivo toxicity evaluation in mice at 300 mg/kg concentration.
  
  
  CONCLUSIONS
  In conclusion, the present study provides the scientific rational for medicinal use of Lawsonia inermis. The use of Lawsonia inermis extracts is of great significance as substitute antimicrobial agent in therapeutics.
authors.affiliation: Institute of Biochemistry and Biotechnology, Quid-i-Azam Campus, University of the Punjab, Lahore 54590, Pakistan. iramgull86@yahoo.com.
authors.forename: Iram
authors.initials: I
authors.lastname: Gull
authors.forename: Maria
authors.initials: M
authors.lastname: Sohail
authors.forename: Muhammad Shahbaz
authors.initials: MS
authors.lastname: Aslam
authors.forename: Muhammad
authors.initials: M
authors.lastname: Amin Athar
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology* / Q000633:toxicity*; D001681:Biological Assay; D015169:Colony Count, Microbial; D004195:Disease Models, Animal; D006090:Gram-Negative Bacteria / Q000187:drug effects*; D006094:Gram-Positive Bacteria / Q000187:drug effects*; D031564:Lawsonia Plant / Q000737:chemistry*; D051379:Mice; D008826:Microbial Sensitivity Tests; D064209:Phytochemicals / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology* / Q000633:toxicity*; D011041:Poisoning / Q000473:pathology
chemical_list: D000900:Anti-Bacterial Agents; D064209:Phytochemicals