title: In vitro and in vivo bactericidal activity of Vitex negundo leaf extract against diverse multidrug resistant enteric bacterial pathogens.
abstract: OBJECTIVE
  To investigate in vitro and in vivo antibacterial potentials of Vitex negundo (V. negundo) leaf extracts against diverse enteric pathogens.
  
  
  METHODS
  Water and methanol extracts of V. negundo leaves were evaluated against enteric bacterial pathogens by using standard disc diffusion, viable bacterial cell count methods, determination of minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC).
  
  
  RESULTS
  Methanol extract of V. negundo leaves showed potent antibacterial activity (inhibition zone: 9.9-22.6 mm, MIC: 200-3200 μg/mL, MBC: 200-6400 μg/mL) against all the pathogenic enteric bacteria (Vibrio cholerae, Vibrio parahaemolyticus, Vibrio mimicus, Echerichia coli, Shigella spps., and Aeromonas spps) tested. Methanol extract of V. negundo leaves showed potent bactericidal activity both in vitro laboratory conditions (MBC, 200-400 μg/mL) and in the intestinal environment (Dose, 1-2 mg/mL) of infant mice against pathogenic Vibrio cholerae, the major causative agent of cholera. Furthermore, assays using the mice cholera model showed that V. negundo methanol extract can protect mice from Vibrio cholerae infection and significantly decrease the mortality rate (P<0.0001).
  
  
  CONCLUSIONS
  For the first time we showed that methanol extract of V. negundo leaves exhibited strong vibriocidal activity both in vitro and in vivo conditions. Therefore, it will be useful to identify and isolate the active compounds of this extract that could be a good alternative of antibiotics to treat cholera.
authors.affiliation: Molecular Genetics Laboratory, International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka-1212, Bangladesh. kamruzzaman@icddrb.org
authors.forename: Muhammad
authors.initials: M
authors.lastname: Kamruzzaman
authors.forename: S M Nayeemul
authors.initials: SM
authors.lastname: Bari
authors.forename: Shah M
authors.initials: SM
authors.lastname: Faruque
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects*; D024901:Drug Resistance, Multiple, Bacterial; D005260:Female; D007422:Intestines / Q000382:microbiology; D008297:Male; D000432:Methanol / Q000737:chemistry; D051379:Mice; D008826:Microbial Sensitivity Tests; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D016019:Survival Analysis; D014735:Vibrio Infections / Q000188:drug therapy / Q000382:microbiology; D020950:Vitex / Q000737:chemistry*
chemical_list: D000900:Anti-Bacterial Agents; D010936:Plant Extracts; D000432:Methanol