title: In vitro antibacterial and antibiotic-potentiation activities of four edible plants against multidrug-resistant gram-negative species.
abstract: BACKGROUND
  The present study was designed to investigate the antibacterial activities of the methanol extracts of four Cameroonian edible plants, locally used to treat microbial infections, and their synergistic effects with antibiotics against a panel of twenty nine Gram-negative bacteria including Multi-drug resistant (MDR) phenotypes expressing active efflux pumps.
  
  
  METHODS
  The broth microdilution method was used to determine the minimum inhibitory concentrations (MICs) of the extracts [alone and in the presence of the efflux pumps inhibitor (EPI) Phenylalanine-Arginine β-Naphtylamide (PAβN)], and those of antibiotics in association with the two of the most active ones, Piper nigrum and Telfairia occidentalis. The preliminary phytochemical screening of the extracts was conducted according to the standard phytochemical methods.
  
  
  RESULTS
  Phytochemical analysis showed the presence of alkaloids and flavonoids in all studied extracts. Other chemical classes of secondary metabolites were selectively present in the extracts. The results of the MIC determination indicated that the crude extracts from P. nigrum and V. amygdalina were able to inhibit the growth of all the twenty nine studied bacteria within a concentration range of 32 to 1024 μg/mL. At a similar concentration range (32 to 1024 μg/mL) the extract from T. occidentalis inhibited the growth of 93.1% of the tested microorganisms. At MIC/2 and MIC/5, synergistic effects were noted between the extracts from P. nigrum and T. occidentalis and seven of the tested antibiotics on more than 70% of the tested bacteria.
  
  
  CONCLUSIONS
  The overall results of the present study provide information for the possible use of the studied edible plants extracts in the control of bacterial infections including MDR phenotypes.
authors.affiliation: Department of Biochemistry, Faculty of Science, University of Dschang, Dschang, Cameroon.
authors.forename: Jaurès A K
authors.initials: JA
authors.lastname: Noumedem
authors.forename: Marius
authors.initials: M
authors.lastname: Mihasan
authors.forename: Jules R
authors.initials: JR
authors.lastname: Kuiate
authors.forename: Marius
authors.initials: M
authors.lastname: Stefan
authors.forename: Dumitru
authors.initials: D
authors.lastname: Cojocaru
authors.forename: Jean P
authors.initials: JP
authors.lastname: Dzoyem
authors.forename: Victor
authors.initials: V
authors.lastname: Kuete
mesh_terms: D000470:Alkaloids / Q000737:chemistry / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002163:Cameroon; D019662:Cucurbitaceae / Q000737:chemistry*; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects; D005419:Flavonoids / Q000737:chemistry / Q000494:pharmacology; D006090:Gram-Negative Bacteria / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D008826:Microbial Sensitivity Tests; D029222:Piper nigrum / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D010945:Plants, Edible / Q000737:chemistry; D027842:Syzygium / Q000737:chemistry*; D035741:Vernonia / Q000737:chemistry*
chemical_list: D000470:Alkaloids; D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D005419:Flavonoids; D010936:Plant Extracts