title: Antibacterial and antibiotic-modifying activities of three food plants (Xanthosoma mafaffa Lam., Moringa oleifera (L.) Schott and Passiflora edulis Sims) against multidrug-resistant (MDR) Gram-negative bacteria.
abstract: BACKGROUND
  The present study was designed to investigate the antibacterial activities of the methanol extract of three edible plants, namely Xanthosoma mafaffa, Moringa oleifera and Passiflora edulis and their synergistic effects with some commonly used antibiotics against MDR Gram-negative bacteria expressing active efflux pumps.
  
  
  METHODS
  Broth microdilution method was used to determine the minimum inhibitory concentrations (MICs) and the minimum bactericidal concentrations (MBCs) of the extracts, as well as those of antibiotics in association with the extracts.
  
  
  RESULTS
  The phytochemical test indicate that all tested crude extracts contained polyphenols, triterpenes and steroids whilst other phytochemical classes were selectively distributed. Extracts showed antibacterial activities with minimum inhibitory concentrations ranging from 128-1024 μg/mL on the majority of the 19 tested Gram-negative bacterial strains. Extract from the pericarp of P. edulis inhibited the growth of 89.5% of the 19 tested bacterial strains, the lowest minimal inhibitory concentration (MIC) value of 128 μg/mL being recorded against Escherichia coli AG100 strain. In the presence of Phenylalanine-Arginine β-Naphtylamide (PAβN)], an efflux pump inhibitor (EPI), the activity of the extract from X. mafaffa increased on 40% of tested strains. In combination with antibiotics, extracts of X. mafaffa, M. oleifera and pericarp of P. edulis showed synergistic effects with some antibiotics against more than 75% of the tested bacteria.
  
  
  CONCLUSIONS
  The results of the present study indicate that the tested plants may be used in the treatment of bacterial infections including the multi-resistant bacteria.
authors.affiliation: Department of Biochemistry, Faculty of Science, University of Dschang, P.O. Box 67, Dschang, Cameroon.
authors.forename: Joachim K
authors.initials: JK
authors.lastname: Dzotam
authors.affiliation: Department of Biochemistry, Faculty of Science, University of Dschang, P.O. Box 67, Dschang, Cameroon.
authors.forename: Francesco K
authors.initials: FK
authors.lastname: Touani
authors.affiliation: Department of Biochemistry, Faculty of Science, University of Dschang, P.O. Box 67, Dschang, Cameroon. kuetevictor@yahoo.fr.
authors.forename: Victor
authors.initials: V
authors.lastname: Kuete
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D003124:Colorimetry; D024901:Drug Resistance, Multiple, Bacterial; D004357:Drug Synergism; D006090:Gram-Negative Bacteria / Q000187:drug effects*; D008826:Microbial Sensitivity Tests; D029588:Moringa oleifera / Q000737:chemistry; D029598:Passiflora / Q000737:chemistry; D010936:Plant Extracts / Q000494:pharmacology*; D010945:Plants, Edible / Q000737:chemistry; D031063:Xanthosoma / Q000737:chemistry
chemical_list: D000900:Anti-Bacterial Agents; D010936:Plant Extracts