How to Study Antimicrobial Activities of Plant Extracts: A Critical Point of View

  • Séverine Mahieux
  • Maria Susana Nieto-Bobadilla
  • Isabelle Houcke
  • Christel Neut
Part of the Sustainable Development and Biodiversity book series (SDEB, volume 19)


Multiresistance to antibiotics is a global threat for our quality of life. New weapons are urgently needed, and natural compounds regain interest. Research on antimicrobial compounds should fulfill several claims—they should be only evaluated at concentrations that could be achieved on the target—the bacterial species tested should be in agreement with the chosen application—studies should not be limited to a single strain. Conventional antimicrobial research is conducted in vitro for substances affecting growth by determining the minimal inhibitory concentrations (MICs). Research can further be refined by determining the kill time, the growth rate at sub-MICs concentration, the post-antibiotic effect, and synergy with other compounds like antibiotics. But features not related to bacterial growth can also reduce the infectious risk like anti-biofilm, anti-adherence, and antitoxin strategies. They can be determined both in vitro and in vivo but only in vivo infection models show directly the effect on the expression of the pathogenicity. The search of the mode of action can give useful insights in toxicity and drug interactions. Scientific tools in genomics and chemistry are steadily increasing to improve this topic. Bio-guided isolation of active compounds enhances detection of active compounds in the yet underexploited nature.


Antibacterial natural compounds Minimal inhibitory concentration Growth curves Kill time Synergy with antibiotics 





American Type Culture Collection


Colony-forming unit


Deutsche Sammlung von Mikroorganismen


Fractional inhibitory index


Minimal bactericidal concentration


Minimal inhibitory concentration


Mode of action


National collection of type cultures


Post-antibiotic effect


Thin-layer chromatography


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Copyright information

© Springer International Publishing AG 2018

Authors and Affiliations

  • Séverine Mahieux
    • 1
  • Maria Susana Nieto-Bobadilla
    • 1
  • Isabelle Houcke
    • 1
  • Christel Neut
    • 1
  1. 1.Laboratoire de Bactériologie, Faculté de PharmacieINSERM U995 LIRIC, University of LilleLilleFrance

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