Antibacterial activity of coffee extracts and selected coffee chemical compounds against enterobacteria

J Agric Food Chem. 2006 Nov 15;54(23):8738-43. doi: 10.1021/jf0617317.


The in vitro antimicrobial activity of commercial coffee extracts and chemical compounds was investigated on nine strains of enterobacteria. The antimicrobial activity investigated by the disc diffusion method was observed in both the extracts and tested chemical compounds. Even though pH, color, and the contents of trigonelline, caffeine, and chlorogenic acids differed significantly among the coffee extracts, no significant differences were observed in their antimicrobial activity. Caffeic acid and trigonelline showed similar inhibitory effect against the growth of the microorganisms. Caffeine, chlorogenic acid, and protocatechuic acid showed particularly strong effect against Serratia marcescens and Enterobacter cloacae. The IC(50) and IC(90) for the compounds determined by the microtiter plate method indicated that trigonelline, caffeine, and protocatechuic acids are potential natural antimicrobial agents against Salmonella enterica. The concentrations of caffeine found in coffee extracts are enough to warrant 50% of the antimicrobial effect against S. enterica, which is relevant to human safety.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkaloids / pharmacology
  • Anti-Bacterial Agents / pharmacology*
  • Caffeic Acids / pharmacology
  • Chlorogenic Acid / pharmacology
  • Coffea / chemistry*
  • Enterobacteriaceae / drug effects*
  • Inhibitory Concentration 50
  • Microbial Sensitivity Tests
  • Plant Extracts / pharmacology*


  • Alkaloids
  • Anti-Bacterial Agents
  • Caffeic Acids
  • Plant Extracts
  • Chlorogenic Acid
  • trigonelline
  • caffeic acid