The antibacterial activity against MRSA strains and other bacteria of a <500Da fraction from maggot excretions/secretions of Lucilia sericata (Diptera: Calliphoridae)

Microbes Infect. 2008 Apr;10(4):325-33. doi: 10.1016/j.micinf.2007.12.011. Epub 2007 Dec 28.


The application of Lucilia sericata larvae to chronic, infected wounds results in the rapid elimination of infecting microorganisms, including MRSA. Previously, we demonstrated in vitro antibacterial activity of native excretions/secretions (nES) from L. sericata and partially purified two low mass antibacterial compounds with masses of 0.5-10kDa and <500Da. The present study reports the antibacterial effects of the <500Da fraction (ES<500) on the growth and morphology of a range of bacteria, including 12 MRSA strains. Distinct morphological changes were observed in Bacillus cereus and Escherichia coli following exposure to ES<500. Flow cytometry and confocal microscopy analyses, in conjunction with turbidometric and CFU assays, revealed bacteriostatic activity of nES against S. aureus and E. coli. ES<500 also demonstrated bacteriostatic activity against S. aureus, however, bactericidal activity and the induction of a viable but non-culturable state were observed with ES<500-treated E. coli.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anti-Bacterial Agents / chemistry*
  • Anti-Bacterial Agents / isolation & purification
  • Anti-Bacterial Agents / pharmacology*
  • Cell Extracts / chemistry*
  • Colony Count, Microbial
  • Diptera / chemistry*
  • Gram-Negative Bacteria / cytology
  • Gram-Negative Bacteria / drug effects*
  • Gram-Negative Bacteria / growth & development
  • Gram-Positive Bacteria / cytology
  • Gram-Positive Bacteria / drug effects*
  • Gram-Positive Bacteria / growth & development
  • Larva / chemistry
  • Microbial Viability
  • Molecular Weight


  • Anti-Bacterial Agents
  • Cell Extracts