Antimicrobial activity of plumbagin, a naturally occurring naphthoquinone from Plumbago rosea, against Staphylococcus aureus and Candida albicans

Int J Med Microbiol. 2016 Jun;306(4):237-48. doi: 10.1016/j.ijmm.2016.05.004. Epub 2016 May 10.

Abstract

Candida albicans and Staphylococcus aureus are opportunistic pathogens. Despite causing a number of independent infections, both pathogens can co-infect to cause urinary tract infections, skin infections, biofilm associated infections, sepsis and pneumonia. Infections of these two pathogens especially their biofilm associated infections are often difficult to treat using currently available anti-bacterial and anti-fungal agents. In order to identify a common anti-microbial agent which could confer a broad range of protection against their infections, we screened several phytochemicals and identified plumbagin (5-hydroxy-2-methyl-1,4-naphthoquinone), a phytochemical from Plumbago species as a potent antimicrobial agent against S. aureus and C. albicans, with a minimum inhibitory concentration of 5μg/ml. Antimicrobial activity of plumbagin was validated using an ex-vivo porcine skin model. For better understanding of the antimicrobial activity of plumbagin, a Drosophila melanogaster infection model was used, where D. melanogaster was infected using S. aureus and C. albicans, or with both organisms. The fly's survival rate was dramatically increased when infected flies were treated using plumbagin. Further, plumbagin was effective in preventing and dispersing catheter associated biofilms formed by these pathogens. The overall results of this work provides evidence that plumbagin, possesses an excellent antimicrobial activity which should be explored further for the treatment of S. aureus and C. albicans infections.

Keywords: Bacteria; Biofilm; Fungus; Phytochemicals; Plumbagin.

MeSH terms

  • Animals
  • Anti-Infective Agents / chemistry
  • Anti-Infective Agents / isolation & purification
  • Anti-Infective Agents / pharmacology*
  • Biofilms / drug effects
  • Candida albicans / drug effects*
  • Candida albicans / physiology
  • Candidiasis / drug therapy
  • Disease Models, Animal
  • Drosophila melanogaster
  • Female
  • Microbial Sensitivity Tests
  • Naphthoquinones / chemistry
  • Naphthoquinones / isolation & purification
  • Naphthoquinones / pharmacology*
  • Phytochemicals / chemistry
  • Phytochemicals / isolation & purification
  • Phytochemicals / pharmacology*
  • Plumbaginaceae / chemistry
  • Staphylococcal Infections / drug therapy
  • Staphylococcus aureus / drug effects*
  • Staphylococcus aureus / physiology
  • Survival Analysis
  • Treatment Outcome

Substances

  • Anti-Infective Agents
  • Naphthoquinones
  • Phytochemicals
  • plumbagin