Inhibitory effect of a lipopeptide biosurfactant produced by Bacillus subtilis on planktonic and sessile cells of Trichosporon spp

Biofouling. 2018 Mar;34(3):309-319. doi: 10.1080/08927014.2018.1437617. Epub 2018 Mar 21.

Abstract

The present study aimed to investigate the inhibitory effect of a bacterial biosurfactant (TIM96) on clinical strains of Trichosporon. Additionally, the effect of TIM96 on the ergosterol content, cell membrane integrity, and the hydrophobicity of planktonic cells was assessed. The inhibitory activity of TIM96 against Trichosporon biofilms was evaluated by analyzing metabolic activity, biomass and morphology. MIC values ranged from 78.125 to 312.5 μg ml-1 for TIM96; time-kill curves revealed that the decline in the number of fungal cells started after incubation for 6 h with TIM96 at both MIC and 2×MIC. The biosurfactant reduced the cellular ergosterol content and altered the membrane permeability and the surface hydrophobicity of planktonic cells. Incubation at 10×MIC TIM96 reduced cell adhesion by up to 96.89%, thus interfering with biofilm formation. This concentration also caused up to a 99.2% reduction in the metabolic activity of mature biofilms. The results indicate potential perspectives for the development of new antifungal strategies.

Keywords: Biosurfactant; Trichosporon; biofilm; fungal inhibition.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antifungal Agents / metabolism
  • Antifungal Agents / pharmacology*
  • Bacillus subtilis / metabolism*
  • Biofilms / growth & development
  • Cell Adhesion / drug effects*
  • Lipopeptides / biosynthesis
  • Lipopeptides / pharmacology*
  • Plankton / drug effects
  • Plankton / metabolism
  • Plankton / physiology
  • Surface-Active Agents / pharmacology
  • Trichosporon / drug effects*
  • Trichosporon / metabolism
  • Trichosporon / physiology

Substances

  • Antifungal Agents
  • Lipopeptides
  • Surface-Active Agents