Fraunhofer Research Institution for Individualized Medical Technology and Engineering IMTE
Fraunhofer Research Institution for Individualized Medical Technology and Engineering IMTE

Purple4Life

Purple4Life: PPB as a Sustainable Feed Ingredient for Rainbow Trout

Within the Purple4Life project, Fraunhofer IMTE and Nofima are investigating the potential of purple phototrophic bacteria (PPB) as an innovative, sustainable component of aquaculture feeds. The goal is to establish PPB as a natural alternative to synthetic antioxidants in rainbow trout farming.

Research Focus

The work centres on rainbow trout, examining how different inclusion levels of PPB in the diet influence key biological and quality parameters, including:

  • Growth performance and feed efficiency
  • Digestion and gut health
  • Overall fish health and stress resilience
  • Antioxidant capacity and mitochondrial activity
  • Fillet quality, including colour, texture, and levels of carotenoids and CoQ10

Why PPB Matter

Rainbow trout are sensitive to stressors such as handling, high stocking densities, and temperature fluctuations. These conditions increase oxidative stress, making dietary antioxidants essential for maintaining fish health and product quality.

PPB naturally contain carotenoids and coenzyme Q10, which can:

  • reduce oxidative damage
  • support stable fillet pigmentation
  • enhance fish robustness and overall health

This positions PPB as a promising solution for improving both fish welfare and product quality in a sustainable way.