The increasing demand for sustainable agricultural practices has led to the exploration of biocontrol microorganisms like Metschnikowia pulcherrima, known for its ability to combat fruit pathogens. Despite its potential, the optimization of its growth conditions remains underexplored. This study utilized various experimental design approaches to optimize the media composition and growth parameters for M. pulcherrima strain APC 1.2. Initially, a screening was conducted to identify the best carbon source for the yeast's growth. Then, using shake flask tests, the Full Mixed Factorial Approach was used to find the optimal ratio of sucrose to yeast extract. Central Composite Design (CCD) was utilized to optimize the pH and temperature conditions in 1L bioreactors under aerobic conditions. The Crabtree effect of the strain was assessed, showing that the M. pulcherrima APC 1.2 is Crabtree-negative. Finally, the Taguchi experimental design was employed in deep well plates to assess the impact of incorporating essential micro and macro nutrients into the complex medium. By systematically varying key factors such as nutrient concentrations, pH, and temperature, we identified the optimal conditions that maximize the yeast's growth. The study provides a comprehensive framework for future research, enabling further refinement of growth conditions to fully harness the potential of M. pulcherrima in various agricultural settings.
