PURPOSE: To easily obtain Phaffia rhodozyma yeast useful for replenishing feed coloring matter by culturing Phaffia rhodozyma yeast under specific conditions followed by chemically conducting a cell wall treatment.
CONSTITUTION: Phaffla rhodozyma yeast (e.g. IFO 10129 strain) is cultured ≥150h after its proliferation period in the presence of nutrient, raising the stability of astaxanthin in the microbes. When the microbes are chemically subjected to cell wall treatment after the culture, the objective Phaffia rhodozyma yeast high in astaxanthin stability and color tone-improving effect and easy to extract astaxanthin is obtained. When a proliferation-limiting period under conditions with limited nutrient is provided prior to the chemical treatment, the objective Phaffia rhodozyma with higher astaxanthin stability and greater color tone-improving effect can be obtained.
UEDA YASUYOSHI
IMAMURA SHIRO
