The invention relates to methods of (i) obtaining astaxanthin-overexpressing strains of X. dendrorhous and (ii) using said strains under improved fermentation conditions. The methods of selecting the strains used are based on: (i) resistance to steroid synthesis inhibitors, respiration inhibitors and compounds that induce the formation of free radicals; (ii) colour intensity of the colony and production of carotenoids in a solid medium; (iii) production of astaxanthin in darkness; (iv) production of astaxanthin at high temperatures; and (v) production of astaxanthin with carbon sources other than glucose. The inventive methods can be used effectively to select mutants of X. dendrorhous with greater production of astaxanthin than the parent strain and low accumulation of other carotenoids. The liquid medium culture of X. dendrorhous can be used to obtain a biomass that can be used directly in human and animal food.
展开▼
