Isolation and selection of new astaxanthin producing strains of Xanthophyllomyces dendrorhous

Astaxanthin is a xanthophyll pigment of high economic value for its use as a feeding component in aquaculture. Xanthophyllomyces dendrorhous is a basidiomycetous fungi able to synthesize astaxanthin as its major carotenoid, and the only known yeast species bearing the capability to produce this type of carotenoid. Recently, the habitat and intraspecific variability of this species have been found to be wider than previously expected, encouraging the search for new wild strains with potential biotechnological applications. Here we describe effective procedures for isolation of X. dendrorhous from environmental samples, accurate identification of the strains, analysis of their astaxanthin content, and proper conservation of the isolates.