Biotechnological production of astaxanthin with Phaffia rhodozyma/Xanthophyllomyces dendrorhous

The oxygenated β-carotene derivative astaxanthin exhibits outstanding colouring, antioxidative and health-promoting properties and is mainly found in the marine environment. To satisfy the growing demand for this ketocarotenoid in the feed, food and cosmetics industries, there are strong efforts to develop economically viable bioprocesses alternative to the current chemical synthesis. However, up to now, natural astaxanthin from Haematococcus pluvialis, Phaffia rhodozyma or Paracoccus carotinifaciens has not been cost competitive with chemically synthesized astaxanthin, thus only serving niche applications. This review illuminates recent advances made in elucidating astaxanthin biosynthesis in P. rhodozyma. It intensely focuses on strategies to increase astaxanthin titers in the heterobasidiomycetous yeast by genetic engineering of the astaxanthin pathway, random mutagenesis and optimization of fermentation processes. This review emphasizes the potential of P. rhodozyma for the biotechnological production of astaxanthin in comparison to other natural sources such as the microalga H. pluvialis, other fungi and transgenic plants and to chemical synthesis.