Abstract
Astaxanthin, a carotenoid endowed with potent antioxidant capacity, exhibits considerable application prospects in nutraceuticals, pharmaceuticals, and cosmetics. In contrast to the chemical synthesis method, the biosynthesis of astaxanthin is undoubtedly a greener and more environmentally friendly production approach. In this review, we comprehensively review the biosynthetic pathways and multiple strategies for astaxanthin synthesis in Phaffia rhodozyma. Some biotechnology advancements for increasing the yield of astaxanthin in Phaffia rhodozyma encompass mutagenesis breeding, genetic modification, and optimizing fermentation conditions, thereby opening up new avenues for its application in functional foods and feed. Nevertheless, the yield of product synthesis is constrained by the host metabolic stoichiometry. Besides breaking the threshold of astaxanthin production and alleviating the impact of astaxanthin accumulation on cell growth, a comprehensive comprehension of multiple interconnected metabolic pathways and complex regulatory mechanisms is indispensable for significantly enhancing astaxanthin production. This review presents some prospects of integrating digital concepts into astaxanthin production to aid in overcoming current challenges.