Astaxanthin is widely used in food, feed and nutraceutical industries. Xanthophyllomyces dendrorhous is one of the most promising natural sources of astaxanthin. However, the astaxanthin yield in the wild-type X. dendrorhous is considered low for industrial application. In the present study, X. dendrorhous ATCC 66272 was subjected to two-staged mutagenesis: (i) UV light and (ii) N-methyl-N'-nitro-N-nitroso-guanidine (NTG) toward attaining higher astaxanthin yield. The UV-irradiation mutant, X. dendrorhous SK974 showed 1.7-fold (1.07 mg/g) higher astaxanthin production as compared with the wild-type strain (0.65 mg/g). The UV mutant strain was then treated with NTG, designated as X. dendrorhous SK984, displayed further 1.4-fold (1.45 mg/g) higher astaxanthin production. Furthermore, the oak leaf extract (5%, v/v) and inorganic phosphate (KH2PO4, 3 mM) supplementation resulted about 1.4-fold (1.98 mg/g) higher astaxanthin production as compared with control (1.45 mg/g) in X. dendrorhous SK984. These findings serve as a platform suggesting that intersecting approaches might be aimed toward systematically enhanced astaxanthin production.
Keywords: Astaxanthin; Inorganic phosphate; Mutagenesis; Oak leaf extract; X. dendrorhous.