Improved astaxanthin production by SK984 with oak leaf extract and inorganic phosphate supplementation.

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