Titanium dioxide-mediated fatty acids promoted carotenoid synthesis in Phaffia rhodozyma PR106 analyzed whole genome

Abstract

Carotenoid, as good colorant and antioxidant, is widely used in the fields of food, medicine and feed. The whole genome of P. rhodozyma PR106 strain with 228.77 mg/L carotenoid (mainly included astaxanthin, β-carotene and lycopene) yield was sequenced, and the genome size was 16.18 Mb, the GC content was 47%. The genetic evolution analysis indicated that PR106 greatly changed in evolution process, and closely related to P. rhodozyma CBS7918. Under 500 mg/L titanium dioxide (TiO₂) stress, carotenoid yield of PR106 was 2.15 times that of the control for 48 h, and was 305.12 mg/L in PR106 to 72 h, interestingly, the yield of oleate, linoleate and α-linolenate also increased significantly among 51 fatty acids by targeted metabolomics analysis. TiO₂ promoted carotenoid synthesis of PR106 by forming astaxanthin esters to reduce the feedback inhibition of carotenoid synthesis. These results provided a theoretical basis for carotenoid production and development using P. rhodozyma.

Keywords: Carotenoid; Fatty acid; Phaffia rhodozyma; Titanium dioxide; Whole genome.