Genomic Insight and Optimization of Astaxanthin Production from a New Rhodotorula sp. CP72-2

Astaxanthin is a carotenoid pigment extensively used in various industries. Rhodotorula
sp. CP72-2, isolated from Calotropis gigantea, showed potential astaxanthin production. In this study,
strain CP72-2 was identified as a putative new species in the genus Rhodotorula based on the 26S rRNA
gene sequence (98% identity). It was first used as the microbial source for producing astaxanthin.
Strain CP72-2 was screened for its astaxanthin production and was identified and quantified by
High-Performance Liquid Chromatography (HPLC), Liquid Chromatography-Mass Spectrometry
(LC-MS), and UV-Vis spectrophotometer. After a screening of astaxanthin production, various carbon
sources, pH, temperature, and incubation period were evaluated for their effect on the astaxanthin
production of strain CP72-2. Among the several experimental factors, the most efficient conditions
for astaxanthin production were glucose (50 g/L), pH 4.5, 25 C, and three days of cultivation. The
assembly genome of strain CP72-2 has a total length of 21,358,924 bp and a GC content of 64.90%. The
putative candidate astaxanthin biosynthesis-associated genes (i.e., CrtE, CrtYB, CrtI, CrtS, CrtR, CrtW,
CrtO, and CrtZ) were found. This research presents the first report on the production and optimization
of astaxanthin from strain CP72-2 and its genome analysis, focusing on the biotechnological potential
of the astaxanthin producer.