Productive Potential of Rhodotorula Biomass: Carotenoid Biosynthesis, Antioxidant Activity and Nutritional Composition

The increasing demand for natural pigments, antioxidant compounds, and nutritionally valuable microbial biomass has intensified interest in yeasts of the genus Rhodotorula as potential food and biotechnological resources. This study aimed to evaluate the productive, nutritional, and antioxidant potential of Rhodotorula mucilaginosa CNMN-YS-09 and Rhodotorula mucilaginosa CNMN-YS-10 following reactivation and regeneration in the presence of 1, 5, and 10% mannoprotein extracts (MP) obtained from brewing and winemaking yeast biomass. The strains were cultivated in 6 °Blg beer wort at 28±1°C for 120 h. We evaluated biomass productivity, carotenoid productivity and content, protein and carbohydrate composition, DPPH and ABTS radical-scavenging activities, and catalase activity. The response to MP supplementation was strain-, extract-origin-, and concentration-dependent. Rhodotorula mucilaginosa CNMN-YS-09 exhibited the highest carotenogenic potential, with MPB increasing carotenoid productivity by 44.2 - 83.2% and specific carotenoid content by 61.1%, reaching 165.35±0.5 µg/g biomass, accompanied by enhanced DPPH radical-scavenging activity. Rhodotorula mucilaginosa CNMN-YS-10 showed higher protein accumulation and a more pronounced enzymatic antioxidant response, with catalase activity reaching 260.06±0.3 mmol min⁻¹ mg⁻¹ protein. Overall, the findings highlight the potential of Rhodotorula biomass as a multifunctional food-related resource containing carotenoids, proteins, carbohydrates, and antioxidant compounds.