Biosynthetic capabilities of Antarctic yeast Sporobolomyces roseus AL103: Temperature influence on intracellular metabolites and characterization of the exopolysaccharide.

Abstract

The purpose of the study was to investigate the biosynthetic properties of the Antarctic yeast strain Sporobolomyces roseus AL₁₀₃ in response to temperature changes, to perform intracellular metabolic profiling, and to reveal the chemical and functional characteristics of the synthesized exopolysaccharide (EPS). The results show that the yeast strain needed a shorter time to reach a stationary phase at 22 °C contrary to that of 5 °C. An NMR analysis revealed differences in metabolic profiles of amino acids, glucose, trehalose, glycerol, uridine, etc. EPS (2.9 g/L) was characterized by high-molecular-weight with total carbohydrate, uronic acids, and protein content of 66 %, 10.5 %, and 2.5 %, respectively. Mannose (74 mol%) and galactose (19 mol%) were the major constituents. The FT-IR data suggested the presence of β-(1-4)-mannan. DSC thermogram, WVTR, mechanical properties, and moisture sorption of the EPS film showed thermal stability up to 220 °C and hydrophilic behavior. The newly obtained polymer film was studied for the first time and the data showed possibilities for its successful application as a film-forming material in the preparation of packaging materials. In conclusion, the temperature influenced the metabolic profile of the Antarctic yeast producer. The biotechnological process could be directed to obtain the target intracellular or extracellular metabolites.