Screening of microalgal strains with elevated α-tocopherol levels and antioxidant capacity for biotechnological applications.

One of the world's most important scientific challenges is addressing the global food crisis. Products offering potential health benefits, including various supplements with protective properties, have become a priority. Vitamin E is among the compounds gaining increasing attention from consumers. It is a group of compounds, with α-tocopherol of natural origin being the most bioavailable and valuable. This study investigated variations in α-tocopherol content, productivity, and antioxidant status at different growth stages in 15 microalgae strains from the Chlorophyta and Heterokontophyta. Results showed considerable diversity in α-tocopherol content, ranging from 8.0 to 773.8 µg g-1 dry weight, with a maximum for the Heterochlamydomonas strain at the late stationary phase. Significant intra‑species variability was observed, underscoring the importance of strain selection for biotechnological applications. Principal component analysis revealed distinct clustering patterns, distinguishing strains with high α-tocopherol content and antioxidant enzyme activity from those with lower levels. This underscored the intricate interplay between phylogeny, growth conditions, and antioxidant defences in microalgae. The obtained results provided opportunities for screening microalgae to obtain biomass with a high content of natural α-tocopherol, and opened new avenues for their utilisation in food supplements, cosmetics, and pharmaceuticals.