Comparative analysis of growth, biomass and antioxidative responses in microalgae: a study of Chlorella vulgaris, Isochrysis galbana and Tetraselmis chui across growth phases.

Microalgae are a promising source of natural antioxidants, but optimising culture conditions to enhance antioxidant production remains a significant challenge, as varying cultivation environments induce oxidative stress and promote antioxidant accumulation. This study aims to assess the production of enzymatic (superoxide dismutase, SOD; catalase, CAT; ascorbate peroxidase, APX; guaiacol peroxidase, GPX; glutathione reductase, GR) pigments and non-enzymatic antioxidants (chlorophylls, Chls; carotenoids, CAR; ascorbic acid, AsA; a-tocopherol, TOC; total glutathione, GSH) in Chlorella vulgaris (UMT-M1), Isochrysis galbana (SWC002), and Tetraselmis chui (SWC001) at different growth phases. Throughout the cultivation period, the early stationary phase was observed to be the most significant increase phase for most antioxidants. All tested species formed TOC in the largest amounts during this phase. In this phase, C. vulgaris and I. galbana had the highest CAT and GPX, whereas C. vulgaris and T. chui had the highest SOD and APX. By identifying the early stationary phase as a key growth phase for maximum antioxidant production, this research provides valuable insights into the cultivation strategies that can be employed to maximise the yield of these beneficial compounds. This study thus contributes to the growing body of knowledge necessary for commercialising microalgae-derived antioxidants, offering a sustainable and natural alternative to synthetic antioxidants. [ABSTRACT FROM AUTHOR]