Biochemical and antioxidant characteristics of the soil strain Chlorococcum oleofaciens (Chlorophyceae, Chlorophyta) grown in light, dark and bicarbonate conditions

This study aimed to examine the biochemical and antioxidant characteristics of a soil strain of Chlorococcum oleofaciens CAMU MZ–Ch4 (Chlorophyceae, Chlorophyta) when cultured in light, darkness, and a combination of light-bicarbonate and dark-bicarbonate in an acute 96-hour experiment. The study established that cultivation in the dark is accompanied by an increase in the antioxidant status of Chlorococcum oleofaciens CAMU MZ–Ch4 strain cells, which is associated with the accumulation of low-molecular antioxidants and the activation of antioxidant enzymes. Culturing in the dark also causes the accumulation of chlorophyll a, ascorbic acid, astaxanthin, and lipids. But biomass productivity and concentration decreased. Introducing NaHCO3 into the medium inhibits the biosynthesis and accumulation of α-tocopherol, ascorbic acid, phenolic compounds, and chlorophylls both under illuminated and in the dark. The intensity of lipid peroxidation decreases and the activity of antioxidant enzymes increases under light and in the dark conditions with NaHCO3 in the medium.