Biofortification of Chlorella vulgaris With Selenium and Iron Microminerals and Investigation of Some Bioactive Compounds: A Promising Dietary Supplement.

Microalgae are excellent bioaccumulators of selenium (Se) and iron (Fe), making them ideal for use in the fortification of food and feed supplements. This study aimed to investigate the effects of varying concentrations of Se and Fe on the growth of Chlorella vulgaris and its capacity to accumulate these microminerals. The optimal concentration of each micronutrient was determined by evaluating growth parameters and metal accumulation, and the effects of these metals on various bioactive compounds were then analyzed. The highest specific growth rate and final biomass productivity were found in 50 mg L-1 Fe. The maximum accumulation of Se and Fe in C. vulgaris cells reached 81.54 ± 0.46 mg kg-1 DW at 45 mg L-1 Se and 26798.51 ± 1.49 mg kg-1 DW at 150 mg L-1 Fe, respectively. Chlorophyll a content increased in C. vulgaris treated with 15 mg L-1 Se and 50 mg L-1 Fe. In contrast, the contents of β-carotene and lycopene were not significantly affected by Se and Fe treatments. Total flavonoid content and antioxidant activity significantly increased in 15 mg L-1 Se and 50 mg L-1 Fe. The fatty acid profile indicated that unsaturated fatty acids, particularly linoleic, alpha-linolenic, and palmitoleic acid, were the dominant components identified under Se and Fe treatments. This study suggested that C. vulgaris enriched with optimal levels of Se and Fe can be regarded as a promising candidate for the development of functional foods and nutritional purposes, due to its rich bioactive compounds.