Chlorella vulgaris as a Microalgal Source of Antioxidants: A Biochemical Assessment

The objective of this study is to assess the total antioxidant capacity of the biomass derived from the freshwater microalga Chlorella vulgaris (C. vulgaris), cultivated under static aquarium conditions. C. vulgaris is known for its high protein content, essential fatty acids, vitamins, and bioactive compounds such as carotenoids, chlorophyll, phenolics, and flavonoids, which grant it significant antioxidant properties and make it valuable for nutritional and pharmaceutical applications. The biomass was dried and powdered, and its antioxidant profile was analyzed using various assays. These included Total Phenolic Content (TPC), Total Flavonoid Content (TFC), Total Antioxidant Capacity (TAC), DPPH and ABTS radical scavenging activity, and FRAP (ferric reducing antioxidant power). Results showed that the sample contained 20.90 mg GAE/g phenolics, 29.32 mg QE/g flavonoids, and exhibited a high TAC value of 44.07 mg AAE/g. Additionally, it demonstrated significant antioxidant activity in DPPH (18.21 mg AAE/g) and FRAP (16.75 mg FeSO₄E/g) tests. However, the ABTS scavenging value was relatively low (3.05 mg TE/g), possibly due to the specific radical affinity of dominant antioxidant compounds or experimental limitations. In conclusion, the rich phenolic and flavonoid content of C. vulgaris biomass has shown remarkable antioxidant activity. The results support its potential use as a natural antioxidant source in dietary supplements, functional foods, cosmetics, and pharmaceutical formulations. This research highlights the promising role of algal-derived compounds in promoting health and combating oxidative stress-related aging processes.