The Potential of Microalgae from Bone River Gorontalo as an Antioxidant

Abstract

Antioxidants are essential in preventing oxidative reactions caused by free radicals, which can lead to cellular  damage. Microalgae are considered a promising natural source of antioxidants due to their bioactive metabolites. This  study aimed to isolate and identify microalgae from the Bone River and assess their antioxidant activity. Microalgae  isolation was conducted using the serial dilution method, while identification was based on microscopic morphological  characteristics. The antioxidant activity was measured using the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay with a UV Vis spectrophotometer. The data were analyzed statistically using ANOVA. The results identified three main isolates:  MS 1 (Euglenophyta), MS 2 (Euglenophyta), and MS 3 (Chlorophyta). Qualitative tests confirmed positive antioxidant  activity in all n-hexane extracts. The IC50 values obtained were 86.06 μg/mL (MS 1), 82.90 μg/mL (MS 2), and 98.06  μg/mL (MS 3), indicating strong antioxidant activity. ANOVA analysis (p < 0.05) revealed significant differences when  compared to vitamin C as the control. In conclusion, microalgae isolated from the Bone River, particularly from the  Euglenophyta and Chlorophyta groups, exhibit strong antioxidant potential and may serve as a valuable natural source  for applications in the food and health industries.