2025, Vol. 6, Issue 2, Part E

Kojic acid is a fungal secondary metabolite extensively used in pharmaceutical and cosmetic formulations due to its antioxidant, antimicrobial, and metal chelating properties. The present study aimed to investigate the influence of different solvents on the extraction efficiency and in-vitro biological activities of kojic acid. Kojic acid was extracted using water, methanol, ethanol, acetone, and chloroform, and the percentage yield was determined. Qualitative phytochemical screening confirmed the presence of phenolic compounds, characteristic of kojic acid, while other phytoconstituents were absent. The antimicrobial activity was evaluated against Staphylococcus aureus and Pseudomonas aeruginosa using the agar well diffusion method. Antioxidant activity was assessed by the DPPH free radical scavenging assay, and iron chelating potential was determined using the ferrozine assay. Among the tested solvents, methanol and ethanol produced the highest extraction yields and demonstrated superior antimicrobial, antioxidant, and chelating activities. Kojic acid exhibited stronger antimicrobial activity against Gram-positive bacteria than Gram-negative bacteria, along with concentration-dependent antioxidant and metal chelating effects. The findings indicate that solvent polarity significantly influences the biological efficacy of kojic acid and support its potential application as a natural antioxidant and antimicrobial agent in pharmaceutical and cosmetic formulations.