Antioxidant Potential and Antimicrobial Activity of Allium sativum, Cinnamomum zeylanicum, and Azadirachta indica Against Free Radicals and Microbes in Diseased Tilapia

The present study investigates the antioxidant activity, mineral profile, and antimicrobial efficacy of Azadirachta indica (neem), Allium sativum (garlic), and Cinnamomum zeylanicum (cinnamon) extracts. The total phenolic content was highest in A. indica, moderate in A. sativum, and lowest in C. zeylanicum. Antioxidant and free radical scavenging activities were evaluated in vitro using FRAP, DPPH, and ABTS assays, along with copper and iron chelating, superoxide, and hydroxyl scavenging activities. The findings indicate that all plant extracts possess significant antioxidant and free radical scavenging activities, attributed to their phenolic and flavonoid contents. The antimicrobial activity was assessed using two bacterial strains, Pseudomonas sp. and Aeromonas hydrophila, isolated from diseased tilapia. A. indica's ethanolic extract exhibited the highest inhibition against both strains, followed by moderate activity from A. sativum and the least from C. zeylanicum. These results suggest that garlic, cinnamon, and neem have strong antioxidant and antimicrobial properties, potentially beneficial for pharmaceutical applications targeting various human health disorders.