In Vitro Evaluation of the Antibacterial and Antioxidant Activities of Extracts of Gracilaria gracilis with a View into Its Potential Use as an Additive in Fish Feed

Fish in aquaculture systems are subject to several stressors that inhibit the immune response and potentiate development of disease increased mortality. The inclusion additives fish diet, namely seaweeds or their extracts, natural sources bioactive compounds can be an important tool for promoting health well-being these animals. present study aims at sustainable effective methodologies extraction red seaweed Gracilaria gracilis, exploring its antibacterial antioxidant potential considering use as additive functional feeds. yield methods was evaluated upon sequential solid–liquid techniques with ethanol water solvents, different temperatures (room temperature: 40 °C 70 °C), time. results demonstrated adoption times 30 min provided higher yields. We also capacity properties obtained extracts against strains cause diseases by disk diffusion broth microdilution methods. activity determined DPPH reducing method quantification total polyphenols content (TPC). With results, we establish procedures allow future G. gracilis effects a safe way.