Abstract:Moringa oleifolia seed meal is abundant in bioactive compounds， which may be utilized as natural preservatives. This paper explored the inhibitory effects of ethanol extracts of different concentrations from Moringa oleifolia seed meal on Vibrio parahaemolyticus （VP） and Staphylococcus aureus （S. aureus）， selected the ethanol extracts with the strongest antibacterial activity， and determined their antibacterial stability and freshkeeping effect of salmon. The results showed that 60% ethanol extract had a better inhibitory effect on VP and S. aureus with minimal inhibitory concentration （MIC） of 0.08， 0.16 mg/mL， respectively. The antibacterial activity of 60% ethanol extract decreased after high-temperature treatment. Antibacterial activity was almost not affected by acid treatment. However， the antibacterial activity significantly decreased after alkali treatment， but the antibacterial efficiency was over 61%. Antibacterial activity was not significantly affected by longterm ultraviolet radiation （P＞0.05）. 60% ethanol extract could effectively inhibit the change in pH， lipid oxidation， juice loss， color， and sensory indexes of salmon. In terms of the inhibitory effect on microorganisms，compared with that of the control group， the shelf life of salmon treated with 10 mg/mL ethanol extract from Moringa oleifolia seed meal was extended by about 3 days. In summary， 60% ethanol extract from Moringa oleifolia seed meal had good antibacterial effects and stable antibacterial activity， which could effectively prolong the shelf life of salmon.