Antibacterial Effects of Boric Acid Against Aquatic Pathogens

Abstract

Boron is a bioactive trace element generally found in rock, soil, water and air. It is an essential micronutrient for plants besides having beneficial effects on biological functions of human and animal health. Boric acid has antibacterial properties. Thus, the aim of this study was to evaluate the possible bactericidal and bacteriostatic effects of boric acid on the aquatic pathogens: Aeromonas veronii, Photobacterium damselae subsp. damselae, Vibrio anguillarum, Vibrio vulnificus, Vibrio harveyi, Vibrio rotiferianus, Vibrio tubiashii, Vibrio parahaemolyticus, Vibrio furnissii, and Vibrio fluvialis. The inhibitory properties of boric acid were detected by agar well diffusion, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) methods. The results showed that Photobacterium damselae subsp. damselae and Vibrio species were resistant to different concentrations of boric acid. However, boric acid showed an inhibitory effect against Aeromonas veronii at concentrations of 3.09 and 1.54 mg/ml and zone diameters on the agar were measured as 19.4 ± 0.5, 15.92 ± 0.6 mm, respectively. The MIC and MBC of boric acid for Aeromonas veronii were found to be effective at a concentration of 1.54 mg/ml. These results suggested that boric acid might serve as a potential antimicrobial agent for Aeromonas veronii in aquaculture.