Assessment of Lactic Acid Bacteria Isolated from the Whiteleg Shrimp (Penaeus vannamei) as Potential Biocontrol against Pathogenic Vibrio

In aquaculture, the use of probiotics holds promise for disease prevention and nutritional enhancement. This study aimed to assess the inhibitory ability of lactic acid bacteria isolated from the hepatopancreas and intestine of healthy whiteleg shrimp (Penaeus vannamei) against prevalent shrimp pathogens. Four lactic acid bacteria were isolated from the hepatopancreas, while six isolates were obtained from the intestine. Molecular analysis, based on partial 16S rDNA gene sequencing and subsequent phylogenetic analyses, confirmed that nine isolates belonged to Pediococcus pentosaceus, while one isolate showed close relation to Weissella paramesenteroides. The cell-free supernatants from these isolates exhibited inhibitory effect against at least two of the three pathogenic Vibrio strains—Vibrio alginolyticus, Vibrio harveyi, and Vibrio parahaemolyticus. Among them, supernatants from three isolates displayed strong inhibitory responses against V. parahaemolyticus, while eight were strong against V. harveyi. Conversely, supernatants from seven isolates demonstrated medium inhibitory activity against V. alginolyticus. This investigation highlights the potential of these lactic acid bacteria isolates as promising biocontrol agents against pathogenic Vibrio in shrimp. © 2025, Egyptian Society for the Development of Fisheries and Human Health. All rights reserved.