Isolation of Weissella cibaria from Pacific White Shrimp (Litopenaeus vannamei) Gastrointestinal Tract and Evaluation of Its Pathogenic Bacterial Inhibition

Abstract

Objective: The present study reported the isolation of lactic acid bacteria from the shrimp gastrointestinal tract and evaluation of its antagonistic activity against pathogenic bacteria. Methods/ statistical analysis: Lactic bacteria from the gastrointestinal tract of alive healthy shrimp were screened on sterilized MRS medium. Vibrio sp. inhibition by isolates was conducted by the agar-well diffusion assay. The isolates were identified by 16S rRNA sequencing. Antibacterial activity was investigated against 25 Vibrio sp. isolates, Staphylococcus aureus ATCC 25023, and Escherichia coli ATCC 85922. Hemolytic activity, salt, and antibiotic resistance were also evaluated. Findings: Total of 22 isolates exhibited Vibrio parahaemolyticus inhibition with antagonistic activities ranged from 220 AU/ml to 460 AU/ml. Sequence analysis of 16S rRNA indicated the 5 isolates belong to Weissella cibaria species, namely HN02, HN03, HN04, and HN06 AND HN07. Among these, W. cibaria HN05 had highest antagonistic activity and exhibited the broad inhibition spectrum against Vibrio sp. as well as E. coli ATCC 85922 but not S. aureus ATCC 25023. β-hemolytic and salt resistance assays showed that W. cibaria HN05 had no β-hemolytic activity and grew well in medium containing 5% of salt. Antibiotic resistance analysis indicated W. cibaria HN05 was suppressed by ampicillin, chloramphenicol, oxytetracycline hydrochloride, and chlortetracycline hydrochloride. Application/improvements: This is the first study on isolation and Article Type: Article

Synbiotic Agents and Their Active Components for Sustainable Aquaculture: Concepts, Action Mechanisms, and Applications

“…The major probiotic genera used in aquaculture are Lactobacillus and Bacillus [146]. In most cases, Bacillus, Lactobacillus, Lactococcus, Leuconostoc, Pediococcus, and Weissella are isolated from fish and shellfish guts [147][148][149][150][151]. Supplementation in aquaculture feed is achieved using single-strain probiotics or associations of various bacteria as multi-strain probiotics (MSPs), which have been reported to have more beneficial effects on hosts owing to synergistic effects between various strains [152].…”