Specific probiotic characterization of Weissella hellenica DS-12 isolated from flounder intestine.

Abstract

Lactic acid bacteria (LAB) as probiotics have played an important role in beneficial functions for industrial animals (Pedigon et al., 1995). The administration of LAB improves intestinal microflora and promotes animal and human health. Gilliland et al. (1980) speculated that calves fed pasteurized whole milk containing Lactobacillus acidophilus exhibited greater increases in the number of lactobacilli and greater reductions in the number of coliforms in the feces. Pollman et al. (1980) reported that the administration of L. acidophilus induces a growth promotion effect in sibling and nearly mature pigs. However, the specific probiotics for inland or sea fish have not yet been developed. Lactobacillus DS-12 for sea fish production was isolated by Byun et al. (1997), and they reported that in the administration of DS-12 to flounder, the number of lactic acid bacteria became significantly higher and the number of coliforms significantly lower in feces than in control subjects, and that the oral administration of DS-12 effectively promoted the growth of flounder. The DS-12 strain was identified as a Lactobacillus species on the basis of some phenotypical characteristics (Byun et al., 1997), but its true taxomomic position was unclear.Because of the uncertain position of DS-12, in the present study its 16S rRNA sequencing, DNA-DNA homology experiments, and probiotics characterizations were studied. Materials and MethodsStrains studied. A total of 199 bacteria strains were isolated from the intestinal contents of 100 flounders. After the screening, the isolate DS-12 was selected as a probiotic strain (Byun et al., 1997 A total of 199 microorganisms were isolated from the intestinal contents of flounder (Paralichthys olivaceus) in a fish farm in Seoul, Korea. Among these strains, DS-12 was selected as a candidate for flounder probiotics because of its excellent exhibition of antimicrobial activity against fish pathogens such as edwardsiella, pasteurella, aeromonas, and vibrio, and initiate growth in 10% NaCl, 10% bile, and in broth at pH 3 for 90 min. This strain was Gram-positive, and catalase-negative coccoid rods that produced gas from glucose and formed more than 90% of lactate as the D(؊) isomer. This organism is positioned at a cluster in the genus Weissella on the phylogenetic tree based on 16S rRNA sequences, which were assigned to Weissella hellenica on the basis of DNA-DNA relatedness. However, the type strain of W. hellenica JCM 10103 T had no antibacterial activity against the fish pathogenic bacteria and was found to be quite different from the DS-12 strain in some sugar fermentation patterns of a a-methyl-D-glucoside, esculine, cellobiose, melibiose, D-raffinose, and D-turanose, being especially unable to grow at 15 and 35°C in 7% NaCl and 10% bile. The results obtained in the present study demonstrated that the type strain of W. hellenica had no probiotic characteristics, but the strain DS-12 could be used as a specific probiotic for flounder.

Classification and characterization of lactic acid bacteria isolated from the intestines of common carp and freshwater prawns.

“…Isolates from the intestines of animals have been identified as Enterococcus faecalis, Enterococcus faecium, Enterococcus hirae, Enterococcus durans, and Weissella hellenica (Cai et al, 1998;Devriese et al, 1987). In the present study, all isolates were isolated from the intestines of common carp and freshwater prawns at a level of 10 7 Ϫ10 8 cfu/g.…”

Identification and characterization of lactic acid bacteria isolated from Tibetan Qula cheese

“…Nucleotide substitution rates were calculated, and phylogenetic trees were constructed by the neighbor-joining method. Bacillus subtilis NCDO 1769 was used as an outgroup organism (Cai et al, 1998a(Cai et al, , c, 1999c. The topologies of trees were evaluated by bootstrap analysis of the sequence data with CLUSTAL W software based on 100 random resamplings (Thompson et al, 1994).…”

First description of a novel Weissella species as an opportunistic pathogen for rainbow trout Oncorhynchus mykiss (Walbaum) in China

“…reports associated with fish and fish products were rare. Weissella hellenica was isolated from the intestinal contents of flounder (Paralichthys olivaceus) (Cai et al, 1998). Weissella thailandensis was described from fermented fish (pla-ra, pla-com) in Thailand (Tanasupawat et al, 2000).…”