• Korean Journal of Poultry Science
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• v.31 no.2
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• pp.85-91
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• 2004

This study was conducted to investigate the effects of dietary direct-fed microbials(DFM) on the growth performance and nutrient digestibility in broiler chickens. A total of two hundred eighty eight broiler chickens were randomly allocated into six treaments with four replications and fed for five weeks. Dietary treatments included 1) CON (basal diet), 2) DFM-1(basal diet + 0.2% Enterococcus sp. ＆ Lactobacillus reuteri), 3) DFM-2(basal diet + 0.2% Enterococcus sp. ＆ Lactobacillus plantarum), 4) DFM-3(basal diet + 0.2% Enterococcus sp. ＆ Lactobacillus reuteri ＆ Lactobacillus plantarum), 5) DFM-4(basal diet + 0.2% Enterococcus sp. ＆ Lactobacillus reuteri ＆ Lactobacillus plantarum ＆ Yeast), 6) DFM-5(basal diet + 0.2% Enterococcus sp. ＆ Lactobacillus reuteri ＆ Lactobacillus plantarum ＆ Bacillus subtilis). During the period of 1∼3weeks, average daily gain (ADG) and Feed/Gain were not significant different among treatments. In the later(3∼5weeks) and overall period(l∼ 5weeks), ADG and Feed/Gain tended to be improved in DFM treatments compared to the control. However, there were no significant differences among DFM complexes and between control and DFM treatments. The broilers fed DFM-3 diet was showd poor growth performance compared to the broilers fed DFM-l diet and similar to the broilers fed DFM-2 diet but there was no significant differences. The treatments of DFM-4 diet added Yeast and DFM-5 added Bacillus subtilis were improved in ADG and Feed/gain but no significant differences were found and also there was no specific DFM treatments in experiment period. In digestibility, the broiler chicks fed DFM treatments tended to improve N digestibility compared to control treatment. However, they were not significantly different among the treatments. In conclusion, DFM tended to improve growth performance in later stage of broiler.

• Korean Journal of Veterinary Research
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• v.48 no.4
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• pp.441-449
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• 2008

The genus Lactobacillus is the largest of the genera included in lactic acid bacteria and is associated with mucosal membranes of human and animal. Only a few Lactobacillus plasmid-encoded functions have been discovered and used. In this study, a novel plasmid (pILR091) was isolated from a wild L. reuteri isolated from pig and described the characteristics of its replicons, genetic organization, and relationship with other plasmids. After digestion of the plasmid, pILR091, with SalI, plasmid DNA was cloned into the pQE-30Xa vector and sequenced. The complete sequence was confirmed by the sequencing of PCR products and analyzed with the Genbank database. The isolate copy number and stability were determined by quantitative-PCR. The complete sequence of L. reuteri contained 7,185 nucleotides with 39% G-C content and one cut site by two enzymes, SalI and HindIII. The similar ori sequence of the pC194- rolling circle replication family (TTTATATTGAT) was located 63 bp upstream of the protein replication sequence, ORF 1. Total of five ORFs was identified and the coding sequence represented 4,966 nucleotides (70.4%). ORF1 of pILR091 had a low similarity with the sequence of pTE44. Other ORFs also showed low homology and E-values. The average G-C content of pILR091 was 39%, similar with that of genomic DNA. The copy number of pILR091 was determined at approximately 24 to 25 molecules per genomic DNA. These results suggested that pILR091 might be a good candidate to construct a new vector, which could be used for cloning and expression of foreign genes in lactobacilli.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.23 no.1
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• pp.35-48
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• 2020

Purpose: Gastrointestinal symptoms are often related to antibiotic treatment. Their incidence, risk and protective conditions in children are not well defined and represent the aims of this study. Methods: We prospectively enrolled inpatient children submitted to antibiotic treatment. Indication, type, dose and duration of treatment, probiotic supplementation and gastrointestinal symptoms were recorded at recruitment, after two and four weeks. Antibiotic-associated diarrhea (AAD) was defined as the presence of at least 3 loose/liquid stools within 14 days from antibiotic onset. Results: AAD occurred in 59/289 (20.4%) of patients, with increased risk in children younger than 3 years (relative risk [RR]=4.25), in lower respiratory (RR=2.11) and urinary infections (RR=3.67), intravenous administration (RR=1.81) and previous AAD episodes (RR=1.87). Abdominal pain occurred in 27/289 (9.3%), particularly in children >6 years (RR=4.15), with previous abdominal pain (RR=7.2) or constipation (RR=4.06). Constipation was recorded in 23/289 (8.0%), with increased risk in children having surgery (RR=2.56) or previous constipation (RR=7.38). Probiotic supplementation significantly reduced AAD (RR=0.30) and abdominal pain (RR=0.36). Lactobacillus rhamnosus GG (LGG) and L. reuteri significantly reduced AAD (RR=0.37 and 0.35) and abdominal pain (RR=0.37 and 0.24). Conclusion: AAD occurred in 20.4% of children, with increased risk at younger age, lower respiratory and urinary tract infections, intravenous treatment and previous AAD. LGG and L. reuteri reduced both AAD and associated abdominal pain.

• Food Science and Preservation
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• v.30 no.3
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• pp.538-545
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• 2023

This study aimed to assess the in vitro safety of a probiotics mixture (Lactobacillus acidophilus PBS066, Lactiplantibacillus plantarum PBS067, and Limosilactobacillus reuteri PBS072), along with its inhibitory effect on carbohydrate digestion. All three strains met the antibiotic resistance profile of the European Food Safety Authority (EFSA) guidelines. None of the strains exhibited hemolytic activity or cytotoxicity against Caco-2 cells. Strains PBS067 and PBS072 inhibited α-amylase activity, whereas all three strains suppressed α-glucosidase activity, indicating that the mixture might limit carbohydrate digestion in the gastrointestinal tract. These findings support the safety of this probiotics mixture and its potential to modulate carbohydrate metabolism in the gut.

• Journal of Animal Science and Technology
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• v.50 no.6
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• pp.807-818
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• 2008

This study was conducted to prove the optimum feeding method of Lactobacillus in broiler chickens by investigating the intestinal viability of ingested Lactobacillus and the effect of feeding levels and frequency of Lactobacillus on growth performance in broiler chickens. In experiment 1, A total of one hundred, 5 weeks old male broiler chickens(Abor Acre) were fed Lactobacillus reuteri avibro2 expressed green fluorescent protein(GFP) at 104cfu/g diet to investigate the retention time of ingested Lactobacillus in the intestine for 1 day. The percentage of Lactobacillus expressed GFP in intestinal contents was 26% at 1 day after fed Lactobacillus expressed GFP. The percentage of Lactobacillus expressed GFP in intestinal contents was decreased in length of time. In experiment 2, A total of four hundred eighty, 1-d-old male broiler chicks(Abor Acre) were randomly divided into 4 groups with 4 replicates of 30 birds each to prove the optimum feeding level of Lactobacillus. The treatments were control(free antibiotics), Lactobacillus reuteri avibro2 5.0×10cfu/mL, 5.0×103cfu/mL, and 5.0×105cfu/mL. The final body weight and body wight gain of Lactobacillus reuteri avibro2 5.0×103cfu/mL were the highest in all groups(P<0.05). Feed conversion ratio was not significantly difference among the groups. The number of intestinal lactic acid bacteria in Lactobacillus treated groups tended to be improved or significantly increased as compared to that of control(P<0.05). Protein and fat digestibility in Lactobacillus 5.0×103cfu/mL and 5.0×105cfu/mL treated groups were significantly improved(P<0.05). No significant differences were observed on the availability of dry matter and crude ash in Lactobacillus treatments compared to those of control. In experiment 3, A total of six hundred 1-d-old male broiler chicks(Abor Acre) were randomly divided into 4 groups with 4 replicates of 30 birds each and were fed Lactobacillus reuteri avibro2 at intervals of 1, 2, 3, and 5 day for five weeks. Feeding level of Lactobacillus was 5.0×103cfu/mL The final body weight and body wight gain of Lactobacillus reuteri avibro2 5.0×103cfu/mL were the highest in all groups(P<0.05). The final body weight and body weight gain were significantly increased, when Lactobacillus was fed at intervals of 1 days, or 2 days. There were no significant differences in feed intake and feed conversion ratio among the all groups. The number of intestinal lactic acid bacteria in Lactobacillus treated groups tended to be improved or significantly increased as compared to that of control(P<0.05). No significant differences were observed on the number of coliform bacteria and Salmonella of ileum and cecum. Consequently, supplemental Lactobacillus influenced positive effects on the growth performance, nutrient availability and intestinal microflora. The optimum feeding level of Lactobacillus was 5.0×103cfu/mL, and the constant feeding of Lactobacillus was effective.

• Journal of Microbiology
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• v.45 no.6
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• pp.515-520
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• 2007

Vaginal lactic acid-producing bacteria of 80 pre-menopausal women were studied by isolation on Blood and DeMan-Rogosa-Sharpe agar, PCR with group-specific primers for Lactobacillus-denaturing gradient gel electrophoresis (DGGE), and PCR with specific primers for V3 region in 16S rRNA-temporal temperature gel electrophoresis (TTGE). Conventional isolation method on media detected only one lactobacillus (Lactobacillus brevis) while TTGE detected only Lactobacillus sp. DGGE detected seven Lactobacillus species; L. coleohominis, L. crispatus, L. iners, L. reuteri, L. rhamnosus, L. vaginalis, and Leuconostoc lactis. L. acidophilus and L. gasseri, which are prevalent in Western women, were not detected in Korean women. Furthermore, L. rhamnosus, Leuc. lactis, L. coleohominis, and Weissella cibaria, which were not previously reported in the vaginal microbiota of Korean women, were detected. The five most prevalent LABs in vaginal microbiota in Korean women were L. iners, Enterococcus faecalis, L. crispatus, Leuc. lactis, and W. cibaria.

• Microbiology and Biotechnology Letters
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• v.27 no.5
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• pp.385-390
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• 1999

To investigate bile salt hydrolase activities of the bacterial strains isolated from fermented milk products, 21 strains of Lactobacillus were tested for their abilities to produced cholic acid from taurocholic and glycocholic acids. The production of cholic acid was measured by HPLC analysis during the growth in broth media for 24hrs. All strains of Lactobacillus acidophilus and L. plantarum deconjugated both taurocholate and glycocholate, whereas none strains of L. delbrueckii subsp. bulgaricus, L. casei subsp. casei, L. casei subsp. rhamnosus, L, reuteri did. L. acidophilus stains isolated from yogurts had the higher decojugation activities on glycocholate than taurocholate, however, L. acidophilus 1009 isolated from the human intestine showed the similar deconjugation activities on both taurocholate and glycocholate.

• Journal of Dairy Science and Biotechnology
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• v.26 no.2
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• pp.31-37
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• 2008

One hundred one years have passed since Metchnikoff made his first scientific contribution to probiotics study. Intestinal lactic acid bacteria (LAB) for humans are closely associated with the host's health because LAB is an important biodefense factor in preventing colonization and subsequent proliferation of pathogenic bacteria in the intestine. A probiotic is recently defined as "live microorganisms that when administered in adequate amount confer a health benefit on the host". Some species of LAB have been claimed as probiotics, such as Lactobacillus acidophilus, L. casei, L. fermentum, L. plantarum, L. reuteri, and Lactococcus lactis. For understanding the general mechanism of probiotics, this paper would explore the early studies relating to probiotics and intestinal microbiota, and briefly introduce the Prolongation of Life written by Elie Metctmikoff.

• KSBB Journal
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• v.24 no.2
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• pp.182-188
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• 2009

Lactobacillus spp., primary members of probiotics, have significant benefits for health and well-being of human. In this study Lactobacillus strains representing six species (L. paracasei KLB58, L. fermentum MS79 and KLB282, L. plantarum KLB213, L. gasseri KLB238, and L. reuteri KLB270) isolated from Korean adults were electrotransformed with plasmid pNCKH104. To determine optimal electrotransformation conditions, various conditions including cell wall weakening agent, electroporation buffer, electric field strength and time constant were tested for each strain. Overall, high transformation efficiency of approximately 2.5 ${\times}$ $10^3$ ${\sim}$ 5.5 ${\times}$ $10^4$ CFU/${\mu}g$ DNA was obtained where conditions of 0.5 M sucrose electroporation buffer, 1.8 kV pulse voltage and 5 ms time constant were applied. The common conditions developed in this study will make transformation of various Lactobacillus spp. easier than previous procedures.

• Korean Journal of Veterinary Research
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• v.55 no.2
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• pp.81-88
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• 2015

This study was conducted to isolate lactic acid bacteria (LAB) from dog intestine and identify potential probiotic strains for canine use. One hundred and one LAB were isolated from feces of 20 healthy dogs. Acid, bile, and heat resistance along with adherence to Caco-2 cells and antimicrobial activity against pathogens were examined. To analyze immunomodulative effects, the production of nitric oxide (NO), TNF-${\alpha}$, and IL-$1{\beta}$ was measured using RAW 264.7 macrophages. Additionally, RAW BLUE cells were used to evaluate nuclear factor-${\kappa}B$ (NF-${\kappa}B$) generation. Ultimately, three strains were selected as canine probiotics and identified as Lactobacillus reuteri L10, Enterococcus faecium S33, and Bifidobacterium longum B3 by 16S rRNA sequence analysis. The L10 and S33 strains showed tolerance to pH 2.5 for 2 h, 1.0% Oxgall for 2 h, and $60^{\circ}C$ for 5 min. These strains also had strong antimicrobial activity against Escherichia coli KCTC 1682, Salmonella Enteritidis KCCM 12021, Staphylococcus aureus KCTC 1621, and Listeria monocytogenes KCTC 3569. All three strains exerted better immunomodulatory effects than Lactobacillus rhamnosus GG (LGG), a well-known commercial immunomodulatory strain, based on NO, NF-${\kappa}B$, IL-$1{\beta}$, and TNF-${\alpha}$ production. These results suggested that the three selected strains could serve as canine probiotics.