• International Journal of Oral Biology
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• v.42 no.3
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• pp.107-115
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• 2017

Human malignant melanoma is an aggressive skin cancer which has been rising at a greater rate than any other cancers. Although various new therapeutic methods have been developed in previous studies, this disease has properties of high proliferation and metastasis rate which remain obstacles that have lead to a poor prognosis in patients. It has been reported that a specific Lactobacillus extract has anti-cancer and -metastasis effect in vitro and in vivo. However, previous research has not specified precisely what effect the Lactobacillus rhamnosus GG (LGG) extract has had on human malignant melanomas. In this study, we showed that the LGG extract has anti-cancer and -metastasis effects on the human malignant melanoma cell lines, A375P and A375SM. At first, it was found that, while the LGG extract affects human neonatal dermal fibroblasts slightly, it induced the dose-dependent anti-cancer effect on A375P and A375SM by a WST-1 proliferation assay. As a result of a real-time PCR analysis, the expression patterns of several genes related to cell cycle, proliferation, and apoptosis were modulating in a manner that inhibited the growth of both malignant melanoma cell lines after the treatment of the LGG extract. Furthermore, genes related to the epithelial-mesenchymal transition were down-regulated, and migration rates were also decreased significantly by the LGG extract. Our study showed that the LGG extract could be used as a potential therapeutic source.

• 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.

• Journal of Microbiology and Biotechnology
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• v.28 no.10
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• pp.1604-1613
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• 2018

Lactobacillus rhamnosus GG (LGG) is a probiotic commonly used in fermented dairy products. In this study, RNA-sequencing was performed to unravel the effects of acid stress on LGG. The transcriptomic data revealed that the exposure of LGG to acid at pH 4.5 (resembling the final pH of fermented dairy products) for 1 h or 24 h provoked a stringent-type transcriptomic response wherein stress response- and glycolysis-related genes were upregulated, whereas genes involved in gluconeogenesis, amino acid metabolism, and nucleotide metabolism were suppressed. Notably, the pilus-specific adhesion genes, spaC, and spaF were significantly upregulated upon exposure to acid-stress. The transcriptomic results were further confirmed via quantitative polymerase chain reaction analysis. Moreover, acid-stressed LGG demonstrated an enhanced mucin-binding ability in vitro, with 1 log more LGG cells (p < 0.05) bound to a mucin layer in a 96-well culture plate as compared to the control. The enhanced intestinal binding ability of acid-stressed LGG was confirmed in an animal study, wherein significantly more viable LGG cells (${\geq}2log\;CFU/g$) were observed in the ileum, caecum, and colon of acid-stressed LGG-treated mice as compared with a non-acid-stressed LGG-treated control group. To our knowledge, this is the first report showing that acid stress enhanced the intestine-binding ability of LGG through the induction of pili-related genes.

• Journal of Life Science
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• v.29 no.6
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• pp.697-704
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• 2019

This study performed to investigate the probiotic properties of lactic acid bacteria 200 strains isolated from traditional fermented foods. Based on being higher tolerance to bile salts and showing higher acid resistance, 4 LAB Strains were selected in the screening experiment; Lactobacillus plantarum SRCM 102224, Lb. plantarum SRCM102227, Lb. paracasei SRCM102329, Lb. paracasei SRCM102343. Antibacterial activity against various pathogens, acid and bile salt tolerance, hemolytic phenomenon, cell surface hydrophobicity, and antibiotic resistance were examined. Among the tested strains, SRCM 102343 (95.9%) was highly observed hydrophobicity compared to Lb. rhmanosus GG (13.4%) as control. In this study, the in vitro adhesion properties of 4 strains of LAB was investigated using human intestinal caco-2 cell cultures. SRCM102329 and SRCM102343showed higher adherence to caco-2 cells than Lb. rhamnosus GG. The antibacterial activities of 4 strains LAB were investigated. the 3 strains showing strongly antimicrobial activity against Escherichia coli ATCC10798, Staphylococcus aureus KCCM11593, Listeria invanovii KCTC3444, Bacillus cereus ATCC11778 and S. enterica serovar. Typhi KCTC1926. These results suggest that selected strains have good probiotic potential for application in functional foods.

• Preventive Nutrition and Food Science
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• v.7 no.2
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• pp.168-173
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• 2002

Gastrointestinal infections kill over two million people each year, and pathogen contamination of livestock causes many cases of food poisoning. Two candidate intestinal probiotic strains, L. rhamnosus GR-1 and L. fermentum RC-14 were found to inhibit the growth of Salmonella typhi, Shigella dysenteriae, E. coli O157:H7, Listeria monocytogenes, L. innocua, Enterococcus faecalis, and Bacteroides fragilis. In a series of mouse experiments, L. rhamosus GR-1 and L rhamnosus GG protected against S. typhimurium infection and translocation to the liver and spleen, reduced mortality and induced intestinal phagocytic and immunoglobulin responses. In a second series of experiments, the combination of L. rhamnosus GR-1 and L. fermentum RC-14 was superior to L. rhamnosus GG and placebo in protecting the mice from the lethal effect of salmonella. In summary, the use of combinations of probiotic lactobacilli as dietary supplements or foods could be considered for people at high risk of salmonella intestinal infection. Given the post-infection complications that can arise, such natural methods warrant further exploration especially given the increasing problem of antibiotic resistance and the lack of alternative measures available to many developing countries.

• Journal of Life Science
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• v.20 no.12
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• pp.1882-1888
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• 2010

To develop probiotics, a kind of Lactobacillus sp. was isolated from infant feces. The bacterium was identified as Lactobacillus rhamnosus through 16S rDNA sequence analysis. The strain was a facultative anaerobe which grew better in aerobic conditions. The bacterium lowered the pH of the culture solution down to 2.4 during 48 hr in the MRS medium. The strain inhibited the growth of 6 pathogens - S. aureus, L. monocytogens, S. typhimurium, E. coli O-157, V. parahaemolyticus and P. aeruginosa. When the Lactobacillus were fed to chickens, along with commercial feed, for one month, amounts of $H_2S$ and $NH_3$ in the feces of the chicken decreased to 50% and 70%, respectively, compared to those of control group chickens. Amounts of other bad smells such as $(CH_3)SH$, $(CH_3)_2S$ and $(CH_3)_2S_2$ were not much different in the Lactobacillus-fed chickens compared to the control group. On the other hand, egg weights of the chickens fed Lactobacillus were higher by about $5{\pm}1\;g$ than those in the control group.

• Food Science of Animal Resources
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• v.35 no.5
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• pp.615-621
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• 2015

Lactobacillus plantarum FH185 was isolated from the feces of healthy adults. In our previous study, L. plantarum FH185 was demonstrated that it has anti-obesity effect in the in vitro and in vivo test. In order to determine its potential for use as a probiotic, we investigated the physiological characteristics of L. plantarum FH185. The optimum growth temperature of L. plantarum FH185 was 40℃. L. plantarum FH185 showed higher sensitivity to novobiocin in a comparison of fifteen different antibiotics and showed higher resistance to polymyxin B and vancomycin. It also showed higher β-galactosidase and N-acetyl-β-glucosaminidase activities. Moreover, it was comparatively tolerant to bile juice and acid, and inhibited the growths of Salmonella Typhimurium and Staphylococcus aureus with rates of 44.76% and 53.88%, respectively. It also showed high adhesion activity to HT-29 cells compared to L. rhamnosus GG.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.3
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• pp.430-434
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• 2003

In vivo antagonistic effect of Lactobacillus helveticus CU 631 and Lactobacillus spp. against typical enteritis causing pathogen Salmonella enteritidis KU 101 have been determined, which showed an increase in survival rate and the decline in viable cell numbers of pathogen in liver and spleen at sacrifice. A signifcant difference in the antagonistic effect against KU 101 were observed, which was species and/or strain dependent of Lactobacillus (p<0.01), the survival rate of the mice in the Salmonella infection by feeding L. helveticus CU 631 has been shown to be 157%, whereas those of L. rhamnosus GG ATCC 53103, L. acidophilus ATCC 4356, L. johnsonii C-4 were 137%, 132%, 119% respectively on the basis of lactobacilli non-associated control KU101 fed mice to be 100%. Viable cells of S. enteritidis KU101 in the liver and in the spleen at sacrifice were decreased in Lactobacillus spp. fed group with no significant difference. The higher level of total secretory IgA concentration in the intestinal fluid of lactobacilli fed mice than control mice have been observed. In vitro antagonistic activity of Lactobacillus spp. against KU101 have been determined, a prominent antagonistic activity of CU 631 against KU 101 were demonstrated.

• Journal of Life Science
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• v.24 no.11
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• pp.1231-1237
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• 2014

The objective of this study was to evaluate the safety and functional properties of four potential probiotic strains isolated from Kimchi, traditional Korean fermented vegetables. Based on being higher tolerance to bile salts and showing higher acid resistance or hydrophobic properties, one Lactobacillus arizonensis strain (BCNU 9032) and three L. brevis strains (BCNU 9037, BCNU 9098 and BCNU 9101) were selected in the screening experiment. All strains can survived up to 99% after 3h culture in pH 2.5 and resistant to 1% bile salts. These strains also showed good antimicrobial activities against a number of food borne pathogens, especially against Escherichia coli and Shigella sonnei. The ability to lower cholesterol levels of L. arizonensis BCNU 9032 and L. brevis 9037 were demonstrated by bile salt hydrolytic activity and cholesterol assimilation tests. Moreover, L. brevis BCNU 9098 and BCNU 9101 showed higher adherence to Caco-2 cells (12.76 and 11.86%, respectively) than Lactobacillus rhamnosus GG, a commercial probiotic strain used worldwide. The results suggest that these strains could be used as probiotics.

• Journal of Dairy Science and Biotechnology
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• v.35 no.4
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• pp.221-231
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• 2017

This study aimed to investigate the physiological characteristics and anti-obesity effects of a newly isolated bacterium, Lactobacillus plantarum K6. L. plantarum K6 showed good ${\alpha}-amylase$ inhibitory activity ($96.78{\pm}3.29%$), ${\alpha}-glucosidase$ inhibitory activity ($92.55{\pm}9.62%$), and lipase inhibitory activity ($85.17{\pm}0.79%$), and the strain inhibited the adipocyte differentiation of 3T3-L1 cells ($27.4{\pm}1.4%$) when present at a concentration of $100{\mu}g/mL$. L. plantarum K6 was isolated from kimchi and its physiological characteristics were investigated. A comparison of the sensitivity of the isolate to 15 different antibiotics showed that L. plantarum K6 is highly sensitive to erythromycin and highly resistant to vancomycin, ampicillin, and polymyxin B. This strain also showed high arylamidase and ${\beta}-galactosidase$ activities. Moreover, it was relatively tolerant to bile acid and low pH, and displayed resistance to Escherichia coli, Salmonella Typhimurium, Listeria monocytogenes, and Staphylococcus aureus, with rates of 51.8%, 42.4%, 61.6%, and 54.9%, respectively. No bio genic amines were produced. L. plantarum K6 also showed high adhesion activity to HT-29 cells compared to L. rhamnosus GG. These results demonstrate that Lactobacillus plantarum K6 has potential as a probiotic with anti-obesity effects.