• Journal of Microbiology and Biotechnology
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• v.15 no.3
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• pp.616-625
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• 2005

It is likely that maltose could provide a good substrate for the bacteria in the intestine, when the pathogenic bacteria invade and colonize in human gut. For better understanding of this organism's maltose metabolism, a mutant that was not able to grow with maltose as a sole carbon source was screened from a library of mutants constructed by a random transposon mutagenesis. By a transposon-tagging method, malPQ genes encoding a maltodextrin phosphorylase and a 4-${\alpha}$-glucanotransferase, were identified and cloned from Vibrio vulnificus. The deduced amino acid sequences of malPQ from V. vulnificus were 48 to $91\%$ similar to those of MalP and MalQ reported from other Enterobacteriaceae. Functions of malPQ genes were assessed by the construction of mutants whose malPQ genes were inactivated by allelic exchanges. When maltose was used as the sole carbon source, neither malP nor malQ mutant was able to grow to a substantial level, revealing that the MalP and MalQ are the only enzymes for metabolic utilization of maltose. The malQ mutant exhibited decreased adherence toward intestinal epithelial cells in vitro, but there was no difference in the $LD_{50}s$ of the wild-type and the malQ mutant in mice. Therefore, it appears that MalQ is less important in the pathogenesis of V. vulnificus than would have been predicted by considering maltose as a most common sugar in the intestine, but not completely dispensable for virulence in mice.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1414-1417
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• 2000

This study was to investigate effects of the supplementation of the different lactic acid bacteria[Streptococcus thermophilus KCTC 2185 culture group(ST), autoclaved Streptococcus thermophilus KCTC 2185 culture(STS), Lactobacillus acidophilus ATCC 4356 culture group(LA) and autoclaved Lactobacillus acidophilus ATCC 4356(LAS)] on suppression of aluminum accumulation in organs of rats fed with the diet containing $250\;{\mu}g/g$ aluminum sulfate for 4 weeks. Amount of aluminum accumulation in the control rat was in order of bone>lung>heart>large intestine>kidney>liver>brain>small intestine. Effects of reduction of aluminum accumulation by feeding of the four difference fermented milk were in order of LA group>LAS group>ST group>STS group. ST and LA both were more effective than STS and LAS. Ultimately fermented milk was useful in reduction of toxication by accumulating of aluminum in vivo.

• Journal of Microbiology and Biotechnology
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• v.12 no.4
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• pp.657-663
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• 2002

Probiotics have been suggested to improve gastrointestinal health in humans. To investigate the effects of Bacillus polyfermenticus SCD administration on fecal microflora and putrefactive metabolites in humans, Bacillus polyfermenticus SCD (4.00${\times}$10$\sub$5/ CFU/mg) was administrated to ten healthy subjects (5 men and 5 women, average age 24 years) three times a day for 2 weeks. Fecal samples were collected before (1st and 2nd weeks, control), during (3rd and 4th weeks), and 2 weeks after the administration. The fo11owing microbial groups were evaluated in the feces: aerobic and anaerobic bacteria, Bacillus polyfermenticus SCD, Lactobacillus, Bifidobacterium, total lactic acid bacteria, Salmonella, Clostridium, Clostridium perfringens, Eubacterium, Staphylococcus, Coliform bacteria, Pseudomunas, and Yeast. Fecal concentrations of total aerobic bacteria (p<0.05, p<0.01, 3rd and 4th weeks), total lactic acid bacteria (p<0.01, 3rd, 4th and 5th weeks), and Bifidobacteria (p<0.05, 4th and 5th weeks) were significantly increased in all subjects, compared to the control, from the 3rd week after the administration of the products. Clostridium (p<0.01, 4th week), Clostridium perfringens (p<0.05, p<0.01, 3rd and 4th weeks), and coliform (p<0.01,5th week) were significantly reduced from the 3rd week of administration. No significant changes in the fecal concentrations of Pseudomonas, Lactobacillus, Eubacterium, Staphylococcus, yeast, and total anaerobes were observed. Six weeks after the administration, the concentration of all rnicroorganlsrns returned to the basal level. Bacillus polyfermenticus SCD was significantly maintained from the 3rd week to 6th week of the study. Despite the absence of a statistical significance, the putrefactive metabolites (ammonia, indole, skatole, and $\rho$-cresol) and the pH value tended to be lower during and after the test periods than the base line. These results show that this probiotic preparation is able to colonize the intestine, and suggest that it may be useful as a beneficial probiotic in humans.

• Journal of Life Science
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• v.25 no.2
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• pp.164-173
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• 2015

To investigate the effect of lactic acid bacteria on the heavy metal adsorption from internal organs and blood, lactic acid bacteria were isolated from human feces. Some strains resistant to heavy metals were selected by incubation in agar media containing each of chrome and cadmium salts. Among them, a strain named KP-3 was ultimately chosen due to its higher growth rate in selective broth medium containing the heavy metals at the concentration of 0.01%. The strain was identified as Lactobacillus sp. based on its morphological, cultural and physiological characteristics. For evaluating the ability to prevent accumulation of heavy metals by selected Lactobacillus sp. strain in vivo, Sprague Dawley rats were fed with heavy metal salts (cadmium, chrome and lead) with or without cultured whole cells for 7 days. The amounts of heavy metals accumulated in liver, kidney and blood were analyzed. As a result, chrome was accumulated to kidney mostly, and lead was frequently found in liver and kidney. Experimental group (rats fed with lactic acid bacteria) showed less accumulation of heavy metal than control group (rats fed with saline solution). The inhibition rates of heavy metal accumulation were calculated to 41.8% (Cd), 33.4% (Cr) and 44.2% (Pb). Especially, feeding lactic acid bacteria strongly reduced accumulation of cadmium in blood. The results showed that feeding Lactobacillus sp. KP-3 could prevent the bioaccumulation of heavy metals in the living body.

• Korean Journal of Veterinary Research
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• v.51 no.4
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• pp.281-288
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• 2011

Lactobacillus salivarius JWS 58 (JWS 58) and Lactobacillus plantarum JWS 1354 (JWS 1354) are isolated from duck intestine and have ability to produce bacteriocin. The objective of this study was to evaluate the immunomodulatory effects of JWS 58 and JWS 1354. The nitric oxide (NO) and cytokines (IL-$1{\beta}$ and TNF-${\alpha}$) were measured in C57BL/6 mouse peritoneal macrophages to determine immune enhancing effects of JWS 58 and JWS 1354. A Listeria (L.) monocytogenes challenge mice model was used to evaluate immune enhancement ability of JWS 58 and JWS 1354 in vivo. The results showed that JWS 58 and JWS 1354 increased the production of NO or cytokines by peritoneal macrophages and that oral administration of viable probiotic strains in mice elicited the immuno-modulatory effect upon L. monocytogenes challenge. JWS 1354 showed stronger immune enhancing effects than JWS 58. Collectively, this study demonstrated that Lactobacillus strain JWS 58 and JWS 1354 possess immune enhancing effect. Furthermore, two stains are expected to use feed supplement to prevent diseases by pathogenic bacteria through releasing bacteriocin and enhancing host immune responses in animal.

• Microbiology and Biotechnology Letters
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• v.30 no.4
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• pp.380-387
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• 2002

To investigate the effects of xylooligosaccharides on the in vitro growth of intestinal bacteria, various species were cultivated individually on the m-PYF medium containing a carbon source (0.5% w/v) such as xylooligosaccharides, isomaltooligosaccharides, fructooligosaccharides and sucrose, respectively. The health-promoting microorganisms such as Bifidobacterium bifidum, Bifidobacterium infantis, Bifidobacterium longum, Lactobacillus casei and Lactobacillus acidophilus grew more effectively by xylooligosaccharides than by other carbon source, though xylooligosaccharides inhibited the growth of Clostridium perfringens, Bacteroides fragilis, Escherichia coli, Staphylococcus aureus and Salmonella typhumurium. At the mixed culture xylooligosaccharides exerted a preferential stimulatory effects on numbers of the health-promoting microorganisms, while xylooligosaccharides inhibited populations of potential pathogens at relatively low level. Xylooligosaccharides also maintained the acidity of culture with Streptococcus mutans, caries-inducing bacteria, over pH 5.0. These results suggest that xylooligosaccharides selectively promote the growth of the health-promoting microorganisms in human intestine and prevent caries by inhibiting acid production from Streptococcu mutans.

• 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.

• Journal of fish pathology
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• v.25 no.2
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• pp.67-76
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• 2012

Two bacteria strains were isolated from emaciated olive flounder (Paralichthys olivaceus) in aquafarm and were identificated as Vibrio harveyi (JV1) and Edwardsiella tarda (JE1), respectively. In the challenge experiments, we found 100% cumulative mortalities in all of olive flounder injected with JV1, JE1 or JV1+JE1 within eleven days after the injection. Two bacteria strains were reisolated from dead fish and were analyzed using the PCR method. In the physilogical analysis, the hematocrit, AST, ALT and cholesterol levels in experimental groups were increased significantly compared to those in control group, but the glucose, total protein and triglyceride levels were significantly decreased. Additionally, the lysozyme activity in the blood serum was decreased. The histopathological observations of the intestine showed that all groups had detachment and destruction of epithelial tissues except for the control group.

• Food Science of Animal Resources
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• v.32 no.1
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• pp.31-39
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• 2012

The purpose of this study was to isolate bacteriocin-producing bacteria with antagonistic activities against pathogens from the intestines of pigs for probiotic use. Lactobacillus sp. AP 116 possessing antimicrobial property was selected from a total of 500 isolates. The AP 116 strain showed a relatively broad spectrum of inhibitory activity against Listeria monocytogenes, Clostridium perfringens, Pediococcus dextrinicus, and Enterococcus strains using the spot-on-lawn method. Bacteriocin activity remained unchanged after 15 min of heat treatment at $121^{\circ}C$ and exposure to organic solvents; however, it diminished after treatment with proteolytic enzymes. Maximum production of bacteriocin occurred at $34^{\circ}C$ when a pH of 6.0 was maintained throughout the culture during fermentation. According to a tricine SDS-PAGE analysis, the molecular weight of the bacteriocin was approximately 5 kDa. The isolate tolerated bile salts and low pH, and also induced nitric oxide (NO) in mouse peritoneal macrophages. Bacteriocin and bacteriocin-producing bacteria, such as Lactobacillus sp. AP 116, could be potential candidates for use as probiotics as an alternative to antibiotics in the pig industry.

• Korean Journal of Organic Agriculture
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• v.10 no.4
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• pp.47-60
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• 2002

'Probiotics' as a live microbial feed supplementation which beneficially affects the host animal by improving its microbial balance and it is known to as a substitue for antibiotics in livestock feed industry. Lactic acid bacteria as a Lactobacillus sp. is formed acid and decrease pH in gastro-intestine that is result in suppress harmful microorganism. Lactobacillus sp. also produces vitamin and a variety amino acids. Yeast as a saccharomyces sp. secretes digestive enzymes, decreases ammonia emission and increases feed palatability by alcohol and glutamic acid. The effects of dietary probiotics in monogastric animals that improve weight gain and feed efficiency ratio and decrease diarrhea accurence frequency in pigs. Also, probiotics increase egg production ratio and beneficial microorganisms in laying hens. In broiler, they have more gain weight and lower blood cholesterol concentrations by probiotics. However, the other study reported probiotics supplementation in animal diets has no effect on ADG, G/F or performance. Thus, future study in these area will allow for more efficient use of the probiotics, selection of more superior microorganism and development of more efficient environment-friendly probiotics like a photosynthetic bacteria.