• Journal of Veterinary Clinics
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• v.28 no.5
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• pp.516-518
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• 2011

A survey was conducted to examine the normal intestinal bacterial flora of captive Oriental white storks (Ciconia boyciana) maintained at the Korea Institute of Oriental White Stork Rehabilitation Research, Cheongwon, South Korea. From the cloaca of 44 healthy storks, 44 fecal samples were collected and cultured under aerobic and anaerobic conditions. The 16S ribosomal RNA gene sequences and the heat shock protein 60 gene were cloned and sequenced for bacterial identification. Under aerobic conditions, Enterococcus faecalis, Escherichia coli, Bacillus spp., Enterococcus avium, Enterococcus gallinarum, Pseudomonas spp., Alcaligenes spp., Enterobacter spp., Corynebacterium spp., and Proteus mirabilis were identified. Under anaerobic conditions, E. coli, Clostridium tertium, En. faecalis, and P. mirabilis were identified. E. coli, En. faecalis, or both were isolated from all samples. These results will add to the information available on this stork species and help for the interpretation of fecal culture results.

• Toxicological Research
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• v.26 no.4
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• pp.301-313
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• 2010

Growth promoters including hormonal substances and antibiotics are used legally and illegally in food producing animals for the growth promotion of livestock animals. Hormonal substances still under debate in terms of their human health impacts are estradiol-$17\beta$, progesterone, testosterone, zeranol, trenbolone, and melengestrol acetate (MGA). Many of the risk assessment results of natural steroid hormones have presented negligible impacts when they are used under good veterinary practices. For synthetic hormonelike substances, ADIs and MRLs have been established for food safety along with the approval of animal treatment. Small amounts of antibiotics added to feedstuff present growth promotion effects via the prevention of infectious diseases at doses lower than therapeutic dose. The induction of antimicrobial resistant bacteria and the disruption of normal human intestinal flora are major concerns in terms of human health impact. Regulatory guidance such as ADIs and MRLs fully reflect the impact on human gastrointestinal microflora. However, before deciding on any risk management options, risk assessments of antimicrobial resistance require large-scale evidence regarding the relationship between antimicrobial use in food-producing animals and the occurrence of antimicrobial resistance in human pathogens. In this article, the risk profiles of hormonal and antibacterial growth promoters are provided based on recent toxicity and human exposure information, and recommendations for risk management to prevent human health impacts by the use of growth promoters are also presented.

• Korean Journal of Microbiology
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• v.27 no.2
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• pp.155-161
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• 1989

Lactobacillus sporogenes was treated with N-methyl-N'-nitro-N-nitrosoguanidine (NTG) to obtain resistant mutants to rifampicin. Fifty-eight strains of the NTG-induced mutants showed distinct resistance to rifampicin and nine mutants were selected for further studies. They also exhibited identical characteristics with the parent Lactobacillus sporogenes when they were tested for spore formation, acid formation and growth inhibition of E. coli. From in vitro test it was identified that rifampicin is not inactivated by certain factors of the rifampicin resistant mutants. It is suggested that they can be utilized as efficient normalizing agents for human intestinal flora when they are simultaneously taken with rifampicin

• Journal of Dairy Science and Biotechnology
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• v.18 no.1
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• pp.47-60
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• 2000

Over decades of work, the probiotic research has grown rapidly with a number of new cultures, which is claimed a variety of benefit. However, many of the specific effects attributed to the ingestion of probiotics remain convoluted and scientifically unsubstantiated. Accordingly, the scientific community faces a greater challenge and must objectively seek cause and effect relationships for many potential and currently investigated probiotic species. Rational selection and design of probiotics remains an important challenge and will require a solid information about the physiology and genetics of candidate strains relevant to their intestinal roles, functional activities, and interaction of with other resident micro flora. As far as beneficial culture of lactic acid bacteria (LAB) is concerned, simple, cost-effective, and exact identification of candidate strains is of foremost importance among others. Until recently, the relatedness of bacterial isolates has been determined sorely by testing for one or several phenotyphic markers, using methods such as serotyping, phage-typing, biotyping, and so forth. However, there are problems in the use of many of these phenotype-based methods. In contrast, some of newer molecular typing methods involving the analysis of DNA offer many advantages over traditional techniques. These DNA-based methods have the greater discriminatory power than that of phenotypic procedures. This review focuses on the importance and the basis of molecular typing methods along with some considerations on de-sign and selection of probiotic culture for human consumption.

• Microbiology and Biotechnology Letters
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• v.46 no.4
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• pp.334-345
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• 2018

Spore-forming Bacillus species are commercially available probiotic formulations for application in humans. They have health benefits and help prevent disease in hosts by combating entero-pathogens and ameliorating antibiotic-associated diarrhea. However, the molecular and cellular mechanisms of these benefits remain unclear. Here, we report the draft genome of a potential probiotic strain of Bacillus clausii B106. We mapped and compared the probiotic profile of B106 with other reference genomes. The draft genome analysis of B106 revealed the presence of ADI pathway genes, indicating its ability to tolerate acidic pH and bile salts. Genes encoding fibronectin binding proteins, enolase, as well as a gene cluster involved in the biosynthesis of exopolysaccharides underscored the potential of B106 to adhere to the intestinal epithelium and colonize the human gut. Genes encoding bacteriocins were also detected, indicating the antimicrobial ability of this isolate. The presence of genes encoding vitamins, including Riboflavin, Folate, and Biotin, also indicated the health-promoting ability of B106. Resistance of B106 to multiple antibiotics was evident from the presence of genes encoding resistance to chloramphenicol, ${\beta}$-lactams, Vancomycin, Tetracycline, fluoroquinolones, and aminoglycosides. The findings indicate the significance of B. clausii B106 administration during antibiotic treatment and its potential value as a probiotic strain to replenish the health-promoting and disease-preventing gut flora following antibiotic treatment.

• Journal of Animal Science and Technology
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• v.63 no.5
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• pp.1207-1210
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• 2021

Lactobacillus amylovorus are known to exist in the intestinal flora of healthy cattle or pigs. The L. amylovorus strain 1394N20 was isolated from the feces of the Hanwoo calf (Bos taurus coreanae). The genome of strain 1394N20 consists of a single circular chromosome (2,176,326 bp) with overall guanine + cytosine content of 37.8 mol%. Moreover, 2,281 protein-coding sequences, 15 rRNAs, and 65 tRNAs genes were identified in the chromosome based on the results of annotation. The bacterium has a gene encoding endoglucanase, an enzyme that hydrolyzes the 1,4-β-D-glycosidic linkages in cellulose, hemicellulose, lichenin, and cereal β-D-glucans. Genomic sequencing of L. amylovorus strain 1394N20 reveals the immense potential of the strain as a probiotic with nutrient digestibility.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.6
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• pp.856-864
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• 2019

Objective: The objective of this study was to investigate effects of mixed organic acids (MOA) on nutrient digestibility, volatile fatty acids composition and intestinal microbiota in growing-finishing pigs fed high wheat bran diet. Methods: Six crossbred barrows ($Duroc{\times}Landrace{\times}Yorkshire$), with an average body weight $78.8{\pm}4.21kg$, fitted with T-cannulas at the distal ileum, were allotted to a double $3{\times}3$ Latin square design with 3 periods and 3 diets. Each period consisted of a 5-d adjustment period followed by a 2-d total collection of feces and then a 2-d collection of ileal digesta. The dietary treatments included a corn-soybean-wheat bran basal diet (CTR), mixed organic acid 1 diet (MOA1; CTR+3,000 mg/kg OA1), mixed organic acid 2 diet (MOA2; CTR+2,000 mg/kg OA2). Results: Pigs fed MOA (MOA1 or MOA2) showed improved (p<0.05) apparent total tract digestibility (ATTD) of gross energy, dry matter and organic matter, and pigs fed MOA2 had increased (p<0.05) ATTD of neutral detergent fiber compared to CTR. Dietary MOA supplementation decreased (p<0.05) pH value, and improved (p<0.01) concentrations of lactic acid and total volatile fatty acids (TVFA) in ileum compared to CTR. Pigs fed MOA showed higher (p<0.05) concentration of acetic acid, and lower (p<0.05) content of formic acid in feces compared to CTR. Pigs fed MOA1 had increased (p<0.05) concentration of TVFA and butyric acid in feces. Pigs fed MOA1 showed higher concentration of Lactobacillus and lower concentration of Escherichia in feces compared to CTR. Conclusion: Dietary supplementation of MOA 1 or 2 could improve nutrients digestibility, TVFA concentration and intestinal flora in growing-finishing pigs fed high fiber diet.

• Korean Journal of Food Science and Technology
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• v.41 no.6
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• pp.673-680
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• 2009

This study was conducted to screen for plant food materials that improve human intestinal microflora, especially microorganisms associated with obesity. Among 30 tested plant food materials, the extract of Schizandra chinensis inactivated Eubacterium limosum, Bacteroides fragilis and Clostridium spp. Additionally, S. chinensis extract was also found to have a growth-promoting effect on Bifidobacterium spp.. The antimicrobial activity and antioxidant activity of the water extract did not decrease in respond to heating. Additionally, the water extract of S. chinensis did not show a toxic effect on the growth of Caco-2 cells. In vivo feeding tests were performed to investigate the influence of extract on the intestinal microflora in rats. Although the extract did not reduce obesity induced by a high fat diet, it led to significant increase in the population of Bifidobacterium spp. and a decrease in the population of Clostridium spp. in rats. Taken together, these results indicate that S. chinensis could be useful as a functional food component to control intestinal microbial flora.

• Korean Journal of Agricultural Science
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• v.44 no.4
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• pp.558-565
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• 2017

This study was conducted to determine the effect of inoculation of microorganism isolated from pig feces on nutrient contents of fermented hulless barley. The microbial flora in feces of a total of four crossbred piglets ($Landrace{\times}Yorkshire{\times}Duroc$) was analyzed by 16s rRNA sequencing. The most abundant strain was then selected for fermentation of hulless barley. Lactobacillus plantarum (L. plantarum) was dominant (64.56%) in intestinal microbial flora in the pig feces. The selected candidate strain showed significantly higher survival rate at pH 7 than at pH 2.5 and 3.0 (p < 0.05). Incubated culture containing the candidate strain showed an increased growth rate with lower pH levels after 7.5 h incubation compared to initial incubation period (p < 0.05). When compared with commercial multiple probiotics which were used as control, the selected strain showed faster growth rate at 5 h post-incubation (p < 0.05). During the fermentation period, neither inoculated nor non-inoculated control hulless barley showed any change in pH value. Crude fat, fiber and ash contents were lower (p < 0.05) in hulless barley inoculated by the selected strain compared to control. However, moisture, energy, NDF and ADF were not affected by the inoculation of strain or fermentation period. Lactic acid was increased and acetic acid was decreased in the hulless barley inoculated with the selected strain during the fermentation period (p < 0.05). Taken together, our results suggest that L. plantarum derived from the pigs could be utilized as a new microorganism for manufacturing fermented feed stuffs.

• Journal of Microbiology and Biotechnology
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• v.27 no.8
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• pp.1392-1400
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• 2017

Galactooligosaccharides (GOSs) are known to be selectively utilized by Bifidobacterium, which can bring about healthy changes of the composition of intestinal microflora. In this study, ${\beta}-GOS$ were synthesized using bifidobacterial ${\beta}-galactosidase$ (G1) purified from recombinant E. coli with a high GOS yield and with high productivity and enhanced bifidogenic activity. The purified recombinant G1 showed maximum production of ${\beta}-GOSs$ at pH 8.5 and $45^{\circ}C$. A matrix-assisted laser desorption ionization time-of-flight mass spectrometry analysis of the major peaks of the produced ${\beta}-GOSs$ showed MW of 527 and 689, indicating the synthesis of ${\beta}-GOSs$ at degrees of polymerization (DP) of 3 and DP4, respectively. The trisaccharides were identified as ${\beta}-{\text\tiny{D}}$-galactopyranosyl-($1{\rightarrow}4$)-O-${\beta}-{\text\tiny{D}}$-galactopyranosyl-($1{\rightarrow}4$)-O-${\beta}-{\text\tiny{D}}$-glucopyranose, and the tetrasaccharides were identified as ${\beta}-{\text\tiny{D}}$-galactopyranosyl-($1{\rightarrow}4$)-O-${\beta}-{\text\tiny{D}}$-galactopyranosyl-($1{\rightarrow}4$)-O-${\beta}-{\text\tiny{D}}$-galactopyranosyl-($1{\rightarrow}4$)-O-${\beta}-{\text\tiny{D}}$-glucopyranose. The maximal production yield of GOSs was as high as 25.3% (w/v) using purified recombinant ${\beta}-galactosidase$ and 36% (w/v) of lactose as a substrate at pH 8.5 and $45^{\circ}C$. After 140 min of the reaction under this condition, 268.3 g/l of GOSs was obtained. With regard to the prebiotic effect, all of the tested Bifidobacterium except for B. breve grew well in BHI medium containing ${\beta}-GOS$ as a sole carbon source, whereas lactobacilli and Streptococcus thermophilus scarcely grew in the same medium. Only Bacteroides fragilis, Clostridium ramosum, and Enterobacter cloacae among the 17 pathogens tested grew in BHI medium containing ${\beta}-GOS$ as a sole carbon source; the remaining pathogens did not grow in the same medium. Consequently, the ${\beta}-GOS$ are expected to contribute to the beneficial change of intestinal microbial flora.