• Food Science of Animal Resources
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• v.36 no.5
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• pp.635-640
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• 2016

Lactobacillus acidophilus n.v. Er2 317/402 strain Narine is known as a health beneficial functional probiotic culture and supplementary source of nutrition for newborns. In this study, in vitro antimicrobial activities of Narine-lyophilized (Narine-L), Narine-heat treated (Narine-HT), and Narine crude cell-free extract (Narine-CCFE) were evaluated against pathogen Cronobacter sakazakii (C. sakazakii) in agar as well as in a reconstituted powdered infant formula (RPIF) model. Inhibition zones of 30 mg Narine-L and Narine-HT were both 150 U, whereas inhibition zone of 30 mg Narine-CCFE was 200 U. Narine-L (1 g) and Narine-HT (1 g) were added to 10 mL of artificially contaminated RPIF, respectively, containing 100 μL of C. sakazakii (1.62×10⁸ colony forming unit (CFU)/mL). After treatment with Narine-L and Narine-HT for 3 h and 6 h at 37℃, less than ≤107 CFU/mL of C. sakazakii was detected in RPIF. Without Narine-L and Narine-HT treatment, the population of C. sakazakii increased up to 5.36×10⁹ CFU/mL after 6 h. Examination by transmission electron microscopy confirmed C. sakazakii cells were damaged by Narine-CCFE. Thus, employing Narine culture as a natural and safe bio-preservative may protect infants from C. sakazakii.

• Restorative Dentistry and Endodontics
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• v.42 no.1
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• pp.54-59
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• 2017

Objectives: The purpose of this study was to compare the antibacterial activity of urushiol against Enterococcus faecalis (E. faecalis) to that of NaOCl. Materials and Methods: The canals of thirty two single rooted human teeth were instrumented with Ni-Ti files (ProTaper Next X1, X2, X3, Dentsply). A pure culture of E. faecalis ATCC 19433 was prepared in sterile brain heart infusion (BHI) broth. The teeth were submerged in the suspension of E. faecalis and were incubated at $37^{\circ}C$ for 7 days to allow biofilm formation. The teeth were randomly divided into three experimental groups according to the irrigant used, and a negative control group where no irrigant was used (n = 8). Group 1 used physiologic normal saline, group 2 used 6% NaOCl, and group 3 used 10 wt% urushiol solution. After canal irrigation, each sample was collected by the sequential placement of 2 sterile paper points (ProTaper NEXT paper points, size X3, Dentsply). Ten-fold serial dilutions on each vials, and 100 µL were cultured on a BHI agar plate for 8 hours, and colony forming unit (CFU) analysis was done. The data were statistically analyzed using Kruskal-Wallis and Mann-whitney U tests. Results: Saline group exhibited no difference in the CFU counts with control group, while NaOCl and urushiol groups showed significantly less CFU counts than saline and control groups (p < 0.05). Conclusions: The result of this study suggests 10% urushiol and 6% NaOCl solution had powerful antibacterial activity against E. faecalis when they were used as root canal irrigants.

• Osong Public Health and Research Perspectives
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• v.8 no.6
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• pp.389-396
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• 2017

Objectives: To circumvent the limitations of the current golden standard method, colony-forming unit (CFU) assay, for viability of Bacille Calmette-$Gu{\acute{e}}rin$ (BCG) vaccines, we developed a new method to rapidly and accurately determine the potency of BCG vaccines. Methods: Based on flow cytometry (FACS) and fluorescein diacetate (FDA) as the most appropriate fluorescent staining reagent, 17 lots of BCG vaccines for percutaneous administration and 5 lots of BCG vaccines for intradermal administration were analyzed in this study. The percentage of viable cells measured by flow cytometry along with the total number of organisms in BCG vaccines, as determined on a cell counter, was used to quantify the number of viable cells. Results: Pearson correlation coefficients of FACS and CFU assays for percutaneous and intradermal BCG vaccines were 0.6962 and 0.7428, respectively, indicating a high correlation. The coefficient of variation value of the FACS assay was less than 7%, which was 11 times lower than that of the CFU assay. Conclusion: This study contributes to the evaluation of new potency test method for FACS-based determination of viable cells in BCG vaccines. Accordingly, quality control of BCG vaccines can be significantly improved.

• Journal of Veterinary Science
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• v.21 no.6
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• pp.87.1-87.11
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• 2020

Background: A new, extended long-acting tilmicosin (TLAe) preparation was tested against intramammary ceftiofur (CEF) using a non-inferiority trial model during dry-cow therapy (DCT) in a farm with high bovine population density and deficient hygiene application. Objectives: To evaluate the possibility that TLAe administered parenterally can achieve non-inferiority status compared to CEF administered intramammary for DCT. Methods: Cows were randomly assigned to TLAe (20 mg/kg subcutaneous; n = 53) or CEF (CEF-HCl, 125 mg/quarter; n = 38 cows) treatment groups. California mastitis testing, colony-forming unit assessment (CFU/mL), and number of cases positive for Staphylococcus aureus were quantified before DCT and 7 d after calving. A complete cure was defined as no bacteria isolated; partial cure when CFU/mL ranged from 150 to 700, and cure-failure when CFU/mL was above 700. Results: TLAe and CEF had overall cure rates of 57% and 53% (p > 0.05) and S. aureus cure rates of 77.7% and 25%, respectively (p < 0.05). The pathogens detected at DCT and 7 days after calving were S. aureus (62.71% and 35.55%), Staphylococcus spp. (22.03% and 35.55%), Streptococcus uberis (10.16% and 13.33%), and Escherichia coli (5.08% and 15.55%). Non-inferiority and binary logistic regression analyses revealed a lack of difference in overall efficacies of TLAe and CEF. Apart from S. aureus, S. uberis was the predominant pathogen found in both groups. Conclusions: This study is the first successful report of parenteral DCT showing comparable efficacy as CEF, the gold-standard. The extended long-term pharmacokinetic activity of TLAe explains these results.

• Korean Journal of Agricultural Science
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• v.49 no.4
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• pp.933-944
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• 2022

Fire blight in apple and pear orchards, caused by Erwinia amylovora, is a global problem. Ongoing outbreaks have occurred since 2015. In 2020, 744 orchards were infected compared with 43 orchards in 2015 in Korea. When are insufficient. In Korea, all host plants in infected orchards are buried deeply with lime to eradicate the E. amylovora outbreak within a few days. Apple trees with infected trunks and branches and twigs with infected leaves and infected blooms were collected from an apple orchard in Chungju, Chungbuk province, where fire blight occurred in 2020. We used these samples to investigate the population density and internal distribution of E. amylovora on infected branches and twigs during early season infections. Infected branches and twigs were cut at 10 cm intervals from the infected site, and E. amylovora was isolated from tissue lysates to measure population density (colony-forming unit [CFU]·mL^-1). The polymerase chain reaction was performed on genomic DNA using E. amylovora specific primers. Real-time polymerase chain reaction (PCR) was performed to detect E. amylovora in asymptomatic tissue. The objective of these assays was to collect data relevant to the removal of branches from infected trees during early season infection. In infected branches, high densities of greater than 10⁶ CFU·mL^-1 E. amylovora were detected within 20 cm of the infected sites. Low densities ranging from 10² to 10⁶ CFU·mL^-1 E. amylovora were found in asymptomatic tissues at distances of 40 - 75 cm from an infection site.

• Animal Bioscience
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• v.35 no.4
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• pp.556-566
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• 2022

Objective: This study aimed to determine the appropriate supplementation level of lactic acid bacteria (LAB; Lactobacillus plantarum and Bacillus clausii), yeast (Saccharomyces cariocanus and Wickerhamomyces anomalus) for degrading free gossypol and glucosinolate in the fermented total mixed ration (TMR) containing cottonseed meal (CSM) or rapeseed meal (RSM), to improve the utilization efficiency of these protein sources. Methods: For LAB, L. plantarum or B. clausii was inoculated at 1.0×10⁸, 1.0×10⁹, 1.0×10¹⁰, and 1.0×10¹¹ colony-forming unit (CFU)/kg dry matter (DM), respectively. For yeast, S. cariocanus or W. anomalus was inoculated at 5×10⁶, 5×10⁷, 5×10⁸, and 5×10⁹ CFU/kg DM, respectively. The TMR had 50% moisture and was incubated at 30℃ for 48 h. After fermentation, the chemical compositions, and the contents of free gossypol and glucosinolate were determined. Results: The results showed that the concentration of free gossypol content was reduced (p<0.05), while that of the crude protein content was increased (p<0.05) in the TMR containing CSM inoculated by B. clausii (1×10⁹ CFU/kg DM) or S. cariocanus (5×10⁹ CFU/kg DM). Similarly, the content of glucosinolate was lowered (p<0.05) and the crude protein content was increased (p<0.05) in TMR containing RSM inoculated with B. clausii (1×10¹⁰ CFU/kg DM) or S. cariocanus (5×10⁹ CFU/g DM). Conclusion: This study confirmed that inclusion of B. clausii with 1.0×10⁹ or 1.0×10¹⁰ CFU/kg DM, or S. cariocanus (5×10⁹ CFU/kg DM) to TMR containing CSM/RSM improved the nutritional value and decreased the contents of anti-nutritional factors.

• Journal of Oral Medicine and Pain
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• v.32 no.4
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• pp.375-381
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• 2007

Occlusal stabilization appliance is one of the most common treatment option for management of temporomandibular disorders. It acts in oral cavity for several hours per day, and usually it will take at least 6 months to 2 years of total wearing periods to take a treatment goal. In the oral cavity, occlusal stabilization appliance, unintentional manner, is able to acts as a reservoir of bacteria and protect bacteria from saliva and oxygen. This condition is so favorable to many bacteria such as S. mutans and other anaerobes, usually have been reported as causative factors of dental caries, periodontal disease and oral malodor. In this study, we investigated anaerobic bacteria and S. mutans count before and after occlusal stabilization appliance use to evaluate the possible role of occlusal stabilization appliance as protector of these bacteria. Four men(average 27.5 years) wore maxillary occlusal stabilization appliance at each night(average 9 hours) for 5 days. we swabbed saliva-plaque mixed sample at 3 different site(maxillary left 2nd molar, maxillary left central incisor, mandibular left 2nd molar) before and after occlusal stabilization appliance use. Each samples were plated in (1) anaerobic blood agar medium, (2) selective S. mutans medium(MS-MUTV) and incubated in anaerobic chamber($CO^2$ 10%, $37^{\circ}C$) for 72 hours. Each bacterial colony forming unit(CFU) were counted with naked eyes. From obtained data, we can conclude as follows: 1. There was some changes about anaerobic bacteria and S. mutans count in oral cavity after occlusal stabilization appliance use. 2. The number of anaerobic bacteria was significantly increased at maxillary 2nd molar(P=0.003), maxillary central incisor(P=0.020) after occlusal stabilization appliance use compared with before. 3. Occlusal stabilization appliance use itself had indirect effect to increase the number of anaerobic bacteria at other uncovered opponent tooth site. 4. The number of S. mutans was significantly increased at maxillary 2nd molar(P=0.043), maxillary central incisor (P=0.049) after occlusal stabilization appliance use compared with before. 5. Occlusal stabilization appliance use itself had not any effect on the number of S. mutans at other uncovered opponent tooth site.

• The Korean Journal of Food And Nutrition
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• v.1 no.1
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• pp.33-40
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• 1988

A Study was conducted to investigate the effect of feeding Lactobacillus casei YS on the growing performance and gastrointestinal flora of the suckling piglets, which were delivered from 2 heads of three-way crossbred(Landrace$\times$Large White$\times$Duroc) pigs, for 4 weeks. The results from the present study was summarized as follows. Average body weight gains of feeding group was slightly better than that of control group and diarrhea was prevented by successive 7 days feeding. Population levels of lactic acid bacteria were maintained about 107 colony forming unit(cfu) per gram of the contents in both feeding and control group at upper parts of small intestine. In this part, coliform count was greatly reduced in (ceding group but not in control group. pH values of the intestinal contents were gradually decreased especially at the upper part of alimentary track of feeding group. Among lactic acid bacteria, L. salivarius, L. cases and L. fermentum were found most predominant strains in feeding group, Wheareas L. salivarius, L. acidophilus and L. cunts in control group. In the other hand, Escherichia coli recovered from scouring pigs were resistant to the drug such as streptomycin, ampicillin and sensitive to gentamycin and neomycin in vitro test.

• The Journal of Advanced Prosthodontics
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• v.3 no.1
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• pp.20-24
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• 2011

PURPOSE. The aim of this study was to identify in vitro antimicrobial activity of the tissue conditioner containing silver nanoparticles on microbial strains, Staphylococcus aureus, Streptococcus mutans and Candida albicans. MATERIALS AND METHODS. Experimental disc samples ($20.0{\times}3.0$ mm) of tissue conditioner (GC Soft-Liner, GC cooperation, Tokyo, Japan) containing 0.1 - 3.0% silver nanoparticles (0%: control) were fabricated. Samples were placed on separate culture plate dish and microbial suspensions (100 ${\mu}L$) of tested strains were inoculated then incubated at $37^{\circ}C$. Microbial growth was verified at 24 hrs and 72 hrs and the antimicrobial effects of samples were evaluated as a percentage of viable cells in withdrawn suspension (100 ${\mu}L$). Data were recorded as the mean of three colony forming unit (CFU) numerations and the borderline of the antimicrobial effect was determined at 0.1% viable cells. RESULTS. A 0.1% silver nanoparticles combined to tissue conditioner displayed minimal bactericidal effect against Staphylococcus aureus and Streptococcus mutans strains, a 0.5% for fungal strain. Control group did not show any microbial inhibitory effect and there were no statistical difference between 24 hrs and extended 72 hrs incubation time (P > .05). CONCLUSION. Within the limitation of this in vitro study, the results suggest that the tissue conditioner containing silver nanoparticles could be an antimicrobial dental material in denture plaque control. Further mechanical stability and toxicity studies are still required.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.5
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• pp.383-388
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• 2004

The conversion of a cellulose-producing cell ($Cel^+$) from Gluconacetobacter hansenii PJK (KCTC 10505 BP) to a non-cellulose-producing cell ($Cel^-$) was investigated by measuring the colony forming unit (CFU). This was achieved in a shaking flask with three slanted baffles, which exerted a strong shear stress. The addition of organic acid, such as glutamic acid and acetic acid, induced the conversion of microbial cells from a wild type to $Cel^-$ mutants in a flask culture. The supplementation of $1\%$ ethanol to the medium containing an organic acid depressed the con-version of the microbial cells to $Cel^-$ mutants in a conventional flask without slanted baffles. The addition of ethanol to the medium containing an organic acid; however, accelerated the conversion of microbial cells in the flask with slanted baffles. The $Cel^+$ cells from the agitated culture were not easily converted into $Cel^-$ mutants on the additions of organic acid and ethanol to a flask without Slanted baffles, but some portion of the $Cel^+$ cells were converted to $Cel^-$ mutants in a flask with slanted baffles. The conversion ratio of $Cel^+$ cells to $Cel^-$ mutants was strongly re-lated to the production of bacterial cellulose independently from the cell growth.