• The Korean Journal of Food And Nutrition
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• v.10 no.1
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• pp.122-126
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• 1997

Bifidobacteria have been known as beneficial inhabitant of human intestine. Therefore, bifidobacteria began to be noticed as a starter in the manufacture of fermented dairy products. Perhaps the key for effective use of bifidobacteria in commercial dairy products is the maintenance of viability of bifidobacteria during large scale preparation of starter culture and distribution of products. So we tried to obtain the bifidobacteria having suitable characteristics for using as a starter in the manufacture of fermented dairy products. Among bifidobacteria isolated from Korean, E-4 strain showed the highest resistance to oxygen. To know whether the selected strain will be fit for manufacture of fermented dairy products, we also investigated resistance of the selected strain to HCI. The selected strain, E-4, was more resistant to environmental stresses such as oxygen, H2O2 and HCI than Bifidobacterium longum known as resistant strain to environmental stresses. According to carbohydrate fermentation patterns and morphological characteristics, E-4 strain was identified as B. bifidum. In conclusion, the selected strain, E-4, was thought to be fit for manufacture of fermented dairy products.

• Journal of Periodontal and Implant Science
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• v.32 no.2
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• pp.281-290
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• 2002

The purpose of this study is to develop species-specific DNA probe for detection and identification of Prevotella intermedia (P. intermedia) G8-9K-3. This study procedure includes (1) whole-genomic DNA extraction of P. intermedia G8-9K-3 (2) construction of the genomic DNA library, (3) screening of strain-specific DNA probe by reverse dot hybridization, (4) confirmation of strain-specific DNA probe by Southern blot hybridization, (5) determination of nucleotide sequences of strain-specific DNA probe. Twenty-eight recombinant plasmids containing Hind III-digested DNA fragments of P. intermedia G8-9K-3 were obtained. Reverse Dot Hybridization and Southern blot analysis data showed that one of them, Pig3, could be P. intermedia G8-9K-3-specific DNA probe. This datum indicates that this Pig3 DNA probe could be useful in detection and identification of the P. intermedia G8-9K-3 strain.

• Research in Plant Disease
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• v.21 no.3
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• pp.222-226
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• 2015

The chitinase-producing bacterial strain C-1 is one of the key chitinase-producing biocontrol agents used for effective bioformulations for biological control. These bioformulations are mixed cultures of various chitinolytic bacteria. However, the precise identification, biocontrol activity, and the underlying mechanisms of the strain C-1 have not been investigated so far. Therefore, we evaluated in planta biocontrol efficacies of C-1 and determined the draft genome sequence of the strain in this study. The bacterial C-1 strain was identified as a novel Serratia sp. by a phylogenic analysis of its 16S rRNA sequence. The Serratia sp. C-1 bacterial cultures showed strong in planta biocontrol efficacies against some major phytopathogenic fungal diseases. The draft genome sequence of Serratia sp. C-1 indicated that the C-1 strain is a novel strain harboring a subset of genes that may be involved in its biocontrol activities.

• The Journal of the Korean dental association
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• v.9 no.12
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• pp.807-811
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• 1971

This report was concerned with the isolation and identification of bacterial flora in the human dental plaque and the dextransucrase activity of isolated species. The results were obtained as follows: 1. The bacterial flora, isolated from the human dental plaque, was identified as 3 species of resembling streptococci, Streptococcus salivarius strain SD-1, Streptococcus bacilli, Lactobacillus brevis strain SD-3, Lactobacillus acidophilus strain SD-2 and SD-7, resembling Staphylococcus sp, and one species of resembling Leuconostoc mesenteroides strain SD-6. 2. The dextransucrase activites of resembling Streptococcus mitis strain SD-9 and Streptococcus salivarius strain SD-1 were exhibited the highest among the isolated species of human dental plaque.

• KSBB Journal
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• v.27 no.3
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• pp.151-156
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• 2012

Lactic acid is an important product arising from the anaerobic fermentation by lactic acid bacteria (LAB). It is used in the pharmaceutical, cosmetic, chemical, and food industries as well as for biodegradable polymer and green solvent production. The poly lactic acid (PLA) is an important material for bio-plastic manufacturing process. For PLA production by new LAB, we screened LAB isolates from shellfish. A total of 28 LAB were isolated from various shellfishes. They were all Gram positive, oxidase and catalase negative. Based on API 50CHL kit, 7 strains among the 28 isolates were identified as Lactobacillus plantarum, 6 strains as Lactobacillus delbrueckii, 5 strains as Leuconostoc mesenteroides, 3 strains as Lactobacillus brevis, 2 strains as Lactococcus lactis, 1 strain as Lactobacillus salivarius, 1 strain as Lactobacillus paracasei, 1 strain as Lactobacillus pentosus, 1 strain as Lactobacillus fermentum and 1 strain as Pediococcus pentosaceu. Also, we examined the amount of total lactic acid produced by these new strains by HPLC analysis with Chiralpak MA column. One strain E-3 from Mytilus edulis was indentified as Lactobacillus plantarum and found to produce 20.0 g/L of D-form lactic acid from 20 g/L of dextrose. Further studies are underway to increase the D-lactic acid production by E-3.

• Korean journal of food and cookery science
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• v.24 no.1
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• pp.11-15
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• 2008

In searching for yeast to be utilized as biocontrol agents, a single yeast strain was isolated from Camellia sinensis based on its morphological, cultural, physiological, and biochemical properties, as well as by molecular techniques. This single strain was pink to red in color and designated as strain JY-1. The effects of temperature, pH, NaCl concentration, and ethanol concentration on the growth of the JY-l strain were examined for the JY-1. Growth occurred at temperatures ranging from 20 to $35^{\circ}C$, and between pH 3.0 and 12.0, with optimal growth at $25-30^{\circ}C$ and pH 5.0. The yeast also grew in the presence of 0-2% (w/v) NaCl and 0-4% (v/v) EtOH. The isolate was further classified based on biochemical characteristics using the VITEK system. The biochemical data obtained using this system were similar to those of Rhodotorula glutinis/Rhodotorula mucilaginosa (exhibiting a 93% matching level). Molecular phylogenetic analysis based on l8S rDNA sequences indicated that the yeast represented a basidiomycetous species, and its highest degree of sequence similarity was with Rhodosporidium azoricum, strain JCM11251 (99%).

• Journal of Microbiology and Biotechnology
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• v.22 no.2
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• pp.256-263
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• 2012

A strain of bacterium producing antifungal antibiotic was isolated and identification of the strain was attempted. We could identify the bacterium as being a Bacillus sp., based on morphological observation, physiological characteristics, and 16S rDNA sequence analysis, thus leading us to designate the strain as Bacillus sp. AH-E-1. The strain showed potent antibiotic activity against phytopathogenic and human pathogenic fungi by inducing mycelial distortion and swelling and inhibiting spore germination. The antibiotic metabolite produced by the strain demonstrated excellent thermal and pH (2-11) stability, but was labile to autoclaving. From these results, we could find a broader antifungal activity of Bacillus genus. Isolation and characterization of the active agent produced by the strain are under progress.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.6
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• pp.818-824
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• 2003

This study was carried out to select Meju of a good quality through general composition analysis, organoleptic evaluation, and to conduct isolation, identification, and growth characteristics of main strain related to fermentation from selected Meju. Moisture and crude protein of Meju were 7.2∼28.8% and 32.7∼42.3%, respectively. The amino nitrogen contents of Kyongbuk and Chonbuk Mejus were 770.8 mg% and 239.9 mg%, respectively. And also, free amino acid and glutamic acid contents of Doenjangs made from Chonbuk and Kyongbuk Mejus were 4,169.6 mg% and 499.4 mg%, respectively. The result of sensory evaluation of Mejus collected from several regions showed Kyongbuk was the most suitable Meju in items of color, flavor, appearance and overall (p<0.05). The typical properties of B. lichenifomis NH20 strain isolated from Kyongbuk Meju showed gram positive, aerobic rod cell and motility. As major component among its cellular fatty acid composition, $C_{15:0}$ anteiso fatty acid, $C_{15:1}$ iso fatty acid, $C_{17:0}$ anteiso fatty acid, and $C_{17:0}$ iso fatty acid were 30.7, 28.9, 13.3 and 11.2%, respectively. It showed the same identification coefficient (0.653) compared to the standard strain. Therefore, it was identified to be B. licheniformis NH20 according to Bergey's Manual of Systematic Bacteriology and its fatty acid profiles. The optimum pH, temperature, salt content, and culture time of B. licheniformis NH20 were 7.0, 32$^{\circ}C$, 2%, and 9 hours, respectively.ctively.

• Structural Engineering and Mechanics
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• v.54 no.2
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• pp.199-219
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• 2015

This paper presents the non-destructive evaluation of a high-speed railway bridge using train-induced strain responses. Based on the train-track-bridge interaction analysis, the strain responses of a high-speed railway bridge under moving trains with different operation status could be calculated. The train induced strain responses could be divided into two parts: the force vibration stage and the free vibration stage. The strain-displacement relationship is analysed and used for deriving critical displacements from theoretical stain measurements at a forced vibration stage. The derived displacements would be suitable for the condition assessment of the bridge through design specifications defined indexes and would show certain limits to the practical application. Thus, the damage identification of high-speed railways, such as the stiffness degradation location, needs to be done by comparing the measured strain response under moving trains in different states because the vehicle types of high-speed railway are relatively clear and definite. The monitored strain responses at the free vibration stage, after trains pass through the bridge, would be used for identifying the strain modes. The relationship between and the degradation degree and the strain mode shapes shows certain rules for the widely used simply supported beam bridges. The numerical simulation proves simple and effective for the proposed method to locate and quantify the stiffness degradation.

• Journal of environmental and Sanitary engineering
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• v.9 no.1
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• pp.89-96
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• 1994

This report was investigate the biological characteristic of $\delta$-endotoxin of product by TH109 strain, one strain TH109 which has toxicity on Cockroach is isolate and identification. Generally the $\delta$-endotoxin of product by 3. thuringiensis strain was easily soluble in acid, alkaline and organic solvents but $\delta$-endotoxin of product by TH109 strain are insoluble in HCI, NaOH Thiol- reagent(25mM Dithiotheritol, 25mM Dithioeryritol, 25mM Nathioglycolate, 0.2M ESCN, 2% v/v $\beta$-mecaptethanol), organic solvents( acetone, $CCI_{4}$, ether, dioxin MeOH chloroforrh xylene ), Protease. Through this study of $\delta$-endotoxin produced by TH109 strain is insoluble in acid, alkaline, organic solvents and pretense etc. In the point of view, it is greater possibility that $\delta$-endotoxin will be transform into toxin by the reducible materials instead of the reaction of protease in the intestine.