• Korean Journal of Microbiology
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• v.28 no.3
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• pp.199-203
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• 1990

To study distribution of bacterial flora and their biochemical characteristics in the Antarctic soilecosystem, these experiments were performed during the austral summer(Feb., 1989) on the King George Island, Antarctica. The numbers of heterotrophic bacterial colonies and extracellular enzyme actibities were estimated from the Antarctic terrestrial soils which were sampled from 17 different locations near Sejong station (Korea) and Teniente Jubany station (Argentina) on the King George Island. The numbers of heterotrophic bacterial colonies were extremely variable with sampling sites and incubation temperatures. Arithmetric average numbers were $2.5\times 10^{4}$, $2.7\times 10^{7}$ , $6.9\times 10^{5}$ CFU/$cm^{3}$ soil at the incubation temperature of $37^{\circ}C$, $25^{\circ}C$ and $4^{\circ}C$, respectively. The activities of extracellular $\alpha$-glucosidase, $\beta$-glucosidase and N-acetyl-$\beta$-glucosaminidase were shown as similar mean percentage in the colonies obtained at different temperatures. Mean value of protease activities, however, was remarkably higher (92%) in the colonies grown at $4^{\circ}C$,.

• The Korean Journal of Food And Nutrition
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• v.20 no.4
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• pp.363-368
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• 2007

Traditional kochujang samples were collected from the folk village in Sunchang to find the major microbial composition and correlation between the taste and the microbial properties. Among the 29 samples, 17 samples showed Bacillus licheniformis as dominant strain with 11 samples Bacillus subtilis and 1 sample Staphylococcus pasteuri. Subdominant strain of 17 samples was Bacillus licheniformis with 12 samples Bacillus subtilis. Dominant strain numbers varied in rage of $6.60{\sim}8.38$ logCFU/g with subdominant strain number $5.90{\sim}7.86$ logCFU/g and total microbial number $6.64{\sim}8.56$ logCFU/g respectively. Bacterial type number varied in range of $6{\sim}18$ with the average 10.5 types. Fungi were found only in 2 samples and identified all to be Aspergillus oryzae. Yeasts were found in 25 samples. The dominant yeast strain of 23 samples was identified to be Zygosaccharomyces pseudorouxii and that of 2 samples Zygosaccharomyces rouxii. Yeast type variety showed that only single type was found in 15 samples, 2 types in 8 samples, 3 types in 1 sample and 4 types in 1 sample. Fungal number was 3.90 and 4.08 logCFU/g and yeast numbers varied in range of $3.90{\sim}6.43$ logCFU/g. The sensory scores of kochujang showed positive correlation with type numbers, but no significant correlation with the other microbial properties like total bacterial number, dominant bacterial number, subdominant bacterial number and dominant yeast number.

• Korean Journal of Microbiology
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• v.35 no.1
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• pp.35-40
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• 1999

Effects of different molecular size fractions (100,000 nMW-0.1 $\mu\textrm{m}$m, 10,000 nMW-100,000 nMW and 1,000 nMW-'L0,000 nMW) of dissolved organic matter on the bacterial numbers and $\beta$-glucosidase activities in Lake Soyang were investigated. Even though the concentrations and characteristics of each fractions were different, bacterial growth curves of each fractioii were Lypical and similar. Each growth curve had highest peak of $1.1{\times}10^{7}$ cells $ml^{-1}$. But, the $\beta$-lucosidase activitics of each fraction were quite different. In high molecular weight fraction (HMW: 100,000 nMW-0.1 $\mu\textrm{m}$m), Vmax of Pglucosidase activity ranged from 550 to 1,160 nmol $1^{-1}$.$hi^{-1}$, but in low molecular weight f~action (1,000 nMW-10,000 nMW), that ranged from 1 to 14 om01 1$^[-1}$${-1}$

• Journal of Korean Biological Nursing Science
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• v.17 no.2
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• pp.97-103
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• 2015

Purpose: The aim of the study was to identify effects of oral care protocol on bacterial floras of the oral cavity and oral health status of intubated patients in an intensive care unit. Methods: The participants were 60 intubated patients who were recruited from an intensive care unit of a university hospital from Dec. 28, 2010 to Mar. 25, 2011. The participants were randomly assigned into 3 groups of 20 patients according to the application time of oral care (1-minute oral care, 2-minute oral care, and 3-minute oral care groups). The numbers of bacterial flora colonies in the oral cavity was assessed before and after the oral care. Oral health status was assessed using a Korean version of the Oral Assessment Guide developed by Elier et al. originally. Results: The numbers of bacterial flora colonies were less after oral care than those before the care, but there was no significant differences among the 3 groups after the care. Oral health status was better after the oral care than it was before the care, but there was also no significant differences among the 3 groups. Conclusion: If well-trained nurses perform oral care for 1 minute using a chlorhexidine swab on intubated patients, the numbers of bacterial flora colonies will be reduced and healthy oral status will be maintained.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.5
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• pp.643-647
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• 2004

An in vitro experiment was carried out to investigate effects of solid associated (SAB) and liquid associated bacteria (LAB) and the type of incubation substrate on ruminal fermentation and gas production profiles. Bacterial fraction did not influence total numbers of bacteria. Gas production degradation parameters were significantly influenced by bacterial fraction and type of substrate (p<0.05). There was significant interaction between bacterial fraction and type of substrate in gas production (p<0.01). Total VFA concentration and acetic and propionic acid ratio were also influenced by bacterial fraction and type of substrate with little differences in individual VFA concentration.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.2
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• pp.200-207
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• 2007

In vitro rumen incubation studies were conducted to determine effects of initial pH on bacterial attachment and fiber digestion. Ruminal fluid pH was adjusted to 5.7, 6.2 and 6.7, and three major fibrolytic bacteria attached to rice straw in the mixed culture were quantified with real-time PCR. The numbers of attached and unattached Fibrobacter succinogenes, Ruminococcus flavefaciens and Ruminocococcus albus were lower (p<0.05) at initial pH of 5.7 without significant difference between those at higher initial pH. Lowering incubation media pH to 5.7 also increased bacterial numbers detached from substrate regardless of bacterial species. Dry matter digestibility, gas accumulation and total VFA production were pH-dependent. Unlike bacterial attachment, maintaining an initial pH of 6.7 increased digestion over initial pH of 6.2. After 48 h in vitro rumen fermentation, average increases in DM digestion, gas accumulation, and total VFA production at initial pH of 6.2 and 6.7 were 2.8 and 4.4, 2.0 and 3.0, and 1.2 and 1.6 times those at initial pH of 5.7, respectively. The lag time to reach above 2% DM digestibility at low initial pH was taken more times (8 h) than at high and middle initial pH (4 h). Current data clearly indicate that ruminal pH is one of the important determinants of fiber digestion, which is modulated via the effect on bacterial attachment to fiber substrates.

• Korean Journal of Microbiology
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• v.43 no.1
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• pp.40-46
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• 2007

For restoration of disturbed ecosystem in Lake Paro, artificial floating island (AFI) was installed. Even though the lake water was oligo-mesotrophic, the macrophytes, such as Iris ensata, Iris pseudoacorus, Phragmites communis were growing well in the rubberized coconut fiber media. For elucidating this process, total bacterial numbers, active bacterial numbers and exoenzymatic activities of ${\beta}-glucosidase$ and phosphatase of pore water of media and lake water were analyzed. The average of total bacterial numbers, active bacterial numbers and exoenzymatic activities of ${\beta}-glucosidase$ and phosphatase were $28.6{\times}10^{6}\;cells/ml,\;22.7{\times}10^{6}\;cells/ml,\;452.9nM/L/hr,\;and\;16381.9nM/L/hr$ which were 10, 15, 22 and 38 times higher than those of lake water, respectively. Moreover, the total phosphorus and total nitrogen concentration of media showed high values of 0.82 mg/L and 7.0 mg/L, respectively, while those of lake water 0.07 mg/L and 2.3 mg/L. This results suggest that the bacteria was playing an important role for restoration of disturbed ecosystem with newly created microbial ecosystem in media of artificial floating island.

• Applied Biological Chemistry
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• v.21 no.2
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• pp.81-83
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• 1978

The effect of bentazon(3-isopropyl-1H-2,1,3-benzothiadiazine-(4)-3H-one-2,2-dioxide) at 50, 200ppm on nitrification of 100ppm applied $NH_4-N$, and on the numbers of nitrite-oxidizing bacteria, and on total bacterial and fungal populations were studied in a soil for six weeks. The herbicide retarded nitrification with increasing its treatment, which was coincident with the decrease of nitrite-oxidinzing bacterial populations. Bentazon treatment in a soil caused the decrease of total bacterial populations and inversely the increase of fungal populations for 2 weeks.

• Korean Journal of Microbiology
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• v.43 no.1
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• pp.14-18
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• 2007

The bacterial community structures at 2 sponge species belonging to the genus Baikalospongia and Lubomirskia in Lake Baikal were analyzed with fluorescent in situ hybridization (FISH) method. The total bacterial numbers in the genus Baikalospongia ranged from $7.2{\times}10^{7}\;to\;4.2{\times}10^{8}\;cells/ml$, and those in Lubomirskia from $1.2{\times}10^{8}\;to\;1.6{\times}10^{8}\;cells/ml$, while those of lake water were from $2.3{\times}7.7{\times}10^{5}\;cells/ml$. Total bacterial numbers in the sponges were $10^{3}-10^{4}$ times higher than those of lake water. In the genera Baikalospongia and Lubomirskia, the proportions of other unidentified bacterial groups to the Bacteria were 42.0-60.3% and 40.7-51.9%, respectively. These proportions were similar to those in lake water (22.6-46.3%). These results suggest that bacterial compositions in Lake Baikal water and sponges are highly unique.

• Asian-Australasian Journal of Animal Sciences
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• v.4 no.4
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• pp.369-375
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• 1991

A series of in vitro incubation studies with washed rumen bacteria were conducted to determine the influence of incubation time and concentrations of peptides, alanine, ammonia nitrogen and carbohydrate on the rate of peptide disappearance and on bacterial growth. Disappearance rate of tri-alanine (ala3) under various conditions was between 30.6 and $58.2mg\;hr^-$ per gram bacterial dry matter. Ala3 was removed from the incubation medium in an almost linear fashion as incubation time and ala3 concentration was increased. Washed rumen bacteria utilized ala3 faster than di-l-alanine (ala2) at all concentrations. Adding 9mM carbohydrate significantly increased ala3 disappearance, but level of ammonia nitrogen had no influence on ala3 disappearance. The presence of alanine in the medium significantly lowered ala3 utilization by rumen bacteria. Bacterial dry matter and nitrogen growth yield were not influenced by alanine and peptides when incubation medium already contained a sufficient level of ammonia nitrogen. Increased ammonia nitrogen in the presence of ala3 did not stimulate bacterial growth. Carbohydrate significantly increased bacterial dry matter and nitrogen growth as expected. Results indicate that the rate of peptide utilization by rumen bacteria may be altered by type and concentration of peptides, and energy supply, and this may be mediated through changes in numbers and type of bacteria.