• Journal of Microbiology
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• v.33 no.3
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• pp.215-221
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• 1995

S. coelicolor A3(2) cells were treated with various redox-cycling agents on nutrient agar plates and examined for their effect on the growth and differentiation. When treated with plumbagin, severe effect on cell viability was observed at concentrations above 250 $\mu$M. However, the surviving colonies differentiated normally. When treated with 100 $\mu$M paraquat, growth rate was decreased and morphological differentiation was inhibited, while the survival rate was maintained at about 100% even at 5 mM paraquat. Menadione or lawsone did not cause any visible changes at concentrations up to 1 mM. The effect of paraquat was also observed when it was added to nutrient agar plate before spore inoculation. Paraquat had also observed when it was added to nutrient agar plate before spore inoculation. Paraquat had no effect on colonies growing on R2YE agar plates. Among the components of R2YE medium selectively added to nutrient agar medium, CaCl$_2$ was found to have some protective function from the inhibitory effect of paraquat. As a first step to study the mechanism of the inhibitory effect of paraquat on differentiation, resistant mutants which sporulate well in the presence of paraquat were screened following UV mutagenesis. Three paraquat-resistant mutants were isolated with a frequency of 3 $\times$10${-5}$. Their mutation sites were determined by genetic crossings. All three mutations were mapped to a single locus near arg4 at about 1 o'clock on the genetic map of S. coelicolor A3(2).

• Food Science and Biotechnology
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• v.15 no.6
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• pp.866-870
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• 2006

The maintenance of physiological activity during dilution is very critical for the accurate enumeration of Vibrio spp. in marine samples. We investigated the effect of various diluents on the recovery of Vibrio parahaemolyticus using the direct plate counting and most probable number (MPN) methods. The effects of NaCl (0.85 and 3%) and pH (from 6.6 to 7.4) in diluents based on distilled water or phosphate buffered saline (PBS) were evaluated with three V. parahaemolyticus strains. PBS-3% NaCl (pH 6.6), as opposed to PBS, was the most effective diluent at maintaining viable cell numbers up to 2 log CFU/g during dilution for direct plate counting using on thiosulfate citrate bile salts sucrose (TCBS) selective agar, as well as minimizing the difference in cell numbers between TCBS and non-selective nutrient agar. It also increased counts of V parahaemolyticus inoculated into oysters relative to PBS (p<0.01), suggesting that PBS-3% NaCl (PH 6.6) can reduce the problem of underestimating V. parhaemolyticus counts using PBS alone.

• Journal of Pharmacopuncture
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• v.7 no.1 s.12
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• pp.37-51
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• 2004

Objective : Recently scolopendrid aqua-acupuncture has been a good effect on pain control but it has not been known about clinical safety. The purpose of this study was to investigate acute toxicity of scolopendrid aqua-acupuncture. Method : In order to prove the clinical safety of scolopendrid aqua-acupuncture, We have observed a bacteriological examination and clinical pathology test after scolopendrid aqua-acupuncture treatment. Balb/c mice were injected intravenous with Scolopendrid aquaacupuncture treatment for $LD_{50}$ and acute toxicity test. We analyzed physical reaction(side effect)and clinical pathology test before and after Scolopendrid aqua-acupuncture treatment of mice and 20 patients suffering from pain, who admitted department of Acupunture and Moxibustion, College of Oriental Medicine, Won-Kwang University Kwangju hospital. Results : In the Blood agar plate and Nutrient agar plate, a bacteriological examination did not show a bacillus. In acute $LD_{50}$ toxicity test, there was no mortality thus unable to attain the value. Examining the toxic response in the acute toxicity test, there was no sign of toxication. In acute toxic test, running biochemical serum test couldn't yield any differences between the control and experiment groups. In the 20 patients treated with Scolopendrid aqua-acupuncture, hematologic test did not show remarkable change. In the 20 patients treated with Scolopendrid aqua-acupuncture, Liver function test(AST, ALT, ALP) showed a slight decrease on the contrary, and abnormal rate showed a decrease of 5.0% compared with previous study. Reanl function test(BUN, Cr) and abnormal rate showed a decrease of 5.0% compared with previous study. In the 20 patients treated with Scolopendrid aqua-acupuncture, Electrolyte were normal range before and after treatment. In the Urine analysis of 20 patients, Leukocyte, Protein, Glucose, Keton, Bilirubin, U-bilinogen were not detected before and after Scolopendrid aqua-acupuncture treatment, and the rest almost made no difference.

• KSBB Journal
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• v.32 no.2
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• pp.133-139
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• 2017

Rheum palmatum has traditionally been used as a preventive agent and medication against fever and infection. The aim of this study was to isolate and characterize an antibacterial substance from R. palmatum that is effective against bacterial vaginosis. A methanol extract from R. palmatum showed antibacterial activity against Lactobacillus vaginalis KC TC 3515, Chryseobacterium gleum KCTC 2904, and Sphingomonas paucimobilis KCTC 2834, which cause bacterial vaginosis. After extraction and pH control of the methanol extract from R. palmatum, we found that acidic and alkaline extracts did not show antibacterial activity. A neutral extract (50 mg/mL) displayed an inhibitory zone of 18 mm on a nutrient agar plate with C. gleum KCTC 2904. Fractions No. 11 and 12 among 41 fractions obtained by silica gel column chromatography produced inhibitory zones of 10 mm on nutrient agar plates with C. gleum KCTC 2904. $R_f0.15$ and $R_f0.17$ spots produced by TLC of fraction No. 11 showed antibacterial activity against C. gleum KCTC 2904. Isolation and purification of the peak at a retention time (Rt) of 9.427 min was achieved by HPLC of $R_f0.29spots$. The peak at Rt 9.427 min showed antibacterial activity against C. gleum KCTC 2904.

• Journal of Life Science
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• v.10 no.1
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• pp.74-78
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• 2000

This study was investigated to evaluate the distribution of airborne microorganisms at underground shops in Seomyun and Nampodong, Pusan. The number of bacterial colonies on the nutrient agar plate plates were calculated by the open petri dish method for 30 minutes in indoor air of underground shops at every seasons in a year. There was no statistically significant difference between Seomyun and Nampodong in mean colony counts. Isolation rates of Gram positive rods was highest, and Gram positive cocci and Gram negative rods were followed. In Nampodong underground shops, Enterobacteriaceae strains was isolated. Mean colony counts according to seasons was higher at summer and autumn in Seomyun, and spring and winter in Nampodong. In near future, a study on the distribution of bacteria causing respiratory infection should be followed.

• The Journal of the Korean dental association
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• v.15 no.12
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• pp.963-968
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• 1977

1. The purpose of this study is to determine the antibacterial effect of the remedies commonly used in operative dentistry. 2. Experiment were performed against staphylococcus albus which were isolated from different root canals. 3. Isolated bacteria were inoculated on nutrient agar and disk which has been saturated antiseptics were placed on it, then this plate was incubated for 48 hours at 37℃. 4. Inhibition zone were measured around antiseptic disks. 5. The results of 45 cases of experiments showed as follows. Average diameter of inhibition zone around phenol disk was 2.99 mm, camphorated phenol, 0.74 mm, formocresol, 13.46mm, formocresol (Korea), 12.7 mm, eugenol, 4.74mm, thymol, 16.46 mm.

• Journal of Microbiology and Biotechnology
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• v.22 no.12
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• pp.1621-1628
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• 2012

The agar-degrading bacterium GNUM-1 was isolated from the brown algal species Sargassum serratifolium, which was obtained from the West Sea of Korea, by using the selective artificial seawater agar plate. The cells were Gram-negative, $0.5-0.6{\mu}m$ wide and $2.0-2.5{\mu}m$ long curved rods with a single polar flagellum, forming nonpigmented, circular, smooth colonies. Cells grew at $20^{\circ}C-37^{\circ}C$, between pH 5.0 and 9.0, and at 1-10% (w/v) NaCl. The DNA G+C content of the GNUM-1 strain was 45.5 mol%. The 16S rRNA sequence of the GNUM-1 was very similar to those of Alteromonas stellipolaris LMG 21861 (99.86% sequence homology) and Alteromonas addita $R10SW13^T$(99.64% sequence homology), which led us to assign it to the genus Alteromonas. It showed positive activities for agarase, amylase, gelatinase, alkaline phosphatase, esterase (C8), lipase (C14), leucine arylamidase, valine arylamidase, ${\alpha}$-chymotrypsin, acid phosphatase, naphthol-AS-BI-phosphohydrolase, ${\alpha}$-galactosidase, ${\beta}$-galactosidase, ${\beta}$-glucosidase, catalase, and urease. It can utilize citrate, malic acid, and trisodium citrate. The major fatty acids were summed feature 3 (21.5%, comprising $C_{16:1}{\omega}7c/iso-C_{15:0}$ 2-OH) and C16:0 (15.04%). On the basis of the variations in many biochemical characteristics, GNUM-1 was considered as unique and thus was named Alteromonas sp. GNUM-1. It produced the highest agarase activity in modified ASW medium containing 0.4% sucrose, but lower activity in rich media despite superior growth, implying that agarase production is tightly regulated and repressed in a rich nutrient condition. The 30 kDa protein with agarase activity was identified by zymography, and this report serves as the very first account of such a protein in the genus Alteromonas.

• Journal of Life Science
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• v.23 no.2
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• pp.259-266
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• 2013

To isolate the fibrinolytic enzyme, 268 strains from 21 samples were morphologically isolated from Cheonggukjang collected from Korea and Japan. Among the 268 strains, protease-producing bacteria were isolated in nutrient agar medium including 1% skimmed milk. As a result of this, 22 strains were isolated. Apiweb site was used to identify these strains based on their biochemical properties. In addition, 16S rRNA sequencing was performed to identify the strain. Most of the identified strains were Bacillus subtilis and B. amyloliquefaciens. Fibrinolytic enzyme activity was measured with the fibrin plate method. Five strains were finally selected: A2-14, A2-20, C1-05, C1-09, and F2-01. Of those five strains, the A2-20 strain, which is close to B. amyloliquefaciens, showed the strongest fibrinolytic activity. The fibrinolytic enzyme produced by the A2-20 strain was partially purified from culture supernatant by gel filtration and ion exchange chromatography. The optimal pH and temperature values of the partially purified enzyme were 7.0 and $35^{\circ}C$, respectively. Purified protein analysis was carried out with SDS-PAGE and zymography. A genetic analysis was also conducted by PCR based on the consensus sequence of fibrinolytic enzyme. Corresponding genes with a partial sequence of the A2-20 strain were identified.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.3
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• pp.367-376
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• 1997

Vibrio vulnificus is a gram-negative, halophilic, oxidase-positive, lactose-positive, motile, rod shaped bacterium that has been associated with primary septicemia and wound infection. Elucidating the growth and survival of V. vulnificus in ecological conditions is of great importance to develop sanitary measure against this microorganism. Thus we simulated the ecological conditions and evaluated the effect. About $10^5\;CFU/ml$ of V. vulnificus was inoculated to fresh water, brackish water $(1\%\;NaCl)$, sea water $(3\%\;NaCl)$, and bottom deposit solution. The same concentration of V. vulnificus was also inoculated to distilled water, $1\%\;NaCl$ solution and $3\%\;NaCl$ solution as controls. These were stored at 4, 15 and $25^{\circ}C$, respectively and were used to assess the effects of temperature and salinity on the survival of V. vulnificus. In fresh water V. vulnificus could not survive regardless of storage temperature. In case of brackish water and sea water survival time of V. vulnificus was the longest at $25^{\circ}C$, and the number of V. vulnificus was decreased most rapidly at $4^{\circ}C$. V. vulnificus survived longer in brackish water than in any other conditions. In bottom deposit solution containing brackish water, the survival time of V. vulnificus was longer and the rate of decline was slower than that in brackish water. These results indicate that both biological and physicochemical factors such as temperature and salinity could affect survival of V. vulnificus. V. vulnificus, damaged in normal fresh water, did not grow on TCBS agar of selective plating medium but grew on BHI agar plate; However, V. vulnificus was recovered by addition of salt and nutrient materials.

• Journal of Microbiology and Biotechnology
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• v.16 no.12
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• pp.1868-1873
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• 2006

A novel microorganism that could degrade high molecular weight gellan was screened and isolated from soil. On gellan plate, the microorganism grew well and completely liquefied the plate. The gellan-degrading microorganism was isolated by pure culture on glucose and nutrient agar medium afterwards. The 16S rDNA sequence analysis and biochemical tests using an API 50CHB/20E kit revealed that the strain belonged to Bacillus sp. The isolate, named as Bacillus sp. YJ-1, showed optimum gellan-degrading activity in 0.5% gellan medium at pH 7.5 and 37$^{\circ}C$. The activity was measured and evaluated by the thiobarbituric acid and thin-layer chromatography method. Mass spectrometry revealed that the major gellan.. depolymerized product was an unsaturated tetrasaccharide consisting of $\Delta$4,5-glucuronic acid-(1$\rightarrow$4 )-$\beta$-D-glucose-(1$\rightarrow$4)- $\alpha$-L-rhamnose-(1$\rightarrow$3)-$\beta$-D-glucose, which is a dehydrated repeating unit of gellan, thus the enzyme was identified as gellan lyase. When the gellan was present in the medium, the gellan-degrading activity was much higher than that in glucose-grown cells. These results indicate that in the presence of gellan, Bacillus sp. YJ-1 is able to metabolize the gellan by inducing gellan-degrading enzymes that can degrade gellan into small molecular weight oligosaccharides, and then the gellan. depolymerized products are taken up by the cells and utilized by intracellular enzymes.