• Journal of environmental and Sanitary engineering
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• v.1 no.1 s.1
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• pp.59-67
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• 1986

This sanitary survey was carried out to investigate the bacteriological contamination of cooking utensils and foods of moving tavern in eight sample sites of Seoul area. The results of survey were as follows: 1. The counts by means of total bacteria in cooking utensils and food samples by standard plate count method were as follow: $5.6\times10^5$ per gm in dishcloth, $3.1\times10^6$ per ml in dishwater. In food samples, $5.4\times10^5$ per gm in meat was higher than other samples. 2. The average counts total coliform and fecal coliform in samples by MPN method were as follow: $3.4\times10^4$ MPN per 100ml, and $1.3\times10^2$ MPN per 100ml in chopping board, $6.1\times10^4$MPN per gm and $1.0\times10^2$ MPN per gm in dishcloth, $1.8\times10^5$ MPN per 100ml and $6.1\times10^2$ MPN per 100ml in dishwater. In food samples, $3.1\times10^4$MPN per gm and $2.0\times10^2$ MPN per gm in meat was higher than other samples. 3. The counts by means of Pseudomonas in samples by MPN method were as follow: $2.8\times10^3$ MPN per 100ml in chopping board, $4.7\times10^3$ MPN per gm in dishcloth $5.6\times10^3$ MPN per 100ml in dishwater. In food samples, $2.4\times10^3$ MPN per gm in shellfish was higher than other samples. 4. Isolation cases of Food poisoning organisms from samples were as follow: Staphylococci was detected 9 cases $(17.6\%)$ in chopping board, 7 cases $(13.6\%)$ in dishcloth. In food samples, 9 cases $(25.7\%)$ in meat, 1 case $(4\%)$ in fish samples. Salmonella was detected 2 cases $(3.9\%)$ in dishwater, 1 case in meat samples.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.2
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• pp.205-212
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• 2008

This study aimed to investigate the biofilm formation, bacterial regrowth, and bacterial community structure in the granular-activated carbon (GAC) filter adsorbers (FAs) used in water treatment plants. In 2005 and 2006, raw water, settled water, GAC FA by depth, and filtered water were collected twice a year from water treatment plants (WTPs) B and S. The number of heterotrophic bacteria, including mesophilic and psychrophilic bacteria, in such collected waters was investigated along with the total number of coliforms therein. Heterotrophic bacteria were detected in most samples, mainly at the surface layers of the GAC FAs, and fewer such bacteria were found in the lower and bottom layers. An increase in the bacterial number, however, was observed in the samples from various depths of the GAC FAs in WTPs B and S compared with the surface layers. An increase in the bacterial number was also detected in the filtered water. This may indicate that there is a regrowth of the bacteria in the GAC FA. Considering, however, that heterotrophic bacteria were not found in the filtered water, it can be deduced that most bacteria are removed in the chlorination process. Coliforms were detected at the surface layer of the GAC FAs, but their regrowth was not observed. MicroLog systems were used to identify the bacteria community distribution. Eight genera and 14 species, including Pseudomonas spp., were detected in WTP B, and 8 genera and 9 species, including Aeromonas spp., in WTP S. Further studies are required to elucidate their role in the biofilms in water treatment processes.

• The Plant Pathology Journal
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• v.28 no.1
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• pp.68-74
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• 2012

Biocontrol microbes have mainly been screened among large collections of microorganisms $via.$ nutrient-rich $in$ $vitro$ assays to identify novel and effective isolates. However, thus far, isolates from only a few genera, mainly spore-forming bacilli, have been commercially developed. In order to isolate field-effective biocontrol microbes, we screened for more than 200 oligotrophic bacterial strains, isolated from rhizospheres of various soil samples in Korea, which induced systemic resistance against the soft-rot disease caused by $Pectobacterium$ $carotovorum$ SCC1; we subsequently conducted in $planta$ bioassay screening. Two oligotrophic bacterial strains were selected for induced systemic disease resistance against the $Tobacco$ $Mosaic$ $Virus$ and the gray mold disease caused by $Botrytis$ $cinerea$. The oligotrophic bacterial strains were identified as $Pseudomonas$ $manteilii$ B001 and $Bacillus$ $cereus$ C003 by biochemical analysis and the phylogenetic analysis of the 16S rRNA sequence. These bacterial strains did not exhibit any antifungal activities against plant pathogenic fungi but evidenced several other beneficial biocontrol traits, including phosphate solubilization and gelatin utilization. Collectively, our results indicate that the isolated oligotrophic bacterial strains possessing induced systemic disease resistance could provide useful tools as effective biopesticides and might be successfully used as cost-effective and preventive biocontrol agents in the field.

• Natural Product Sciences
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• v.23 no.3
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• pp.151-156
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• 2017

A phytochemical study of Alphonsea cylindrica King (unreported) has led to the isolation of six alkaloids. The compounds were identified as kinabaline (1; azafluorenone alkaloid), muniranine (2), O-methylmoschatoline (3; oxoaporphine alkaloid), lysicamine (4), atherospermidine (5) and N-methylouregidione (6; 4, 5-dioxoaporphine alkaloid). The structures of the isolated compounds were determined based on the spectroscopic techniques and by comparison with data reported in the literature. Alkaloid 2 was isolated as a new derivative of azafluorenone while alkaloids 1, 3 - 6 were isolated for the first time from Alphonsea species. In addition, alkaloid 3 and 4 showed inhibition zone against Staphylococcus aureus, Pseudomonas aeruginosa and Bacillus cereus in disc diffusion test. The minimum inhibition concentration (MIC) values of lysicamine (4) against S. aureus, B. cereus and P. aeruginosa were found to be smaller than O-methylmoschatoline (3). Therefore, the reported antibacterial activity showed the potential of this plant as natural antibacterial agent and supported the documented traditional use of Alphonsea sp. in the treatment of diarrhea and fever.

• Korean Journal of Food Science and Technology
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• v.43 no.4
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• pp.446-452
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• 2011

Total 480 lactic acid-producing bacteria were isolated from five kinds of kimchi, and their antibacterial activity was tested against Salmonella enterica serovar Typhimurium, Bacillus subtilis, and Pseudomonas aeruginosa using an agar diffusion assay. Among them, 340 isolates showed a halo on MRS agar against one or more indicator strains, which were identified using multiplex PCR, an API 50CHL kit, and a 16S rDNA sequence analysis. As a result, 169 Lactobacillus plantarum, 20 Lactobacillus fermentum, two Lactobacillus paracasei ssp. paracasei, two Lactobacillus sp., and 15 Pediococcus sp. were identified. This may be the first report on the isolation of antibacterial Lactobacillus fermentum from kimchi.

• Journal of Microbiology and Biotechnology
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• v.18 no.7
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• pp.1221-1226
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• 2008

The soft rot bacterium Pectobacterium wasabiae is an economically important pathogen of many crops. A new phytase gene, appA, was cloned from P. wasabiae by degenerate PCR and TAIL-PCR. The open reading frame of appA consisted of 1,302 bp encoding 433 amino acid residues, including 27 residues of a putative signal peptide. The mature protein had a molecular mass of 45 kDa and a theoretical pI of 5.5. The amino acid sequence contained the conserved active site residues RHGXRXP and HDTN of typical histidine acid phosphatases, and showed the highest identity of 48.5% to PhyM from Pseudomonas syringae. The gene fragment encoding the mature phytase was expressed in Escherichia coli BL21 (DE3), and the purified recombinant phytase had a specific activity of 1,072$\pm$47 U/mg for phytate substrate. The optimum pH and temperature for the purified phytase were pH 5.0 and 50$^{\circ}C$, respectively. The $K_m$ value was 0.17 mM, with a $V_{max}$ of 1,714 $\mu$mol/min/mg. This is the first report of the identification and isolation of phytase from Pectobacterium.

• Journal of Microbiology and Biotechnology
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• v.31 no.9
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• pp.1218-1230
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• 2021

Cold-adapted plant growth-promoting bacteria (PGPB) with multiple functions are an important resource for microbial fertilizers with low-temperature application. In this study, culturable cold-adapted PGPB strains with nitrogen fixation and phosphorus solubilization abilities were isolated. They were screened from root and rhizosphere of four dominant grass species in nondegraded alpine grasslands of the Qilian Mountains, China. Their other growth-promoting characteristics, including secretion of indole-3-acetic acid (IAA), production of siderophores and ACC deaminase, and antifungal activity, were further studied by qualitative and quantitative methods. In addition, whether the PGPB strains could still exert plant growth-promoting activity at 4℃ was verified. The results showed that 67 isolates could maintain one or more growth-promoting traits at 4℃, and these isolates were defined as cold-adapted PGPB. They were divided into 8 genera by 16S rRNA gene sequencing and phylogenetic analysis, of which Pseudomonas (64.2%) and Serratia (13.4%) were the common dominant genera, and a few specific genera varied among the plant species. A test-tube culture showed that inoculation of Elymus nutans seedlings with cold-adapted PGPB possessing different functional characteristics had a significant growth-promoting effect under controlled low-temperature conditions, including the development of the roots and aboveground parts. Pearson correlation analysis revealed that different growth-promoting characteristics made different contributions to the development of the roots and aboveground parts. These cold-adapted PGPB can be used as excellent strain resources suitable for the near-natural restoration of degraded alpine grasslands or agriculture stock production in cold areas.

• Microbiology and Biotechnology Letters
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• v.50 no.2
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• pp.255-269
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• 2022

Actinomycetes isolated from marine habitats represent a promising source of bioactive substances. Here, we report on the isolation, identification, productivity enhancement and application of the bioactive compounds of Streptomyces qinglanensis H4. Eighteen marine actinomycetes were isolated and tested for resistance to seven bacterial diseases. Using 16S rRNA sequencing analysis (GenBank accession number MW563772), the most powerful isolate was identified as S. qinglanensis. Although the strain produced active compound(s) against a number of Gram-negative and Gram-positive bacteria, it failed to inhibit pathogenic fungi. The obtained inhibition zones were 22.0 ± 1.5, 20.0 ± 1, 16.0 ± 1, 12.0 ± 1, 22.0 ± 1 and 24.0 ± 1 mm against Bacillus subtilis ATCC 6633, Escherichia coli ATCC 19404, Enterococcus faecalis ATCC 29212, Pseudomonas aeruginosa ATCC 9027, Candida albicans ATCC 10231 and Staphylococcus aureus ATCC6538, respectively. To maximize bioactive compound synthesis, the Plackett-Burman design was used. The productivity increased up to 0.93-fold, when S. qinglanensis was grown in optimized medium composed of: (g/l) starch 30; KNO₃ 0.5; K₂HPO₄ 0.25; MgSO₄ 0.25; FeSO₄·7H₂O, 0.01; sea water concentration (%) 100; pH 8.0, and an incubation period of 9 days. Moreover, the anticancer activity of S. qinglanensis was tested against two different cell lines: HepG2 and CACO. The inhibition activities were 42.96 and 57.14%, respectively. Our findings suggest that the marine S. qinglanensis strain, which grows well on tailored medium, might be a source of bioactive substances for healthcare companies.

• Journal of Life Science
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• v.26 no.11
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• pp.1259-1268
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• 2016

In this study, we investigated antimicrobial peptide from the acidified muscle extract of Mytilus coruscus, which mostly inhabits China, Japan, and Korea, to develop a natural product-derived antibiotics substitution in terms of its abuse and restriction. Antimicrobial peptide was purified by $C_{18}$ reversed-phase high-performance liquid chromatography and was detected as having a molecular mass of 6,701 Da by MALDI-TOF/MS. The N-terminal amino acid sequence of the purified peak was obtained from edman degradation, and 20 identified residues shown 100% identity with the N-terminus region of sperm-specific protein and protamine-like PL-II/PL-IV precursor of Mytilus californianus. We also identified 60 open-reading frame (ORF) encoding amino acids with 183 bp of purified peptide based on the obtained amino acid residues. The amino acid sequence of ORF showed 100% and the nucleotide sequence revealed 97.2% identity with the protamine-like PL-II/PL-IV precursor of Mytilus californianus. Synthesized antimicrobial peptide showed antimicrobial activity against gram-positive bacteria, including Bacillus cereus (minimal effective concentration [MEC], $20.8{\mu}g/ml$), Bacillus subtilis (MEC, $0.2{\mu}g/ml$), Streptococcus mutans (MEC, $0.2{\mu}g/ml$), gram-negative bacteria including Pseudomonas aeruginosa (MEC, $5.7{\mu}g/ml$), Escherichia coli (MEC, $2.6{\mu}g/ml$) and fungi, Candida albicans (MEC, $56.3{\mu}g/ml$). In addition, synthesized peptide showed stable activities under heat and salt conditions against gram-positive and gram-negative bacteria, but was inhibited by salt against only C. albicans. With these results, isolated peptide from M. coruscus could be an alternative agent to antibiotics for defending against pathogenic microorganisms, and helpful information to understand the innate immune system of marine invertebrates.

• Journal of Soil and Groundwater Environment
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• v.8 no.4
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• pp.27-35
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• 2003

The study site located in an industrial complex has a Precambrian age gneiss as a bedrock. The poorly-developed, disturbed soils in the study site have loamy-textured surface soil (1 to 2 m) and gravelly sand alluvium subsurface (2 to 6 m) on the top of weathered gneiss bedrock. The depth of the groundwater table was about 3.5 m below ground surface and increased toward down-gradient of the site. The hydraulic conductivity of transmitted zone (gravelly coarse sand) was in the range of 5.0${\times}$10$\^$-2/∼1.85${\times}$10$\^$-1/ cm/sec. The fine sand layer was in the range of 1.5${\times}$10$\^$-3/ to 7.6${\times}$10$\^$-3/ cm/sec. and the reclaimed upper soil layer was less than 10$\^$-4/ cm/sec. Toluene, ethylbenzene, and xylene (TEX) was the major contaminant in the soil and groundwater. The average depth of the soil contamination was about 1.5 m in the gravelly sand alluvium layer. At the depth interval 2.4∼4.8 m, the highest contamination in the soil is located approximately 50 to 70 m from the suspected source areas. The concentration of TEX in the groundwater was highest in the suspected source area and a lesser concentration in the center and southwest parts of the site. The TEX distribution in the groundwater is associated with their distribution in the soil. Microbial isolation showed that Pseudomonas flurescence, Burkholderia cepacia, and Acinetobactor lwoffi were the dominant aerobic bacteria in the contaminated soils. The analytical results of the groundwater indicated that the concentrations of dissolved oxygen (DO), nitrate, and sulfate in the contaminated area were significantly lower than their concentrations in the none-contaminated control area. The results also indicated that groundwater at the contaminated area is under anaerobic condition and sulfate reduction is the predominant terminal electron accepting process. The total attenuation rate was 0.0017 day$\^$-1/ and the estimated first-order degradation rate constant (λ) was 0.0008 day$\^$-1/.