• Journal of Microbiology and Biotechnology
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• v.27 no.12
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• pp.2199-2210
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• 2017

Soil burial is the most widely used disposal method for infected pig carcasses, but composting has gained attention as an alternative disposal method because pig carcasses can be decomposed rapidly and safely by composting. To understand the pig carcass decomposition process in soil burial and by composting, pilot-scale test systems that simulated soil burial and composting were designed and constructed in the field. The envelope material samples were collected using special sampling devices without disturbance, and bacterial community dynamics were analyzed by high-throughput pyrosequencing for 340 days. Based on the odor gas intensity profiles, it was estimated that the active and advanced decay stages were reached earlier by composting than by soil burial. The dominant bacterial communities in the soil were aerobic and/or facultatively anaerobic gram-negative bacteria such as Pseudomonas, Gelidibacter, Mucilaginibacter, and Brevundimonas. However, the dominant bacteria in the composting system were anaerobic, thermophilic, endospore-forming, and/or halophilic gram-positive bacteria such as Pelotomaculum, Lentibacillus, Clostridium, and Caldicoprobacter. Different dominant bacteria played important roles in the decomposition of pig carcasses in the soil and compost. This study provides useful comparative date for the degradation of pig carcasses in the soil burial and composting systems.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.460-465
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• 2003

A bacterium, named as strain KL34, producing extracellular pectinase was isolated from soil. The mophological cheracteristics of the isolated bacterium were gram-negative, rod-shaped and endospore unformed. Production of pectinase of strain KL34 was induced only by polygalacturonic acid added to the culture media as a sole carbon source. Pectinase activity of KL34 reached a maximum value in the culture conditions of pH 8.5 at $25^{\circ}C$. Optimal medium for pectinase production was determined to the composition of 2% polygalacturonic acid, 0.25% yeast extract, 0.02% $K_2HPO_4$, 0.02% $CaCl_2$, and 0.05% KCl per liter. The pectinase activity in the culture supernatant reached the highest amount of 54 U/ml after 3 days cultivation in the optimal media.

• Journal of Microbiology and Biotechnology
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• v.17 no.6
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• pp.913-918
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• 2007

A Gram-positive, aerobic, rod-shaped, nonmotile, endospore-forming bacterium, designated Gsoil $349^T$, was isolated from soil of a ginseng field and characterized using a polyphasic approach. Comparative analysis of 16S rRNA gene sequences revealed that the strain Gsoil $349^T$ belongs to the family Paenibacillaceae, and the sequence showed closest similarity with Cohnella thermotolerans DSM $17683^T$ (94.1%) and Cohnella hongkongensis DSM $17642^T$ (93.6%). The strain showed less than 91.3% 16S rRNA gene sequence similarity with Paenibacillus species. In addition, the presence of MK-7 as the major menaquinone and $anteiso-C_{15:0},\;iso-C_{16:0},\;and\;C_{16:0}$ as major fatty acids suggested its affiliation to the genus Cohnella. The G+C content of the genomic DNA was 53.4 mol%. On the basis of its phenotypic characteristics and phylogenetic distinctiveness, strain Gsoil $349^T$ should be treated as a novel species within the genus Cohnella for which the name Cohnella panacarvi sp. nov. is proposed. The type strain is Gsoil $349^T\;(=KCTC\;13060^T=\;DSM\;18696^T)$.

• Journal of Microbiology and Biotechnology
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• v.19 no.12
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• pp.1590-1595
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• 2009

Alternative methods for controlling bacterial endospore contamination are desired in a range of industries and applications. Attention has recently turned to natural products, such as essential oils, which have sporicidal activity. In this study, a selection of essential oils was investigated to identify those with activity against Bacillus subtilis spores. Spores were exposed to 13 essential oils, and surviving spores were enumerated. Cardamom, tea tree, and juniper leaf oils were the most effective, reducing the number of viable spores by 3 logs at concentrations above 1%. Sporicidal activity was enhanced at high temperatures ($60^{\circ}C$) or longer exposure times (up to 1 week). Gas chromatography-mass spectrometry analysis identified the components of the active essential oils. However, none of the major oil components exhibited equivalent activity to the whole oils. The fact that oil components, either alone or in combination, did not show the same level of sporicidal activity as the complete oils suggested that minor components may be involved, or that these act synergistically with major components. Scanning electron microscopy was used to examine spores after exposure to essential oils and suggested that leakage of spore contents was the likely mode of sporicidal action. Our data have shown that essential oils exert sporicidal activity and may be useful in applications where bacterial spore reduction is desired.

• Korean Journal of Microbiology
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• v.52 no.4
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• pp.500-502
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• 2016

Several bacterial species have been reported to be surviving after the ionizing radiation treatment due to the presence of sophisticated enzymes systems and some endospores producing bacterial strains can also resist, due to the presence of thick spore coat. In this study, we report the complete genome sequence of a bacterium Paenibacillus swuensis $DY6^T$, isolated from an irradiated soil sample. The genome comprised of 5,012,599 bp with the G+C content of 49.93%, the genome included 4,463 protein coding genes and 133 RNA genes.

• Journal of Microbiology and Biotechnology
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• v.9 no.5
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• pp.646-649
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• 1999

A thermophilic bacterium producing D-stereospecific dipeptidase was isolated from Korean soil samples. The enzyme hydrolyzed the peptide bond between D-alanyl-D-alanine (D-Ala-D-Ala). The isolated bacterial strain was rod shaped, gram-positive, motile, and formed an endospore. Morphological and physiological characteristics suggested this microorganism a thermophilic Bacillus species, and was named as Bacillus sp. BCS-l. The production of D-stereospecific dipeptidase was growth-associated and optimal at $55^{\circ}C$. The enzyme was applied for the synthesis of D-amino acid-containing peptide, N-benzyloxycarbonyl-L-aspartyl-D-alanine benzyl ester (Z-L-Asp-D-AlaOBzl), as a model reaction. A thermodynamically controlled synthesis of Z-L-Asp-D-AlaOBzl was achieved in an organic solvent.

• Journal of Microbiology and Biotechnology
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• v.14 no.2
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• pp.312-316
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• 2004

Five strains, producing bacterial thermostable L-arabinose isomerase, were isolated from Korean soil samples obtained from compost under high temperature circumstances. Among these strains, the CBG-Al showed the highest L-arabinose isomerase activity at $60^\circ{C}$ and was selected as a D-tagatose producing strain from D-galactose. This strain was identified as Geobacillus thermodenitrificans based on the 16S rRNA analysis, and biological and biochemical characteristics. The isolated strain was aerobic, rod-shaped, Gram-positive, nonmotile, and an endospore-forming bacterium. No growth was detected in culture temperature below $40^\circ{C}$. The maximum growth temperature and maximum temperature of enzyme activity were $75^\circ{C}$ and $65^\circ{C}$, respectively. In metal ion effects, $Ca^{2+}$ was the most effective enzyme activator with the reaction rate by 150%. In a 5-1 jar fermentor with 3-1 MY medium, L-arabinose isomerase activity was growth-associated and pH decreased rapidly after the initial logarithmic phase.

• Journal of Applied Biological Chemistry
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• v.50 no.4
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• pp.202-210
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• 2007

A total of 45 bacterial strains were isolated from the traditional Korean soybean-fermented food, Chungkookjang. Among these strains, seven strains were selected and identified based on morphological, physiological, and biochemical characteristics, as well as phylogenetic analysis using 16S rDNA sequences. All strains were Gram-positive, aerobic, motile, oxidase-positive, rod-shaped, and endospore-forming bacteria, and produced extracellular enzymes such as amylase, cellulase, lipase, protease, and xylanase. The isolates were grown in the presence of 0-11% (w/v) NaCl. Growth was optimal at pH 6-9 and at temperatures of $30-45^{\circ}C$. According to VITEK automicrobic system tests and supplementary tests, the isolates were similar to several species of the genus Bacillus. The phylogenetic analysis of seven bacterial strains based on comparisons of 16S rDNA sequences, revealed that the strains were closely related to Bacillus species. The identification of strains that produced surfactin was also carried out, based on PCR screening of the sfp gene. Among the seven isolated strains, six yielded a surfactin-positive result with PCR.

• Plant Resources
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• v.2 no.2
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• pp.81-87
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• 1999

Sixteen isolates showing relatively strong antagonicity against the ginger rhizome rot pathogen, Pythium zingiberum, were selected among the 155 isolates from ginger rhizome surfaces and rhizospheres of ginger cultivation fields in Wanju, Chonbuk. The isolate, 'HB 26-5'showing the strongest antagonicity was finally selected by testing duration of inhibition effect and pathogenicity to ginger. The isolated antagonistic microorganism, 'HB 26-5' was rod shape, gram positive and formed endospore. The isolate produced acids utilizing glucose, arabinose, xylose and mannitol, and acetoin at VP test, and grew anaerobically. Temperature range for growth was from 10 to 4$0^{\circ}C$ . Reaction to catalase and gelatin, hydrolysis were positive, and casein hydrolysis and indol production were negative. Based on the mycological characters and the fatty acid composition, it was identified as Bacillus polymyxa. The pathogenicity test of isolated Bacillus polymyxa 'HB 26-5'on 22 crop cultivars resulted that only the lettuce was influenced in germination, and the others were not affected.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.6
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• pp.553-556
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• 2006

A cis-1,2-dichloroethylene (cis-DCE)-degrading anaerobic bacterium, Clostridium sp. strain KYT-1, was isolated from a sediment sample collected from a landfill site in Nanji-do, Seoul, Korea. The KYT-1 strain is a gram-positive, endospore-forming, motile, rod-shaped anaerobic bacterium, of approximately $2.5{\sim}3.0\;{\mu}m$ in length. The degradation of cis-DCE is closely related with the growth of the KYT-1 strain, and it was stopped when the growth of the KYT-1 strain became constant. Although the pathway of cis-DCE degradation by strain KYT-1 remains to be further elucidated, no accumulation of the harmful intermediate, vinyl chloride (VC), was observed during anaerobic cis-DCE degradation. Strain KYT-1 proved able to degrade a variety of volatile organic compounds, including VC, isomers of DCE (1,1-dichloroethylene, trans-1,2-dichloroethylene, and cis-DCE), trichloroethylene, tetrachloroethylene, 1,2-dichloroethane, 1,1,1-trichloroethane, and 1,1,2-trichloroethane. Strain KYT-1 degraded cis-DCE at a range of temperatures from $15\;to\;37^{\circ}C$, with an optimum at $30^{\circ}C$, and at a pH range of 5.5 to 8.5, with an optimum at 7.0.