• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.2
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• pp.105-111
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• 2002

The biological removal of 2,4,6-trinitrotoluene (TNT) was studied in a bench-scale bioreactor using a bacterial culture of strain OK-5 originally Isolated from soil samples contaminated with TNT. The TNT was completely removed within 4 days of incubation in a 2.5 L bench-scale bioreactor containing a newly developed medium. The TNT was catabolized in the presence of different supplemented carbons. Only minimal growth was observed in the killed controls and cultures that only received TNT during the incubation period. This catabolism was affected by the concentration ratio of the substrate to the biomass. The addition of various nitrogen sources produced a delayed effect for the TNT degradation. Tween 80 enhanced the degradation of TNT under these conditions. Two metabolic intermediates were detected and identified as 2-amino-4, 6-dinitrotoluene and 4-amino-2, 6-dinitrotoluene based on HPLC and GC-MS analyses, respectively. Strain OK-5 was characterized using the BIOLOG system and fatty acid profile produced by a microbial identification system equipped with a Hewlett Packard HP 5890 II gas chromatograph. As such, the bacterium was identified as a Stenotrophomonas species and designated as Stenotrophomonas sp. OK-5.

• Journal of Microbiology and Biotechnology
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• v.24 no.7
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• pp.936-942
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• 2014

Using racemic (R,S)-2-(4-chlorophenyl)-3-methylbutyramide, an intermediate for the chiral pyrethroid insecticide Esfenvalerate, as a sole nitrogen source in a minimal medium, several strains with high enatioselectivity (${\geq}98%$) were isolated by enrichment techniques. One of the strains, LG 31-3, was identified as Burkholderia multivorans, based on physiological and morphological tests by a standardized Biolog station for carbon source utilization. A novel amidase was purified from B. mutivorans LG 31-3 and characterized. The enzyme exhibited (S)-selective amidase activity on racemic (R,S)-2-(4-chlorophenyl)-3-methylbutyramide. Addition of the racemic amide induced the production of the enantioselective amidase. The molecular mass of the amidase on SDS-PAGE analysis was shown to be 50 kDa. The purified amidase was subjected to proteolytic digestion with a modified trypsin. The N-terminal and internal amino acid sequences of the purified amidase showed a high sequence homology with those deduced from a gene named YP_366732.1 encoding indole acetimide hydrolase from Burkholderia sp. 383.

• The Plant Pathology Journal
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• v.34 no.1
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• pp.1-10
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• 2018

A previously unreported bacterial disease on chili pepper (Capsicum annuum L.) seedlings affecting as many as 4% of seedlings was observed in greenhouses in Chihuahua, Mexico (Delicias and Meoqui counties). Initial lesions appeared as irregular small spots on leaves and brown necrosis at margins tips were observed. Later, the spots became necrotic with a chlorotic halo. Advanced disease was associated with defoliation. A Gram negative, rod-shaped bacterium was isolated from diseased chili pepper seedlings. Three inoculation methods revealed that isolated strains produce foliage symptoms, similar to those observed in naturally infected seedlings. Pathogenic strains that caused symptoms in inoculated seedlings were re-isolated and identified to fulfill koch's postulate. Polyphasic approaches for identification including biochemical assays (API 20E and 50CH), carbon source utilization profiling (Biolog) and 16S rDNA, hsp60 and rpoB sequence analysis were done. Enterobacter cloacae was identified as the causal agent of this outbreak on chili pepper seedlings.

• Journal of Life Science
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• v.18 no.3
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• pp.369-373
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• 2008

Staphylococcus intermedius (S. intermedius) has been rarely isolated from horse. In this study, we investigated the antimicrobial susceptibility patterns of S. intermedius isolated from skin lesions of Thoroughbred horse in Daegu Equestrian Association. The skin lesions were showed with dehairing and slight purulent inflammation. Bacteria were isolated from skin lesions and identified as S. intermedius by biochemical tests and MicroLog (BIOLOG, California, USA). Antimicrobial susceptibility test of S. intemedius isolates was performed with 33 antimicrobial agents (BBL, Maryland, USA) by using the agar disk diffusion method. It showed a high sensibility in the amikacin, amoxycillin/clavuramic acid, ampicillin, cefoxitin, cephalothin, chloramphenicol, ciprofloxacin, enrofloxacin, florfenicol, kanamycin, neomycin, nitrofurantoin, norfloxacin, ofloxacin, oxacillin, penicillin G, tetracycline and vancomycin. The horse was treated with penicillin, and cured completely after two weeks. The present results showed valuable information for treatment and prevention of skin disease in horse.

• Journal of Microbiology and Biotechnology
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• v.23 no.9
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• pp.1279-1286
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• 2013

Particle size and metal species are important to both soil microbial toxicity and phytotoxicity in the soil ecosystem. The effects of CuO and ZnO nanoparticles (NPs) and microparticles (MPs) on soil microbial toxicity, phytotoxicity, and bioaccumulation in two crops (Cucumis sativus and Zea mays) were estimated in a soil microcosm. In the microcosm system, soil was artificially contaminated with 1,000 mg/kg CuO and ZnO NPs and MPs. After 15 days, we compared the microbial toxicity and phytotoxicity by particle size. In addition, C. sativus and Z. mays were cultivated in soils treated with CuO NPs and ZnO NPs, after which the treatment effects on bioaccumulation were evaluated. NPs were more toxic than MPs to microbes and plants in the soil ecosystem. We found that the soil enzyme activity and plant biomass were inhibited to the greatest extent by CuO NPs. However, in a Biolog test, substrate utilization patterns were more dependent upon metal type than particle size. Another finding indicated that the metal NP uptake amounts of plants depend on the plant species. In the comparison between C. sativus and Z. mays, the accumulation of Cu and Zn by C. sativus was noticeably higher. These findings show that metal oxide NPs may negatively impact soil bacteria and plants. In addition, the accumulation patterns of NPs depend on the plant species.

• Food Science and Biotechnology
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• v.15 no.2
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• pp.214-219
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• 2006

A bacterial strain, initially identified as B1-3, was isolated from cheonggukjang, a traditional Korean dish made from fermented soybeans. Using the Biolog system and 16S rRNA sequence analysis, we identified B1-3 as Bacillus mojavensis. We manufactured a quickly fermented soybean (QFS) food product using the B. mojavensis, and guided by their 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging ability. We isolated substances with antioxidative activity from it. Using mass spectrometry (MS) and nuclear magnetic resonance (NMR) techniques, we isolated 4 compounds from the ethyl acetate (EtOAc)-soluble neutral fraction of methyl alcohol (MeOH) extracts of the QFS food product (genistein, daidzein, 3R,4R-3-methyl-3,4-dihydroxy-2-pentanone, and 3S,4R-3-methyl-3,4-dihydroxy-2-pentanone) and 3 compounds from its acidic fraction (4-hydroxyphenylacetic acid, genistin, and daidzein). Two compounds from the neutral fraction (3R,4R-3-methyl-3,4-dihydroxy-2-pentanone and 3S,4R-3-methyl-3,4-dihydroxy-2-pentanone) were not detected in nonfermented soybeans (NFS) or in the filtrate of the LB broth used to culture B. mojavensis. However, they were detected in the filtrate of the same broth when it contained 2% glucose. These results suggest that these 2 compounds were derived from glucose (or other saccharides) in the soybean during fermentation. One compound that was found in the acidic fraction (4-hydroxyphenylacetic acid) was readily detected in NFS, but not in the culture broth. This suggests that 4-hydroxyphenylacetic acid was derived from NFS. We concluded that the antioxidative activity of cheonggukjang is a result of the interactions between soybean components and the microorganisms used in the fermentation of cheonggukjang.

• The Plant Pathology Journal
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• v.22 no.2
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• pp.119-124
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• 2006

Kudzu vine(Pueraria montana var. lobata) is an invasive climbing woody vine that envelops trees and shrubs, pressing physically and shutting out sunlight, which needs to be controlled. Kudzu vine pathogens were surveyed as a way to seek its biocontrol agents in 2002. Occurrence of a bacterial halo blight disease of kudzu vine was observed at several localities in Korea including Euiwang and Suwon in Gyeonggi Province, Daejon, and Gochang and Buan in Jeonbuk Province. Symptoms of brown to black spots with a surrounding yellowish halo appeared from June and lasted till the rainy season without much expansion, but accompanying often leaf blight and defoliation. Isolated bacteria were identified as Pseudomonas syringae pv. phaseolicola based on physiological and cultural characteristics, Biolog, fatty acid and 16S rDNA sequencing analyses. In artificial inoculation test, these bacteria produced the same halo spot symptoms on kudzu vine and bean plants. They also induced hypersensitive responses (HR) on tobacco, tomato, and chili pepper leaves. This is the first report of a bacterial disease of kudzu vine in Korea, and the bacterial pathogen can be used as a biocontrol agent against the pest plant.

• KSBB Journal
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• v.30 no.5
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• pp.245-252
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• 2015

The aim of this study was to investigate the efficacy of enhanced physiological activities in cultures isolated from Korean fermented watery Kimchi, Dongchimi, of single lactic acid bacteria (LAB), and when these three are mixed LAB as probiotics. Using the BIOLOG system and 16S rRNA sequencing, the isolates were characterized, and identified and assigned to Leuconostoc mesenteroides DK-3, Leuconostoc dextranicum DK-6, and Lactobacillus curvatus DK-13, respectively. Growth rate and pH changes, production of organic acids as metabolites, and physiological activities of the single and mixed LAB cultures, were monitored and compared. In mixed LAB cultures after 72 h of incubation, the maximum concentrations of lactic acid and acetic acid were approximately 340.5 mM and 191.9 mM, respectively, and pH changed from 7.00 to 3.62. Mixed LAB cultures were able to eliminate 96.3% of nitrite. Activities of antioxidant and ${\beta}$-galactosidase were 60.3% and 16.8 units/mg, respectively. Significant antibacterial activity of the concentrated supernatants was demonstrated against several food-poisoning bacteria. Physiological activities obtained from the mixed LAB cultures have been shown to be considerably higher than those of single LAB cultures. In conclusion, these studies demonstrate that compared to the single cultures, all physiological activities in mixed LAB cultures are significantly enhanced.

• The Plant Pathology Journal
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• v.30 no.3
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• pp.288-298
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• 2014

We examined the efficacy of a bacterium for biocontrol of the root-knot nematode (RKN) Meloidogyne hapla in carrot (Daucus carota subsp. sativus) and tomato (Solanum lycopersicum). Among 542 bacterial isolates from various soils and plants, the highest nematode mortality was observed for treatments with isolate C1-7, which was identified as Bacillus cereus based on cultural and morphological characteristics, the Biolog program, and 16S rRNA sequencing analyses. The population density and the nematicidal activity of B. cereus C1-7 remained high until the end of culture in brain heart infusion broth, suggesting that it may have sustainable biocontrol potential. In pot experiments, the biocontrol efficacy of B. cereus C1-7 was high, showing complete inhibition of root gall or egg mass formation by RKN in carrot and tomato plants, and subsequently reducing RKN damage and suppressing nematode population growth, respectively. Light microscopy of RKN-infected carrot root tissues treated with C1-7 showed reduced formation of gall cells and fully developed giant cells, while extensive gall cells and fully mature giant cells with prominent cell wall ingrowths formed in the untreated control plants infected with RKNs. These histopathological characteristics may be the result of residual or systemic biocontrol activity of the bacterium, which may coincide with the biocontrol efficacies of nematodes in pots. These results suggest that B. cereus C1-7 can be used as a biocontrol agent for M. hapla.

• Journal of the Korean Society of Food Culture
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• v.15 no.4
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• pp.233-239
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• 2000

In order to optimize the quality of pine sprout tea, its chemical properties were analyzed and the yeasts associated with the quality of pine sprout tea during the storage were isolated and identified. In proximate composition moisture content was 20.13%, but other components except sugar were relatively low. Sugars such as glucose(30.15%), fructose(19.57%), and sucrose(9.27%) were major sugars which contained up to 76.73%. Total vitamin C and soluble tannin contents were 11.31 mg% and 68.31 mg%, respectively. Thirteen kinds of free amino acids were detected, but they were contained only in trace. In fatty acid composition 64.69% of fatty aids composed mainly of saturated fatty acids and major fatty acids were oleic acid, palmitic acid, and tricosaenoic acid. Among 8 mineral elements detected, calcium content was highest with 79.00 mg% and followed by potassium(45.16 mg%) and magnesium(8.93 mg%). The sweetness of pine sprout tea was gradually decreased from $70^{\circ}\;Brix\;to\;63^{\circ}\;Brix$ and 3.2% of ethanol at the initial concentration was increased to 6.0% during the storage of 40 days. The yeasts associated with the quality and alcohol formation of pine sprout tea during the storage were identified by Biolog MicrostationlTM system, as Zygosaccharomyces rouxii, Kluyveromyces lodderae, Kluyveromyces wickerhamii, and Pichia fluxuum.