• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.331.3-332
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• 2002

A novel penicillin G acylase (PGA)-producing bacterial strain was isolated from soil by using the Serratia marcescens overlay technique. The isolated strain was identified as Leclercia adecarboxylata based on the analyses of the biochemical characteristics (API 20E). the cellular fatty acid profile. and the 16S rDNA sequences. The gene encoding the PGA (pac gene) was cloned into the pHSG399 vector and the recombinant E. coliHB101 clones harboring the pac gene were isolated on agar plates containing phenylacetyl-L -leucine and penicillin G. (omitted)

• 한국환경과학회지
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• 제19권11호
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• pp.1391-1396
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• 2010

Three biphenyl-degrading microorganisms were isolated from polluted soil samples in Sasang-gu, Busan. Among them, isolate DS-94 showing the strong degrading activity was selected. The morphological, physiological, and biochemical characteristics of DS-94 were investigated by API 20NE and other tests. This bacterium was identified as the genus Pseudomonas by 16S rDNA sequencing and designated as Pseudomonas sp. DS-94. The optimum temperature and pH for the growth of Pseudomonas sp. DS-94 were $25^{\circ}C$ and pH 7.0, respectively. This isolate could utilize biphenyl as sole source of carbon and energy. Biphenyl-degrading efficiency of this isolate was measured by HPLC analysis. As a result of biological biphenyl-degradation at high biphenyl concentration (500 mg/L), biphenyl-removal efficiency by this isolate was 73.5% for 7 days.

• 한국환경과학회지
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• 제18권12호
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• pp.1331-1338
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• 2009

Marine dinoflagellate Alexandrium minutum producing paralytic shellfish toxins is responsible for paralytic shellfish poisoning (PSP). To investigate its temporal distributions in Chinhae Bay where PSP occurs annually, SYBR Green I based A. minutum-specific real-time PCR probe was developed on the LSU rDNA region. Assay specificity and sensitivity were tested against related species, and its specificity was further confirmed by sequencing of field-derived samples. Ten months field survey in 2008 (a total 100 surface water samples) by using the real-time PCR probe showed that A. minutum was detected at very low densities of 1-4 cells $L^{-1}$ in May and June being spring in Chinhae Bay, Korea.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.343-346
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• 2005

The isolated strain, SC2-1 was Gram-positive, catalase positive, facultatively anaerobic, oxidase negative, motile and small rods. The strain utilized sucrose, dextrose, fructose, mannitol and maltose as a sole carbon and energy source and sodium chloride required for the bacteria growth. The radical scavenging activity of the culture supernatants was determined by DPPH (1,1-diphenyl-2-picrylhydrazyl) method. This bacterium was identified based on cellular fatty acids analysis and 16S rDNA sequencing then named Exiguobacterium sp. SC2-1. The optimum culture conditions for production of antioxidant were $25^{\circ}C,$ pH 7.8 and NaCl concentration were 4%. The modified optimal medium compositions were maltose 2.5% (w/v), yeast extract 1.5% (w/v) and $KH_2PO_4$ 0.05% (w/v). Free radical scavenging activity of under optimal culture conditions were 93%.

• Asian-Australasian Journal of Animal Sciences
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• 제14권8호
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• pp.1170-1178
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• 2001

This study was conducted to isolate lactobacilli having characteristics to be used as health adjuncts with fermented milk products. Acid tolerant strains were selected in Lactobacilli MRS broth adjusted to pH 4.0 from human faeces. Bile tolerant strains were examined in Lactobacilli MRS broth in which 1.0% bile salt was added. Microhemagglutination tests using swine erythrocytes were performed to select lactobacilli having adherence properties to survive in the intestinal tract. By examination of these characteristics the strain Nam 27, which was isolated from adult faeces, was selected and identified as Lactobacillus salivarius subsp. salivarius based on carbohydrate fermentation and 16S rDNA sequencing.

• Mycobiology
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• 제33권4호
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• pp.210-214
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• 2005

More than 120 isolates of lactic acid bacteria obtained from Kimchi was screened for antifungal activity against Aspergillus fumigatus. Approximately 10% of the isolates showed inhibitory activity and only 4.16% (five isolates) exhibited strong activity against the indicator fungus A. fumigatus. The five isolates showed a wide rang of antifungal activity against A. flavus, Fusarium moniliforme, Penicillium commune, and Rhizopus oryzae. They were identified by 16S rDNA sequencing as Lactobacillus cruvatus, L. lactis subsp. lactis, L. casei, L. pentosus, and L. sakei. The effect of Lactobacillus on mycelial growth and fungal biomass as well as its ability to produce toxic compounds were determined. The results indicate that the three species, Lactobacillus casei, L. lactis subsp. lactis, and L. pentosus, are active against A. fumigatus.

• Journal of Microbiology and Biotechnology
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• 제14권1호
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• pp.48-55
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• 2004

Six strains of an obligate predatory bdellovibrio isolate that preys on Burkholderia glumae in rice paddy field water and rhizosphere soil, were identified and characterized. The numbers of Bdellovibrio cells varied from $3.2{\times}10^3$ to $9.2{\times}10^3$ plaque-forming unit/g after enrichment in cells of B. glumae. Prey range tests with six Bdellovibrio strains and 17 prey strains of rice-pathogenic, antibiosis-related, or nitrogen-fixing bacteria resulted in unique predation patterns in related prey cells. Strain BG282 had the widest prey range on 7 plant pathogenic bacteria among the 17 prey strains tested. However, no predation occurred with strains of Azospirillum brasilense, Paenibacillus polymyxa, Pseudomonas fluorescens, P. putida, and Serratia marcescens that are associated with antibiosis or nitrogen fixation in the rice ecosystem. Identification was confirmed by the presence of typical bdelloplast in the prey cells of B. glumae and by a PCR assay using B. bacteriovorus-specific primers. Furthermore, 16S rDNA sequencing of the six bdellovibrio strains showed a homology range of 97.2% to 99.2% to the type strain of B. bacteriovorus.

• Journal of Microbiology and Biotechnology
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• 제14권1호
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• pp.220-223
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• 2004

Club root caused by Plasmodiophora brassicae is found in crucifers. Among the over hundreds of Streptomyces isolated from soil in Korea. One strain showed prominent activity against P. brassicae. The strain was identified based on 16S rDNA sequencing and the morphology by a method of scanning electron microscopy. An active compound in the fermented broth obtained from the strain was separated. Even though the complete assignments of the compound remain for future work, the results regarding the isolation and characterization of the strain with a certain activity against P. brassicae are shown in this paper.

• Journal of Dairy Science and Biotechnology
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• 제36권2호
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• pp.125-131
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• 2018

The present study aimed to investigate the microbial diversity in Gouda cheese within the four months of ripening, via next-generation sequencing (NGS). Lactococcus (96.03%), and Leuconostoc (3.83%), used as starter cultures, constituted the majority of bacteria upon 454 pyrosequencing based on 16S rDNA sequences. However, no drastic differences were observed among other populations between the center and the surface portions of Gouda cheese during ripening. Although the proportion of subdominant species was <1%, slight differences in bacterial populations were observed in both the center and the surface portions. Taken together, our results suggest that environmental and processing variables of cheese manufacturing including pasteurization, starter, ripening conditions are important factors influencing the bacterial diversity in cheese and they can be used to alter nutrient profiles and metabolism and the flavor during ripening.

• Food Science and Biotechnology
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• 제15권1호
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• pp.86-90
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• 2006

Two lactic acid bacteria (LAB) with high ${\gamma}$-aminobutyric acid (GABA)-producing capacity were isolated from naturally aged cheese. Examination of the biochemical features using an API kit indicated that the two strains belonged to Lactobacillus. They were gram positive, rod-type bacteria, and fermented arabinose, melezitose, melibiose and xylose, but did not utilize cellobiose or trehalose. 16S rDNA sequencing analysis confirmed that they were Lactobacillus buchneri and Lactobacillus sp. They were accordingly named as Lactobacillus buchneri OPM-1 and Lactobacillus sp. OPM-2, and could produce GABA from MRS broth supplemented with 10 g/L of monosodium glutamate (MSG) at a productivity of 91.7 and 116.7 mg/L/hr, respectively. Cell extracts of L. buchneri OPM-1 and Lactobacillus sp. OPM-2 showed glutamate decarboxylase (GAD) activity, for which the optimum pH and temperature were 5.5 and $30^{\circ}C$, respectively.