• Korean Journal of Microbiology
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• v.46 no.3
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• pp.270-277
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• 2010

In order to manufacture Bacillus cereus-free fermented soybean products, an antimicrobial agentproducing isolate against B. cereus was obtained from 150 traditionally fermented soybean products. The morphological and biochemical tests and the phylogenetic relationship among 16S rRNA gene sequences indicated that the isolate named as the strain SCK 121057 was most closely related to Bacillus licheniformis. The B. licheniformis isolate began to produce the antimicrobial agent after 48 h of incubation. The agent was nonproteinaceous and insensitive to heat, long term storage and protease K. Electron microscopic observation indicated that the agent attacked the membrane of B. cereus, leaving the ghost cell. The isolate inhibited growth of B. subtilis, Lactobacillus brevis and various types of pathogenic strains including Escherichia coli, E. faecalis, Micrococcus luteus, Staphylococcus aureus, Aspergillus flavus, A. ochraceus, and A. parasiticus as well as B. cereus. After coinoculation of B. licheniformis SCK 121057 and B. cereus in the ratio (as the basis of CFU/g sample) of 10 to 1 on the surface of cooked soybeans, cell numbers of B. cereus had been dramatically reduced after 31 days of incubation compared to those of single inoculation of B. cereus.

• KSBB Journal
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• v.24 no.2
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• pp.149-155
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• 2009

19 strains, which could be identified as Lactobacillus sp. were isolated. The Cucurbita maxima has been known as a traditional healthy food and variable positive effects on the human body were already reported. In this study we tried to develop a production process for a healthy fermented drink with Cucurbita maxima and strains originated from Kimchi. Many kinds of lacctobacci species existed in the fermented food cannot survive in the acidic conditions in the stomach. So we tried to search and select a strain, which can arrive to the small intestine. A species of a Lactobacillus named as C332 was identifed as Lactobacillus plantarum and selected for the fermentation process. With the treatment with artificial gastric juice and artificial bile the survival rate of the cells could be calculated. The physiological characteristics at the variable conditions have been tested. After fermentation process the sensoric tests on the product with panels were tried. The most of the cells could survive in the acidic conditions and falcultive anaerobe. Especially some antibacterial effects aganinst E.coli were also found. With all kinds of the results from our research the fermented Cucurbita maxima drink can be a successful item in the market.

• Korean Journal of Clinical Laboratory Science
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• v.53 no.1
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• pp.49-59
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• 2021

This study investigated the use of real-time PCR melting curves for the diagnosis of blaKPC and blaNDM genes among the most frequently detected carbapenemase-producing Enterobacteriaceae in Korea. As a means of addressing the shortcomings of phenotype tests and conventional PCR. The modified Hodge test confirmed positivity in 25 of 35 strains, and carbapenemase inhibition testing confirmed positivity in 14 strains by meropenem+PBA or meropenem+EDTA. PCR analysis showed amplification products in 25 strains of Klebsiella pneumoniae carbapenemases (KPC), 10 of K. pneumoniae, 5 of E. coli, 5 of A. baumannii, 4 of P. aeruginosa, and 1 of P. putida. New Delhi metallo β-lactamase (NDM) identified amplification products in 8 strains, that is, 2 K. pneumoniae, 3 E. coli, 1 P. aeruginosa, 1 E. cloacae, and 1 P. retgeri strains. Real-time PCR melting curve analysis confirmed amplification in 25 strains of KPC and 8 strains of NDM, and these results were 100% consistent with PCR results. In conclusion, our findings suggest early diagnosis of carbapenem resistant Enterobacteriaceae by real-time PCR offers a potential means of antibacterial management that can prevent and control nosocomial infection spread.

• Journal of Life Science
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• v.31 no.12
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• pp.1100-1109
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• 2021

The halophyte Artemisia scoparia is an edible medicinal plant, with insecticidal, anti-inflammatory, anticholesterol, antipyretic, and antibacterial effects. The aim of this study was to assess the inhibitory effect of crude extract and solvent-partitioned fractions obtained from A. scoparia on MMP-2 and MMP-9 activity in phorbol-12-myristate-13-acetate (PMA)-stimulated human fibrosarcoma HT-1080 cells using four different activity tests: gelatin zymography, MMP enzyme-linked immunosorbent assay (ELISA), wound healing assay, reverse transcription-polymerase chain reaction (RT-PCR), and Western blot assay. A. scoparia samples were extracted twice with methylene chloride (MC) and twice with methanol (MeOH). After the MC and MeOH crude extracts were combined, the combined crude extracts showed a significant inhibitory effect against MMP-2 and MMP-9 enzymes. They were then fractionated into n-hexane, 85% (v/v) aqueous methanol (85% (v/v) aq.MeOH), n-butanol, and water according to solvent polarity. Among the four solvent-partitioned fractions, n-hexane and 85% (v/v) aq. MeOH fractions significantly inhibited MMP-2 and MMP-9 activity and cell mobility. In addition, the n-hexane and 85% (v/v) aq.MeOH fractions effectively inhibited MMP-2 and -9 activity in the gelatin zymography and MMP ELISA assay. In the wound healing assay, RT-PCR, and Western blot assay, all solvent-partitioned fractions, except the H₂O fraction, significantly suppressed cell migration, as well as the expression levels of MMP-2 and -9 mRNA and proteins.

• The Korean Journal of Pesticide Science
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• v.10 no.4
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• pp.313-319
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• 2006

Two hundred bacterial strains were isolated from the soil around healthy tomato plants in a polyvinyl house, where most of the other plants showed bacterial wilt symptoms. The strains were screened in vitro for their antibacterial activity. Among them, a strain, KPB3 showed strong bactericidal activity against bacterial wilt pathogen, Ralstonia solanacearum. The strain KPB3 was identified using physiological and biochemical tests, and 16S rRNA analyses. Based on these tests, the strain was found to be closer to genus Paenibacillus. To control the bacterial wilt caused by R. solanacearum, greenhouse experiments were conducted to determine the effectiveness of the Paenibacillus strain KPB3. Drench application of this strain ($4{\times}10^8$ CFU $mL^{-1}$) into the pots containing tomato plants, post-inoculated with the pathogen, R. solanacearum could drastically reduce the disease severity, compared to the non-treated plants. To evaluate effectiveness of this strain under field conditions, experiments were carried out in polyvinyl houses infested with R. solanacearum, during spring and autumn of the year 2006. It was observed that, during spring, bacterial wilt was more prevalent compared to the autumn. During spring, 50.9% disease incidences occurred in non-treated controls, while, Paenibacillus strain KPB3 treated plants showed 24.6% disease incidences. Similarly, during autumn, around 17.2% plants were infected with bacterial wilt in non- treated polyvinyl houses, compared to the Paenibacillus strain KPB3 treated plants, which showed 7.0% disease incidences. These results demonstrated that, Paenibacillus strain KPB3 is a potential biological control agent against bacterial wilt caused by R. solanacearum, effective under greenhouse as well as field conditions. This is the first report showing biocontrol of R. solanacearum using a Paenibacillus spp. under field conditions.