• Journal of Life Science
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• v.12 no.6
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• pp.812-820
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• 2002

In order to understand stress response of Leuconostoc mesenteroides against lactic acid, a new Leuconostoc sp. which has acid tolerance was isolated from various Kimchi samples. And it identified as Leuconostoc mesenteroides LM3 by comparing its fatty acid composition with reference strain. Its growth pattern was investigated by adding a given concentration of lactic acid at the lag phase to the stationary phase. In the DeMan, Rogosa, Sharpe (MRS) media containing over 0.4% (final v/v) lactic acid, this strain slowed slowly After exposure of the stationary phase cells to 4% of lactic acid for 60 min, this strain could survive, whereas a reference strain, Leuconostoc mesenteroides KCTC3505, showed no survival. And changes of trehalose concentration, the activity of trehalase and ATPase in the growth of Leuconostoc mesenteroides LM3 after addition of 0.6% (final v/v) lactic acid were investigated : After exposure to lartic acid, trehalose concentration in this strain was increased in comparison with no treatment, but its trehalase activity was not changed. And its ATPase activity was constant, and intracellular pH was almost constant. This result meant Leuconostoc mesenteroides LM3 should have a tolerance against lactic acid. It remains to further study the mechanism of this acid tolerance.

• Korean journal of food and cookery science
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• v.21 no.1 s.85
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• pp.33-39
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• 2005

The present study was carried out to develop sausage using Leuconostoc citreum which was isolated from Kimchi. Leuconostoc citreum was added to sausage at three concentrations of 1, 3 and $5\%$, and was stored at $10^{\circ}C$ for 40 days. The pH of the sausage containing Leuconostoc citreum was similar to the control group. The TBA value of the group containing Leuconostoc citreum was lower than the control group. However, the TBA value of the control group steadily increased after 10 days of storage, and there were only minor changes in the groups containing Leuconsostoc citreum. In addition, the TBA value of the sausages employed for the present study was either 0.46MA mg/kg or less than that over the entire period of storage. The residual nitrite value was 47.1 ppm at the beginning of the storage in the control group and was 32.5, 32.2 and 30.9 ppm in the groups containing Leuconostoc citreum. The sausages with TBA values higher than 70 ppm are not permitted in Korea. With regards totexture characteristics, it was observed the hardness was lower in the groups containing Leuconostoc ctireum than in the control group while springiness was almost the same in both the groups, but the group containing $1\%$ Leuconostoc citreum showed the best springiness. Both gumminess and brittleness were lower in the groups containing Leuconostoc citreumthan than in the control group. It was inferred that with an increase in the concentration of Leuconostoc citreum there was a decrease in the value of gumminess and brittleness. The results of the sensory evaluation were generally better in the groups containing Leuconostoc citreum than the control group. The sausage containing $3\%$ Leuconostoc citreum obtained the most excellent scores.

• Journal of Microbiology and Biotechnology
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• v.23 no.6
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• pp.837-842
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• 2013

A cryptic plasmid, pMBLR00, from Leuconostoc mesenteroides subsp. mesenteroides KCTC 3733 was isolated, characterized, and used for the construction of a cloning vector to engineer Leuconostoc species. pMBLR00 is a rolling circle replication plasmid, containing 3,370 base pairs. Sequence analysis revealed that pMBLR00 has 3 open reading frames: Cop (copy number control protein), Rep (replication protein), and Mob (mobilization protein). pMBLR00 replicates by rolling circle replication, which was confirmed by the presence of a conserved double-stranded origin and single-stranded DNA intermediates. An Escherichia coli-Leuconostoc shuttle vector, pMBLR02, was constructed and was able to replicate in Leuconostoc citreum 95. pMBLR02 could be a useful genetic tool for metabolic engineering and the genetic study of Leuconostoc species.

• Journal of Microbiology and Biotechnology
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• v.29 no.4
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• pp.558-561
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• 2019

This study aimed to understand the survival and growth patterns of bacteriophage-sensitive Weissella and Leuconostoc strains involved in kimchi fermentation. Dongchimi kimchi was prepared, and Weissella and Leuconostoc were co-cultivated in the dongchimi broth. Weissella cibaria KCTC 3807 growth was accompanied by rapid lysis with an increase in the bacteriophage quantity. Leuconostoc citreum KCCM 12030 followed the same pattern. The bacteriophage-insensitive strains W. cibaria KCTC 3499 and Leuconostoc mesenteroides KCCM 11325 survived longer under low pH as their growth was not accompanied by bacteriophages. The bacteriophage lysate of W. cibaria KCTC 3807 accelerated and promoted the growth of Leuconostoc. Overall, our results show that bacteriophages might affect the viability and population dynamics of lactic acid bacteria during kimchi fermentation.

• Microbiology and Biotechnology Letters
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• v.21 no.6
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• pp.570-576
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• 1993

For the production of glucose-1-phosphate from sucrose, bacteria having sucrose phosphorylase were isolated from Kimchi. Among them, JS-05, newly isolated strain having high activity of sucrose phosphorylase was selected and identified as Leuconostoc sp. The specific activity of sucrose phosphorylase of Leuconostoc sp. JS-05 was the highest when the strain was cultured at 25C for 20 hrs in the medium (pH 7.5) containing 10 g sucrose, 5g corn steep liquor, and 2.5g yeast extract per liter.

• Journal of Microbiology and Biotechnology
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• v.32 no.3
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• pp.333-340
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• 2022

Leuconostoc has been used as a principal starter in natural kimchi fermentation, but limited research has been conducted on its phages. In this study, prophage distribution and characterization in kimchi-derived Leuconostoc strains were investigated, and phage induction was performed. Except for one strain, 16 Leuconostoc strains had at least one prophage region with questionable and incomplete regions, which comprised 0.5-6.0% of the bacterial genome. Based on major capsid protein analysis, ten intact prophages and an induced incomplete prophage of Leu. lactis CBA3626 belonged to the Siphoviridae family and were similar to Lc-Nu-like, sha1-like, phiMH1-like, and TPA_asm groups. Bacterial immunology genes, such as superinfection exclusion proteins and methylase, were found on several prophages. One prophage of Leu. lactis CBA3626 was induced using mitomycin C and was confirmed as belonging to the Siphoviridae family. Homology of the induced prophage with 21 reported prophages was not high (< 4%), and 47% identity was confirmed only with TPA_asm from Siphoviridae sp. isolate ct3pk4. Therefore, it is suggested that Leuconostoc from kimchi had diverse prophages with less than 6% genome proportion and some immunological genes. Interestingly, the induced prophage was very different from the reported prophages of other Leuconostoc species.

• Kosin Medical Journal
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• v.33 no.3
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• pp.422-430
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• 2018

Leuconostoc species are Gram-positive coccobacilli and are used in dairy products and are intrinsically resistant to vancomycin. Leuconostoc infections are rare in humans, usually occurring in immune-compromised patients. We describe 6 patients with Leuconostoc bacteremia at Dong-A university hospital between 1990 and 2015. One isolate (L. lactis) was identified to species level using 16S rRNA gene sequencing analysis. All patients had underlying diseases and 5 patients underwent procedures that interrupted the normal integumentary defense. Four patients died within 30 days after being identified as carrying Leuconostoc species.

• Microbiology and Biotechnology Letters
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• v.20 no.1
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• pp.102-109
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• 1992

The microfloral changes of lactic acid bacteria during Kimchi fermentation at 5, 20 and $30^{\circ}C$ were compared by using various selective media, and the lactic acid bacterial strains were isolated and identified. The patterns of microfloral changes in each lactic acid bacterial group, leuconostoc, lactobacilli, streptococci and pediococci, were similar at different fermentation temperature, and the changes were accelerated by increased temperature. Among them, leuconostoc and lactobacilli showed high population, and at low temperature the number of leuconostoc were higher than at high temperature. Leuconostoc and streptococci were increased in number from the beginning, but they rapidly decreased after the optimum ripening period. Pediococci increased their number after streptococci, but they were rapidly decreased later. Lactobacilli were highly distributed throughout the whole fermentation period. However, they were slightly declined as the acidity increased. Those strains of leuconostoc, streptococci, pediococci and lactobacilli were identified as Luuconostoc mesenteroida subsp. musenteroides, Streptococcus fuecalzs, S, faeciurn, Pediococcus pentosaceus, Lactobacillus plarttarum, L. sake and L. brevis. Among lactobacilli, Id. sake and L. brmk, and L. plantarum were isolated mainly at the beginning and around the overripening period of fermentation, respectively.

• Journal of Microbiology and Biotechnology
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• v.12 no.1
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• pp.166-171
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• 2002

The genus Leuconostoc is generally recognized as a favorable microorganism associated with a good taste of Kimchi and Lactobacillus plantarum is responsible for the overripening and acidification of Kimchi. A rapid and reliable PCR-based method to monitor the change of these lactic acid bacterial populations during Kimchi fermentation was attempted. A Leuconostoc-specific primer set was chosen from the conserved sequences of 16S rRNA genes among Leuconostoc species. The Lb. plantarum-specific primer set was the internal segments of a Lb. plantarum-specific probe which was isolated after randomly amplified polymorphic DNA (RAPD) analysis and tested for identification. The specificity of this protocol was examined in DNA samples isolated from a single strain. In agarose gel, as little as 10 pg of template DNA could be used to visualize the PCR products, and quantitative determination was possible at the levels of 10 pg to 100 ng template DNA. For the semi-quantitative determination of microbial changes during Kimchi fermentation, total DNAs from the 2 h-cultured microflora of Kimchi were extracted for 16 days and equal amounts of DNA templates were used for PCR. The intensities of DNA bands obtained from PCR using Leuconostoc-specific and Lb. plantarum-specific primer sets marked a dramatic contrast at the 1 ng and 100 ng template DNA levels during Kimchi fermentation, respectively. As the fermentation proceeded, the intensity of the band for Leuconostoc species increased sharply until the 5th day and the levels was maintained until the 11 th day. The sharp increase for Lb. plantarum occurred after 11 days with the decrease of Leuconostoc species. The results of this study indicate that Leuconostoc species were the major microorganisms at the beginning of Kimchi fermentation and reach their highest population during the optimum ripening period of Kimchi.

• Microbiology and Biotechnology Letters
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• v.39 no.2
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• pp.175-181
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• 2011

Kimchi is a group of traditional fermented vegetable foods in Korea and known to be the product of a natural mixed-fermentation process carried out principally by lactic acid bacteria (LAB). According to microbial results based on conventional identification, Leuconostoc mesenteroides and Lactobacillus plantarum were considered to be responsible for the good taste and over-ripening of kimchi, respectively. However, with the application of phylogenetic identification, based on 16S ribosomal RNA gene similarities, a variety of Leuconostoc and Lactobacillus species not detected in the previous studies have been isolated, together with a species in the genus Weissella. Additionally, Lactobacillus sakei has been accepted as the most populous LAB in over-ripened kimchi. In this study, Leuconostoc and Weissella species inhibiting the growth of Lb. sakei were isolated from kimchi for future applications to do with kimchi fermentation. From 25 kimchi samples, 378 strains in the genera Leuconostoc and Weissella were isolated and 68 strains identified as Lc. mesenteroides, Lc. citreum, Lc. lactis, W. cibaria, W. confusa, and W. paramesenteroides exhibited growth inhibition against Lb. sakei. Most of the strains also had antagonistic activities against Lb. brevis, Lb. curvatus, Lb. paraplantarum, Lb. pentosus, and Lb. plantarum. Their antagonistic activities against Lb. sakei were more remarkable at lower temperatures of incubation.