• Journal of Microbiology and Biotechnology
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• v.33 no.5
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• pp.644-655
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• 2023

Safety assessment and functional analysis of probiotic candidates are important for their industrial applications. Lactiplantibacillus plantarum is one of the most widely recognized probiotic strains. In this study we aimed to determine the functional genes of L. plantarum LRCC5310, isolated from kimchi, using next-generation, whole-genome sequencing analysis. Genes were annotated using the Rapid Annotations using Subsystems Technology (RAST) server and the National Center for Biotechnology Information (NCBI) pipelines to establish the strain's probiotic potential. Phylogenetic analysis of L. plantarum LRCC5310 and related strains showed that LRCC5310 belonged to L. plantarum. However, comparative analysis revealed genetic differences between L. plantarum strains. Carbon metabolic pathway analysis based on the Kyoto Encyclopedia of Genes and Genomes database showed that L. plantarum LRCC5310 is a homofermentative bacterium. Furthermore, gene annotation results indicated that the L. plantarum LRCC5310 genome encodes an almost complete vitamin B₆ biosynthetic pathway. Among five L. plantarum strains, including L. plantarum ATCC 14917^T , L. plantarum LRCC5310 detected the highest concentration of pyridoxal 5'-phosphate with 88.08 ± 0.67 nM in MRS broth. These results indicated that L. plantarum LRCC5310 could be used as a functional probiotic for vitamin B₆ supplementation.

• Journal of Life Science
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• v.22 no.5
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• pp.575-581
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• 2012

This study was conducted to develop an economical optimum medium composition for the mass production of $Lactobacillus$ $plantarum$ and $Lactobacillus$ $reuteri$, livestock probiotics. Medium ingredient factors were selected on the basis of MRS broth composition, and the 15 ingredient variables were as follows: sucrose, glucose, molasses, yeast extract, corn steep liquor, soy peptone, dipotassium phosphate, manganese chloride, magnesium chloride, tween 80, sodium chloride, sodium acetate, ammonium citrate, sodium sulphate, and ferrous sulphate. The Plackett Burman design, consisting of 20 runs, was employed for the analysis of ingredient effects on cell growth of $L.$ $plantarum$ and $L.$ $reuteri$. As a result, sucrose, glucose, molasses, yeast extract, corn steep liquor, soy peptone, sodium acetate, and ammonium citrate positively influenced the growth of $L.$ $plantarum$. Additionally, yeast extract, soy peptone, $K_2PHO_4$, and tween 80 positively influenced the growth of $L.$ $reuteri$. Positive effects were found from sucrose, yeast extract, and soy peptone in the integrated analysis of the effects of both $L.$ $plantarum$ and $L.$ $reuteri$. Finally, effective medium components for both strains were found as follows: sucrose (20.0 g/l), glucose (5.0 g/l), soy peptone (11.0 g/l), yeast extract (5.0 g/l), $K_2PHO_4$ (0.2 g/l), $CH_3COONa$ (2 g/l), and $MgCl_2$ (0.02 g/l).

• Applied Biological Chemistry
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• v.39 no.6
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• pp.437-442
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• 1996

Two strains of Lactobacillus(L.) casfi and one strain of L. Pentosus, which were isolated from pickles, were used to investigate in studing their characteristics of ${\beta}-galactosidase$. The preferable carbon sources and pH of the MRS media for enzyme production from L. casei No.10 was found to be 1.0% lactose and pH 7.5, from L. Pentosus No.63 was 1.0% galactose and pH 7.5, and from L. casei No.36 was 1.0% lactose and pH 6.5, respectively. The maximum enzyme production from each strain was found after 48 hours culture at $30^{\circ}C$ in a medium with preferable carbon source. The optimum reaction temperature with substrate for ${\beta}-galactosidase$ activity was found at $60^{\circ}C$ for all three strains . The stability of enzyme from L. casei No.36 was found to be at $45^{\circ}C$, from L. Pentosus No.63 was found at $55^{\circ}C$. This stability from L. casei No.36 was found at $40^{\circ}C$, but it was reduced to 60% at $55^{\circ}C$. These stabilities of enzymes remained about 90% at $40^{\circ}C$ for all three strains. The optimal pH for enzyme activities was found to be pH 6.5 for all three strains. Enzyme activity remained over 90% for L. casei No.10 at $pH\;5.0{\sim}6.0$, for L. casei No.36 at $pH\;5.0{\sim}8.0$, and for L. pentosus No.63 at $pH\;6.0{\sim}7.0$.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.681-687
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• 2007

This study was designed to examine the suitable characteristics of potential probiotic bacteria. Possible probiotic bacteria, including Lactobacillus acidophilus DDS-1, Lb. acidophilus B-3208, Bifidobacterium bifidum KCTC 3357, Lb. plantarum, Leuconostoc mesenteroides ssp. mesenteroides ATCC 8293, and Lactococcus lactis ssp. lactis ATCC 7962 were selected. We then measured their acid and bile tolerances, adhesion properties in the gastrointestinal tract, antimicrobial activity against pathogenic bacteria, and immunomodulation activity. The acid tolerances of Lb. acidophilus DDS-1, Lb. acidophilus B-3208, Lb. plantarum, and Leu. mesenteroides ssp. mesenteroides ATCC 8293, in PBS (pH 2.5) for 2 hr, were high enough that 50% of the inocula survived. The bile tolerances of all bacteria, except Lc. lactis ssp. lactis ATCC 7962, were also observed at a 3% oxgall concentration in MRS broth. The results of the adhesion property assay showed that the total binding affinities of Lb. acidophilus DDS-1, Lb. acidophilus B-3208, and B. bifidum were about three times higher than those of the other bacteria. In testing their antimicrobial activities against pathogens, Lb. acidophilus B-3208, B. bifidum KCTC 3357, and Lb. plantarum inhibited the growth of pathogenic bacteria. For their immunomodulation activity, the cell wall fractions from Lb. acidophilus DDS-1 and Lb. acidophilus B-3208 showed the highest bone marrow cell proliferation activities. However, the cell wall fractions of Lb. acidophilus DDS-1 and B. bifidum, and the cytosol fraction of Lc. lactis ssp. lactis ATCC 7962 showed higher macrophage stimulation activities than those of the other bacteria. Since Lb. acidophilus DDS-1 and Lb. acidophilus B-3208 satisfy the requirements for probiotics, they can be considered suitable probiotic bacteria.

• Korean Journal of Food Science and Technology
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• v.48 no.3
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• pp.231-240
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• 2016

The purpose of this study was to investigate the effect of exopolysaccharide (EPS)-producing Leuconostoc and Weissella isolates from kimchi as a probiotic starter and replacement for thickening agents such as pectin and gums in yogurt. Potential probiotic isolates were first screened for their acid and bile tolerance, and then evaluated for antimicrobial activity against Escherichia coli and Salmonella Typhimurium. When the selected Leuconostoc or Weissella isolates were co-inoculated in yogurt without a thickening agent, the yogurt with 4% sucrose produced lower syneresis values than the control and had higher EPS yields. The isolates were able to survive at a level of $10^6CFU/mL$ when incubated at $4^{\circ}C$ for 12 days. This study shows that EPS-producing Leuconostoc and Weissella strains have the potential to produce a synbiotic yogurt.

• Journal of Life Science
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• v.22 no.2
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• pp.251-258
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• 2012

The purpose of this study was to investigate the probiotic properties of lactic acid bacterial strains isolated from animal feces. BCNU 9041 and BCNU 9042 isolates were assigned to Lactobacillus brevis on the basis of their physiological properties and 16S ribosomal DNA sequences analysis. They were confirmed as safe bioresources because of their non-hemolytic activities and non-production of harmful ${\beta}$-glucosidase, ${\beta}$-glucuronidase, tryptophanase, or urease. These isolates were also highly resistant to acid (at pH 2.5) and bile acids (at concentration of 0.3%, 0.6%, and 1% oxgall). In addition, they exhibited good antibacterial activity against food-borne bacteria, especially Bacillus cereus, Listeria monocytogenes, and Shigella sonnei. Furthermore, it was demonstrated that they have the highest levels of hydrophobicity and that they showed bile salt hydrolytic and cholesterol assimilation activity. These results suggest that BCNU 9041 and 9042 have good potential for application in functional foods and health-related products.

• Microbiology and Biotechnology Letters
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• v.26 no.2
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• pp.151-160
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• 1998

The Leuconostoc paramesenteroides dominated at refrigeration temperature range was isolated from kimchi, and improved its growth properties by mutation for competitive growth against Lactobacillus plantarum at lower pH. It was found that the minimal pH for the wild type Leuconostoc paramesenteroides Pw growth was pH 4.5 adjusted with HCI and pH 5.0 adjusted with organic-mixture (lactic acid:acetic acid=1:2), respectively. The mutant P-100 could grow in pH 4.0, 4.5, respectively, in MRS broth. Two strains Pw and P-100 were added into kimchi as starter and compared the quality characteristics of kimchi. The total acceptability of Pw and P-100 inoculated kimchi were evaluated better than that of control kimchi (no starter added) by sensory test and extended the optimal pH range of kimchi up to about 2.2, 2.5 times, respectively. In kimchi added P-100, the succinic acid was more abundant than others and the total number of Lactobacillus plantarum was down about 2.5 times in contrast to control kimchi.

• Journal of Food Hygiene and Safety
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• v.19 no.3
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• pp.151-160
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• 2004

Enterococcus faecium MJ5-14 isolated from Meju produced a bacteriocin, which was antagonistic towards Listeria monocytogenes. Bacteriocin activity reached a maximum (640 BU/mL) after incubation for 12 hr, the early stationary phase, then dropped after the late stationary phase. Bacterocin of E. faecium MJ5-14 was extremely active against a wide range of Listeria species, including L. monocytogenes with sensitives up to about 640 BU/mL. In case of mixed culture with 105 CFU/mL L. monocytogenes and 105 CFU/mL E. faecium MJ5-14, the inhibitory effect against L. monocytogenes at $37^{\circ}C$ was higher than at $25^{\circ}C$. The mode of action was identified as bactericidal, because the addition of 100 BU/mL this bacteriocin to cell suspensions of L. monocytogenes KCTC 3569, led to a marked decrease in the number of viable cells. Further, when held in contact with bacteriocin of E. faecium MJ15-14 for 12 hr, L. monocytogenes KCTC 3569 displayed the disruption of the cells and an important efflux of the intracellular material.

• Journal of Microbiology and Biotechnology
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• v.16 no.8
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• pp.1201-1209
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• 2006

The purpose of this study was to isolate probiotic lactic acid bacteria (LAB) that produce bile salt hydrolase (BSH), and to evaluate its effects on serum cholesterol level. One-hundred-twenty bacterial colonies were initially isolated from human feces, and five strains were selected after screening based on their resistance to acids, tolerance against bile salts, and inhibitory activity on Escherichia coli. The Lactobacillus plantarum strain with the highest level of BSH activity was identified using 16S rRNA sequences, and was named L. plantarum CK 102. L. plantarum CK 102 at a level of 1.36$\times$10$^8$cfu/ml survived in pH 2 buffer for 6 h and exhibited excellent tolerance for bile salt. Coculturing the strain with E. coli in MRS broth resulted in strong inhibition against growth of E. coli at 18 h. Furthermore, the potential effect of CK 102 on serum cholesterol level was evaluated in rats. Thirty-two rats [Sprague-Dawley (SD) male, 129$\pm$l g, 5 weeks old] were divided into four groups of eight each. For six weeks, Group 1 was fed a normal diet (negative control); Group 2 was fed a cholesterol-enriched diet (positive control); Group 3 was fed a cholesterol-enriched diet plus L. plantarum CK 102 at 1.0$\times$10$^7$cfu/ml; and Group 4 was fed a cholesterol-enriched diet plus L. plantarum CK 102 at 5.0$\times$10$^7$cfu/ml. Blood samples were collected, serum lipids were analyzed, and weights of the organs were measured. Total blood cholesterol level, triglyceride, LDL-cholesterol, and free-cholesterol values were lower in rats that were fed 1. plantarum CK 102 than in those not fed L. plantarum CK 102. This cholesterol lowering effect implies that L. plantarum CK 102 could be utilized as an additive for health-assistance foods. In conclusion, these results suggest that the 1. plantarum CK 102 isolated could be used commercially as a probiotic.

• Journal of Microbiology and Biotechnology
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• v.9 no.1
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• pp.22-31
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• 1999

Saccharomyces fermentati and Leuconostoc mesenteroides were isolated from a traditional kimchi, and then the Leu. mesenteroides was mutated to the acid-tolerant mutant Leu. mesenteroides M-l00. In the result of growth properties in MRS broth with various pHs adjusted with HCl and acid solution (latic acid:acetic acid=1:2), an acid-tolerant mutant Leu. mesenteroides M-100 showed more increased ability for growth than its wild strain at various temperatures. The strains were used as starters for the fermentation of kimchi. The experiments were performed with classified experimental groups (Group I, control kimchi; Group II, addition of YK-19 only; Group III, addition of M-100 only; Group IV, addition of mixture of M-100 and YK-19), and their pH, total acidity, reducing sugars content, organic acid productivity, organoleptic tests, and microfloral changes were compared. As a result, in pH and acidity, the optimal ripening period of Group IV was about 13.5 days (i.e. from the 8.5 to 22 days of fermentation). This result indicates that the optimal ripening period of Group IV was about 1.5 times longer than that of Group I. Furthermore, Group IV was edible to 28 days of fermentation. In addition, high contents of succinc acid was observed in Group IV. Group IV was also highly ranked on the organoleptic test. During the fermentation of kimchi, the number of Leuconostoc sp. in group I reduced after 7 days; however, the number of Leuconostoc sp. in Group II, III, and IV decresed after 14 days of fermentation. An especially high number of Leu. sp. was observed in Group IV, and this gave better flavor of kimchi than any other during the whole fermentation period. Citric acid, tartaric acid, succinic acid, fumaric acid, and lactic acid were detected in the kimchi, and a significant increase in the concentration of lactic acid during fermentation was observed in the all experimental groups.