• Microbiology and Biotechnology Letters
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• v.44 no.2
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• pp.163-170
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• 2016

Strains of lactic acid bacteria were isolated from a variety of fermented foods collected in Korea. The strain L2167 showed a strong antipathogenic activity against Bacillus cereus, Listeria monocytogenes, Salmonella Typhimurium, Staphylococcus aureus, and Staphylococcus epidermidis. L2167 was identified as Lactobacillus plantarum by sequence analysis of its 16S rRNA gene. Scanning electron microscopy revealed rough and wrinkled morphology of B. cereus, L. monocytogenes, S. Typhimurium, S. aureus, and S. epidermidis cell membranes after treatment with a crude cell extract of L. plantarum L2167, indicating that Lactobacillus plantarum L2167 might destroy the cell membrane of pathogenic bacteria. The optimal temperature and initial medium pH for Lactobacillus plantarum L2167 growth were 35℃ and 5.5, respectively. Lactobacillus plantarum L2167 was more sensitive to NaCl than Lactobacillus plantarum KCTC21004, used as a control strain. Lactobacillus plantarum L2167 is expected to be developed as a prominent starter strain for efficient inhibition of growth of pathogens.

• Korean Journal of Food Science and Technology
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• v.41 no.4
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• pp.399-404
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• 2009

The goal of this study was to improve the quality of cheonggukjang by the optimization of the inoculation methods of the Bacillus subtilis (B. subtilis) and Lactobacillus plantarum (L. plantarum) strains. In order to optimize the mixed cultivation of B. subtilis and L. plantarum, the B. subtilis strain was inoculated into steamed soybeans after cultivation of L. plantarum. Inoculation size of B. subtilis was changed to the simultaneous inoculation method in order to stimulate the growth of the L. plantarum in cheonggukjang. The viable cell count of L. plantarum increased from $2{\times}10^7$ CFU/g to $2-6{\times}10^8$ CFU/g and B. subtilis grew to $9{\times}10^8$ CFU/g. These results showed that 2 strains were successfully able to grow in the steamed soybean for good quality of cheonggukjang by optimization of the inoculation methods. The sensory evaluation indicated that a favorable aroma and overall acceptance of cheonggukjang by the optimized mixed cultivation of B. subtilis and L. plantarum, which was relatively higher than those of cheonggukjang by single strain inoculation of B. subtilis.

• Journal of Microbiology and Biotechnology
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• v.26 no.5
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• pp.975-987
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• 2016

Lactobacillus plantarum (L. plantarum) is a representative probiotic. In particular, L. plantarum is the first commensal bacterium to colonize the intestine of infants. For this reason, the initial settlement of L. plantarum can play an important role in determining an infant's health as well as their eventual health status as an adult. In addition, L. plantarum combats pathogenic infections (such as Escherichia coli (E. coli), one of the early pathogenic colonizers in an unhealthy infant gut) by secreting antimicrobial substances. The aim of this research was to determine how L. plantarum combats E. coli infection and why it is a representative probiotic in the intestine. Consequently, this research observed that E. coli releases uracil. L. plantarum specifically recognizes E. coli-derived uracil, which increases the growth rate and production of antimicrobial substance of L. plantarum. In addition, through the inhibitory activity test, this study postulates that the antimicrobial substance is a protein and can be considered a bacteriocin-like substance. Therefore, this research assumes that L. plantarum exerts its antibacterial ability by recognizing E. coli and increasing its growth rate as a result, and this phenomenon could be one of the reasons for L. plantarum settling in the intestine of infants as a beneficial bacterium.

• Korean Journal of Food Science and Technology
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• v.50 no.6
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• pp.572-580
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• 2018

Biologically active substances including gamma-aminobutryric acid (GABA) were added into whey by co fermentation using Bacillus subtilis HA and Lactobacillus plantarum EJ2014. The first fermentation using B. subtilis HA with 5% monosodium glutamate (MSG) and 2% glucose enhanced the production of poly-${\gamma}$-glutamic acid (PGA), resulting in higher consistency of $4.09Pas^n$ as well as whey protein peptides. After the second fermentation using L. plantarum EJ2014, the remaining MSG (3.40%) as a precursor was completely converted to 2.21% GABA. Furthermore, the lactose content in whey decreased from 6.73 to 3.68% after co-fermentation, and the tyrosine content increased from 20.47 to 38.24%. Peptides derived of whey proteins were confirmed by SDS-PAGE. Viable cell counts of B. subtilis and L. plantarum were 5.83 log CFU/mL and 9.20 log CFU/mL, respectively. Thus, co-fermentation of whey could produce the novel food ingredient fortified with biologically active compounds including GABA, ${\gamma}$-PGA, peptides, and probiotics.

• Korean Journal of Microbiology
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• v.46 no.4
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• pp.375-382
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• 2010

In present study, five strains of Lactobacillus acidophilus GK20, Lactobacillus brevis GK55, Lactobacillus paracasei GK74, Lactobacillus plantarum GK81, and Leuconostoc mesenteroides GK104 isolated from the mustard leaf kimchi were investigated for resistance to reactive oxygen species (ROS) and antioxidant activity. L. acidophilus GK20, L. brevis GK55, L. paracasei GK74, and L. plantarum GK81 were resistant to hydrogen peroxide (0.5 mM), showing a survival rate of 50% or more. In particular, L. acidophilus GK20 and L. paracasei GK74 were the most superoxide anions-resistant and L. paracasei GK74 and L. plantarum GK81 were most likely survive hydroxyl radicals. Meanwhile, the intracellular cell-free extract (ICFE) from L. plantarum GK81 exhibited significantly higher DPPH radical scavenging values ($96.4{\pm}2.8%$) than the intact cells (IC). The ICFE of L. plantarum GK81 showed the highest superoxide radical scavenging ability and chelating activity for $Fe^{2+}$ ions among the 5 lactic acid bacteria (LAB) tested, and IC and ICFE from L. plantarum GK81 demonstrated excellent reducing activity, which was higher than those of BHA and vitamin C as a positive control.

• Microbiology and Biotechnology Letters
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• v.45 no.4
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• pp.305-310
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• 2017

Twelve lactic acid bacteria harboring ${\alpha}$-rhamnosidase (EC 3.2.1.40) activity were isolated from traditional Korean foods. The 6 strains (Weissella confuse [n = 1], Lactobacillus pentosus [n = 1], and Lactobacillus plantarum [n = 4]) with the highest rhamnosidase activity were selected for bioconversion of an extract of wood-cultivated ginseng. The L. plantarum MBE/L2990 strain increased ginsenoside content (0.58 mg for Rg1 and 0.24 mg for Rg5) and showed higher bioconversion activity than the control strain L. plantarum KCTC21004 (56% and 42% increase for Rg1 and Rg5, respectively). L. plantarum MBE/L2990 was deposited at the Korean Collection for Type Cultures as Lactobacillus plantarum KCTC18529P.

• 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 Dairy Science and Biotechnology
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• v.38 no.4
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• pp.207-221
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• 2020

This study aimed to investigate the physiological characteristics and anti-obesity effects of milk fermented by L. plantarum KI134. The lipase, α-amylase, and α-glucosidase inhibitory activities of milk fermented by L. plantarum KI134 was 94.57±1.25%, 9.44±2.85%, and 2.74±1.24% (10 fold dilution), respectively. L. plantarum KI134 showed higher sensitivity to clindamycin and erythromycin in comparison to sixteen different antibiotics. It demonstrated the highest resistance toward ampicillin and vancomycin. The strain showed higher β-galactosidase, leucine arylamidase, valine arylamidase, acid phosphatase, β-glucosidase, and N-acetyl-β-glucosaminidase activities compared to other enzymes. It also did not produce carcinogenic enzymes, such as β-glucuronidase. The survival rate of L. plantarum KI134 in 0.3% bile was 96.90%. Moreover, the strain showed a 91.45% survival rate at a pH of 2.0. L. plantarum KI134 has resistance to Escherichia coli, Salmonella Typhimurium, Listeria monocytogenes, and Staphylococcus aureus at the rates of 70.00%, 68.18%, 59.05%, and 40.63%, respectively. L. plantarum KI134 (23.01%) showed higher adhesion ability than the positive control (16.32%) L. rhamnosus GG. These results demonstrated that milk fermented by L. plantarum KI134 demonstrated an anti-obesity effect under in vitro conditions, with confirmed potential as a probiotic.

• Food Science of Animal Resources
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• v.27 no.3
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• pp.363-370
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• 2007

In order to identify probiotic microorganisms, 25 isolates of Lactobacillus sp. were selected from kimchi based on their growth rates, lactic acid production and salt tolerance. The isolate JK-01 was identified as Lactobacillus plantarum by the API kit and 16S rDNA analysis (99.9% of homology), and named as L. plantarum JK-01. The maximum number of L. plantarum JK-01 was reached at 18 hr fermentation in MRS broth and the pH gradually decreased to 4.5. L. plantarum JK-01 showed high enzyme activities for xylanase, amylase, protease, and phytase on MRS agar plates containing each substrate. L. plantarum JK-01 showed high resistance to acidic pH and bile salts, and grew well even at pH 2.0 and 1.0% bile salt. In particular, L. plantarum JK-01 showed high heat stability as shown by $3.3{\times}10^3$ CFU/mL at $60^{\circ}C$. The isolate showed remarkable antimicrobial activity against E. coli in MRS broth based on its disappearance after 18 hr and clear zone formation using a paper disk assay. These results suggest that L. plantarum JK-01 may be probiotic in nature.

• Microbiology and Biotechnology Letters
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• v.49 no.1
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• pp.18-23
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• 2021

The aim of this study was to determine the production of folate, short chain fatty acids (SCFAs), and antimicrobial activity exhibited by Lactobacillus plantarum G72 for potential dietary application in pregnant women. L. plantarum G72 has been reported to possess characteristic activities and functionality including β-galactosidase activity and antioxidant activities. L. plantarum G72 showed antibacterial activity against pathogenic bacteria (Listeria monocytogenes ATCC 15313, Salmonella typhimurium P99, Escherichia coli ATCC 25922, and Staphylococcus aureus KCCM 11335) using a modified method, and formation of the largest inhibition zone was observed against S. aureus KCCM 11335 (12.0-17.0 mm). The adherence of four food-borne pathogenic bacteria to HT-29 cells was inhibited by L. plantarum G72 (0.13 to 0.92 log CFU/ml). The most considerable inhibition of adherence to HT-29 cells was observed by using L. plantarum G72 against S. typhimurim P99. Additionally, folate production by L. plantarum G72 was 50.1 ng/ml, and L. plantarum G72 produced relatively more lactic acid (11,176.73 mg/kg) than acetic, propionic, or butyric acids. Therefore, the results of this study suggest that L. plantarum G72 may serve as a multifunctional food additive in the health industry.