• 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.

• The Korean Journal of Community Living Science
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• v.26 no.4
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• pp.633-645
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• 2015

This study investigates the genotoxicity of crude antifungal compounds produced by Lactobacillus plantarum AF1 (L.plantarum AF1) and Lactobacillus plantarum HD1 (L. plantarum HD1) isolated from kimchi. The genetic toxicity of crude antifungal compounds was evaluated in bacterial reverse mutation in Salmonella and Escherichia spp., chromosome aberrations in Chinese hamster lung cells, and micronucleous formations in mice. In bacterial reversion assays with Salmonella Typhimurium TA98, TA100, TA1535, TA1537, and WP2uvrA, crude antifungal compounds did not increase the number of revertant colonies in both the absence and presence of the 59 metabolic activation system. In the chromosome aberration test with Chinese hamster lung cells, crude antifungal compounds showed no increase in the frequency of chromosome aberrations in the short-period test with/without the S9 mix or in the continuos test. In the in vivo mouse micronucleus assay, crude antifungal compounds showed no increase in the frequency of polychromatic erythrocytes with micronuclei. The results show that crude antifungal compounds produced by L. plantarum AF1 and L. plantarum HD1 did not induce any genotoxicity.

• Preventive Nutrition and Food Science
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• v.9 no.4
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• pp.324-329
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• 2004

In order to investigate the molecular mechanism of $\gamma$-aminobutyric acid (GABA) production in lactic acid bacteria, we cloned a glutamate decarboxylase (GAD) gene from Lactobacillus plantarum using polymerase chain reaction (PCR). One PCR product DNA was obtained and inserted into a TA cloning vector with a T7 promoter. The recombinant plasmid was used to transform E. coli. The insertion of the product was con­firmed by EcoRI digestion of the plasmid purified from the transformed E. coli. Nucleotide sequence analysis showed that the insert is a full-length Lactobacillus plantarum GAD and that the sequence is $100\%$ and $72\%$ identical to the regions of Lactobacillus plantarum GAD and Lactococcus lactis GAD sequences deposited in GenBank, accession nos: NP786643 and NP267446, respectively. The amino acid sequence deduced from the cloned Lactobacillus plantarum GAD gene showed $100\%$ and $68\%$ identities to the GAD sequences deduced from the genes of the NP786643 and NP267446, respectively. To express the GAD protein in E. coli, an expression vector with the GAD gene (pkk/GAD) was constructed and used to transform the UT481 E. coli strain and the expression was confirmed by analyzing the enzyme activity. The Lactobacillus plantarum GAD gene obtained may facilitate the study of the molecular mechanisms regulating GABA metabolism in lactic acid bacteria.

• Journal of Food Hygiene and Safety
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• v.30 no.4
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• pp.372-375
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• 2015

A lactic acid bacterium LP2 strain, which was previously isolated from a natural cheese, was confirmed to produce 1,4-dihydroxy-2-naphthoic acid (DHNA), a bifidogenic growth factor. The strain was identified as Lactobacillus plantarum (99% identity) by a homology search of the 16S rRNA gene sequence and named Lactobacillus plantarum LP2. The culture supernatant of the strain presented an antimicrobial activity against Helicobacter pylori KCTC 12083, where the DHNA might have influenced on the activity.

• Journal of The Korean Society of Grassland and Forage Science
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• v.44 no.1
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• pp.50-57
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• 2024

Silage inoculants, crucial in modern silage production, comprise beneficial microorganisms, primarily lactic acid bacteria (LAB), strategically applied to forage material during ensiling. This study aimed to compare the effectiveness of various inoculants produced by different companies. Five treatments were evaluated, including a control group: T1 (Lactobacillus plantarum), T2 (Lactobacillus plantarum + Pediococcus pentosaceus), T3 (Lactobacillus plantarum + Pediococcus pentosaceus + Lactobacillus buchneri), T4 (Lactobacillus plantarum + Lactobacillus acidophilus + Lactobacillus bulgaricus), and T5 (Lactobacillus plantarum + Pediococcus pentosaceus + Enterococcus faecium). Italian ryegrass was harvested at the heading stage and treated with these silage inoculants. Samples were collected over a 60-day ensiling period. Co-inoculation with L. plantarum and P. pentosaceus (T2) resulted in significantly higher CP compared to the control group co-inoculation exhibited with resulted in Lactobacillus plantarum and Pediococcus pentosaceus in the T2 treatment exhibited higher CP content of 106.35 g/kg dry matter (DM). The T3 treatment, which included heterofermentative bacterial strains such as Lactobacillus buchneri, exhibited an increase in acetic acid concentration (11.15 g/kg DM). In the T4 treatment group, which utilized a mixed culture of Lactobacillus acidophilus and Lactobacillus bulgaricus, the NH₃-N/TN content was observed to be the lowest (20.52 g/kg DM). The T5 containing Enterococcus faecium had the highest RFV (123) after 60 days. Expanding upon these findings, the study underscores not only the beneficial effects of particular inoculant treatments on silage quality but also underscores the potential of customized inoculation strategies in maximizing nutrient retention and overall silage preservation.

• The Korean Journal of Food And Nutrition
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• v.26 no.2
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• pp.280-286
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• 2013

This study was performed to investigate the effect of types of microorganisms on the antioxidant activity of soybean yogurt by a single or mixed culture of Bacillus subtilis and Lactobacillus plantarum isolated from chunggukjang and kimchi. The fermented soybean milk by Bacillus subtilis exhibited the highest values of total polyphenol, DPPH radical scavenging activity, reducing power and nitrite scavenging activity compared to those of Lactobacillus plantarum or mixed culture of Bacillus subtilis/Lactobacillus plantarum. As the amount of tomato extract was added to the soybean milk, various antioxidant parameters, such as total polyphenol, DPPH radical scavenging activity, reducing power and nitrite scavenging activity, were linearly increased.

• Korean journal of food and cookery science
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• v.22 no.3 s.93
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• pp.270-281
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• 2006

The study investigated the effect of prefermentation of Bifidobacteria longum and Lactobacillus plantarum on baking quality. Firstly, two kinds of prefermentation were cultured using two lactic acid bacteria, Bifidobacteria longum and Lactobacillus plantarum. White pan bread baked with dough that had undergone these two prefermentation methods was compared with that baked with a non-prefermented control. The physicochemical properties of the three breads were analyzed, and then the physicochemical and sensory properties of the dough and baked bread were cross-analyzed. The pH prefermentation of Bifidobacteria longum was lower than that of Lactobacillus plantarum, whereas the titratable acidity was higher. Compared to the results from analyzing the prefermentation of Lactobacillus plantarum, the prefermentation of Bifidobacteria longum was expected to give positive effects on enriching the bread flavor by creating acetic acid at a level three- to eight-fold higher than that of Lactobacillus plantarum. According to the mixogram data, the optimum ending time for both Bifidobacteria longum prefermentation and Lactobacillus plantarum was around 4.5 to 5 minutes. The speed of dough materialization decreased with increasing prefermentation culture time. The baked bread with added Bifidobacteria longum had a higher water content. However, the other contents were not influenced by prefermentation, but were by culture time. The specific loaf volume, oven spring and baking lass rate all peaked at 20 hours after culture for both prefermentation cultures. The sensory test results indicated the highest prefermentation for the bread baked with prefermented Bifidobacteria longum doughwith a culture time ranging from 20 to 26 hours. In addition, the bread baked with prefermented Lactobacillus plantarum dough gave the highest preference when cultured for 20 hours.

• Journal of Animal Science and Technology
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• v.54 no.6
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• pp.435-442
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• 2012

This study was conducted to isolate and identify the lactic acid bacteria (LAB) from spent mushroom substrates (SMS) for the effective anaerobic fermentation to utilize SMS as an animal feed and to determine the optimal medium conditions for their growth. At first, a total of 23 strains were isolated from the ensiled SMS based on the LAB counts and pH tested. Then, a total of 16 strains which rapidly produce lactate and decreased the pH, were selected for a screening test. The optical density (OD), pH, and yellow clear zone were tested for the selected 16 strains. Among the strains, KU5 strain had wider yellow clear zone and lower pH and KU13 strain had higher OD at 24 hr of incubation and wider yellow clear zone compared to other strains and control strain (Lactobacillus plantarum KCCM 12116). Accordingly, KU5 and KU13 strains were finally selected. The KU5 and KU13 were identified as Lactobacillus plantarum by the 16S rRNA sequencing. The KU5 strain was named as Lactobacillus plantarum KU5, and the KU13 strain was named as Lactobacillus plantarum KU13. Lactobacillus plantarum KU5 and Lactobacillus plantarum KU13 were registered at the National Center for Biotechnology Information (NCBI). Access number of Lactobacillus plantarum KU5 was HQ542227 and that of Lactobacillus plantarum KU13 was HQ542228. The optimal medium conditions for growth of KU5 and KU13 were soybean meal 2% and formulated feed 2%, respectively.

• 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.

• Korean Journal of Microbiology
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• v.54 no.3
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• pp.295-298
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• 2018

Lactobacillus plantarum is a Gram-positive, facultative heterofermentative, nonspore-forming nonmotile bacterium found in a wide range of environmental niches. Here we present the complete genome sequence of L. plantarum SK151 isolated from kimchi, which shows high adhesion to intestinal epithelial cells. The genome is 3,231,249 bp in length and has a GC content of 44.6%. The genome contains genes related to cell adhesion and a complete operon for riboflavin biosynthesis.