• Korean Journal of Microbiology
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• v.53 no.3
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• pp.180-192
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• 2017

The purpose of this study is to investigate the antioxidative and antimicrobial activities of sourdough fermented with the lactic acid bacteria (LAB) isolated from sliced radish kimchi. According to 16S rRNA gene sequence analysis, the isolated lactic acid bacteria were categorized as Leuconostoc dextranicum SRK03, Lactobacillus brevis SRK15, Pediococcus halophilus SRK22, Lactobacillus acidophilus SRK30, Lactobacillus plantarum SRK38, Leuconostoc citreum SRK 42, and Lactobacillus delbrueckii SRK60 with sequence similarity of 99%. After fermentation with L. dextranicum SRK03, L. acidophilus SRK30, L. plantarum SRK38 or L. delbrueckii SRK60 and Saccharomyces cerevisiae KCTC 7246 at $30^{\circ}C$ for 24 h LAB and yeast in sourdough were present at levels of $10^9$ and $10^7CFU/g$, respectively. In particular, the titratable acidity and ethanol and exopolysaccharide contents of sourdough fermented with L. dextranicum SRK03 were also significantly (P < 0.05) higher than those of sourdough fermented with L. acidophilus SRK30, L. plantarum SRK38, or L. delbrueckii SRK60. The sourdough fermented with L. dextranicum SRK03 and L. acidophilus SRK30 showed not only good DPPH radical-scavenging capacity but anti-lipid peroxidation activity. In addition, the viable counts of Bacillus cereus ATCC 11778 and Staphylococcus aureus ATCC 6538 in sourdough during storage for 5 days at $25^{\circ}C$ were significantly (P < 0.05) lower than those of pathogenic bacteria in the control group due to the organic acids and bacteriocin produced by L. acidophilus SRK30 strain.

• Journal of Microbiology and Biotechnology
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• v.12 no.6
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• pp.998-1001
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• 2002

Potential antitumor activity of Lactobacillus plantarum cytoplasm was examined using F9 teratocarcinoma-bearing BALB/C mice. The cytoplasmic fraction of L. plantarum was separated by sonication followed by ultracentrifugation. The fraction at a dose of 100 or 200 mg/kg/day was orally administered for 7 consecutive days before or after tumor inoculation to 16 mice. As a control, heat-killed whole cell was used at a dose of 100 mg/kg/day. Upon oral administrations of both the cytoplasm and heat-killed whole cell, when performed after and before tumor inoculation, the survival of F9-bearing mice prolonged more effectively. Administration of the cytoplasm after tumor inoculation extended the average survival days by 30 and $40\%$ at daily dosages of 100 and 200 mg/kg/day, respectively. This result suggests that the cytoplasmic fraction of L. plantarum has strong antitumor activity against mouse F9 teratocarcinoma in vivo.

• The Korean Journal of Food And Nutrition
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• v.29 no.2
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• pp.200-205
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• 2016

The aim of this work was to select suitable fermentation treatments for the efficient bioconversion of cactus (Opuntia humifusa Raf.) bioactive components with an improved radical scavenging activity for use as a nutraceutical. To obtain microorganisms for the microbial conversion of cactus, Leuconostoc mesenteroides ATCC8294, Lactobacillus plantarum KCTC 3099, Lactobacillus plantarum KERI 236 and Monascus pilosus KCCM 60029 (ATCC 22080) were used for fermentation. Fermentation by Lac. plantarum KCTC 3099 was the most effective at scavenging 1,1-diphenyl-2-picrylhydrazyl hydrate (DPPH) and 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals and reducing iron (III). In particular, uronic acid levels showed a remarkable increase in fermentation. The polyphenol and quercetin content of the fermented cactus showed large increases from $108.65{\mu}g/mL$ and $2.71{\mu}g/mL$ to $227.83{\mu}g/mL$ and $9.73{\mu}g/mL$, respectively, showing a maximum level at 36 h of fermentation with Lac. plantarum KCTC 3099. Thus, cactus fermentation with Lac. plantarum is an useful process for the enhancement of antioxidant contents and activity of fresh cactus.

• Journal of Microbiology and Biotechnology
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• v.22 no.12
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• pp.1731-1739
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• 2012

In this study, seven strains isolated from mustard leaf kimchi were screened for their tolerance to simulated gastric and bile juices, the adhesive properties to Caco-2 cells, and the inhibition ability of Salmonella Typhimurium ATCC 29631 adhesion. Lactobacillus acidophilus GK20, Lactobacillus paracasei GK74, and Lactobacillus plantarum GK81, which were resistant to bile as well as gastric juices, possessed high bile-salt hydrolase (BSH) activity towards both sodium glycocholate and sodium taurocholate. The strongest in vitro adherence of $53.96{\pm}4.49%$ was exhibited by L. plantarum GK81 followed by L. acidophilus GK20 with adhesion levels of $40.72{\pm}9.46%$. The adhesion of these strains was significantly (p < 0.05) reduced after exposure to pepsin and heating for 30 min at $80^{\circ}C$. Addition of $Ca^{2+}$ led to a significant (p < 0.05) increase of the adhesion of L. acidophilus GK20, but the adhesion ability of L. plantarum GK81 was not different from the control by the addition of calcium. In the competition and exclusion experiment, the adhesion inhibition of S. Typhimurium by L. plantarum GK81 strain was much higher than the other strains. Moreover, the exclusion inhibition of S. Typhimurium by L. acidophilus GK20 was considerably high, although the inhibition activity of this strain was lower than L. plantarum GK81.

• Journal of Microbiology and Biotechnology
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• v.34 no.6
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• pp.1328-1339
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• 2024

Cadmium (Cd) is a prevalent environmental contaminant that poses a potential hazard to the health of both humans and animals. In this study, biosynthesized selenium-enriched Lactobacillus plantarum and selenium nanoparticles (SeNPs) were developed and evaluated for their protective effects against Cd-induced hepatic injury in mice through oral administration for 4 weeks. Cadmium exposure resulted in severe impairment of liver function, as evidenced by increased levels of serum markers of liver injury and, oxidative stress and significant damage to liver tissue, and a notable decrease in the diversity of the intestinal microbiota. Oral administration of Se-enriched L. plantarum (LS) reduced cadmium accumulation in the liver by 49.5% and, restored other cadmium-induced damage markers to normal levels. A comparison of the effects with those of L. plantarum (L) and SeNPs isolated from LS revealed that LS could more effectively alleviate hepatic oxidative stress and reduce the intrahepatic inflammatory responses of the liver, further protecting against cadmium-induced liver injury. These findings suggest that the development of LS may be effective at protecting the liver and intestinal tract from cadmium-induced damage.

• Journal of the East Asian Society of Dietary Life
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• v.13 no.5
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• pp.425-432
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• 2003

Effects of ethanol and/or some organic acid on the growth of some microorganism grown in Kimchi, Lactobacillus plantarum, Leuconostoc mesenteroides. Kluyveromyces marxianus, were identified and the cell injury was observed by measuring optical density at 260nm. When 0.0∼5.0% ethanol was added in the growth medium, the cell growth was inhibited depending on the concentration. Organic acids involving acetic, adipic and citric acid inhibited the growth of L. plantarum and Leu. mesenteroides, but K. marxianus, the yeast, was not at 0.1% of organic acid. When 2.0% of ethanol and 0.1% of organic acid were used, adipic acid was more effective on the growth inhibition. This inhibition of microbial growth seemed to be caused by the leakage of internal contents from microbes which were observed by the optical density at 260nm in the buffer supernatant. 5.0% of ethanol accelerated the optical density increase at 260nm in L. plantarum, Leu. mesenteroides and K. marxianus, but 2.0% of ethanol did not. 0.1% organic acid increased the absorbance of the supernatant in lactic bacteria, but not in yeast, K. marxianus. The measurement of absorbance at 260nm revealed that the cell injury increased when 2.0% of ethanol and/or 0.1% of organic acid. especially adipic acid were added.

• Korean Journal of Food Science and Technology
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• v.48 no.6
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• pp.548-554
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• 2016

Since some strains of kimchi lactobacilli can curdle milk, they can be used for making yogurt. However, the best Lactobacillus plantarum strains for curdling milk for yogurt are still unknown. In this study, we determined the best L. plantarum strains for curdling milk, and the physicochemical properties of yogurts made using different L. plantarum strains were examined. Three strains of L. plantarum useful for curdling milk were identified (YD2, YD9, YD12). The number of lactobacilli was lower in yogurts made with L. plantarum than in those made with control, and among the L. plantarum strains tested, YD12 had the highest bacterial counts. However, the microbial count reached $6.3{\times}10^8CFU/mL$ after 24-h fermentation in all yogurts. The pH of the yogurts decreased after 12-h fermentation, while the acidity increased. The low pH and high acidity decreased the viscosity in all the three types of yogurts, because the acids disturbed gel formation due to protein denaturation. Sensory evaluation revealed that the YD12 group showed a high percentage of completion similar to the control group. YD2 and YD9 showed a high sourness value and low sweetness value, whereas YD12 yielded optimal values for all the organoleptic characteristics. Therefore, YD12 would be a high quality bacterial strain for use as a yogurt starter culture.

• Journal of Life Science
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• v.29 no.1
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• pp.29-36
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• 2019

We investigated the fermentation conditions for extracts of leave/branches and sap from Korean Dendropanax morbifera (D. morbifera) using Lactobacillus plantarum (L. plantarum) ilchiwhangchil 1785 and L. plantarum ilchiwhangchil 2020. Log growth phase cultured L. plantarum ilchiwhangchil 1785 and L. plantarum ilchiwhangchil 2020 were used for fermentation. The pH and growth of the microorganisms in broth were monitored during the fermentation period. The results revealed that the optimum fermentation conditions for 20 wt% of leave/branches extracts and 1 wt% of sap extract was 2 days incubation at $37^{\circ}C$. The minimum inhibitory concentration (MIC) method and a disk diffusion assay were used to evaluate the antimicrobial activity of the fermented extracts of the leave/branches and sap against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. The antimicrobial activity increased in all three strains grown on the medium containing fermented extracts of the leave/branches and sap as compared with that of the strains grown on medium containing non fermented extracts. Furthermore, the antimicrobial activity increased in proportion to the contents of the fermented extracts. Our data suggest that fermented extracts of leave/branches and sap of D. morbifera have applications as natural bio functional materials, such as preservatives, cosmetic materials, and natural packaging materials.

• Journal of Veterinary Clinics
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• v.30 no.6
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• pp.459-463
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• 2013

A study investigated the effects of a mixture of Lactobacillus plantarum (L. plantarum) and Bacillus subtilis (B. subtilis) on diarrhea incidence, immune response, and fecal microflora counts in post-weaning piglets. One hundred 28-day-old piglets were randomly assigned to five treatment groups: negative control (NC), free of antibiotics; positive control (PC), 0.03% chlortetracycline; LB 1, a mixture of L. plantarum and B. subtilis (LB) 0.5 kg/ton feed; LB 2, LB 1.0 kg/ton feed; and LB 3, LB 2.0 kg/ton feed. Diarrhea scores for LB 2 and LB 3 from the 2nd week were significantly reduced compared to NC (P<0.05). In terms of the level of IgG and IFN-${\gamma}$, all treatment groups were significantly higher than NC (P<0.05), and the IgG level of LB 3 was significantly higher than that of PC (P<0.05). Furthermore, fecal lactic acid bacteria (LAB) counts for LB 2 and LB 3 were significantly higher than those of NC and PC (P<0.05). In addition, fecal Enterobacteriaceae (ENT) counts for PC, LB 2 and LB 3 were significantly lower than those of NC (P<0.05). Based on the results from this study, it was concluded that a combination of L. plantarum and B. subtilis strains could be used as potential alternatives to antibiotics to prevent diarrhea incidence in piglets.

• Food Science and Preservation
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• v.14 no.2
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• pp.188-193
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• 2007

The purpose of this study was to isolate lactic acid bacteria, useful in the fermentation industry from Hahyangju Nuruk. Five strains were isolated, and identified as Lactobacillus based on growth inhibition by 10% (v/v) alcohol at pH 4.0. Isolated strains were identified to species, and named Lactobacillus plantarum L-3, L. sakei L-10, and L. curvatus strains L-8, L-11, and L-12. Morphological characteristics, physiological data, carbohydrate fermentation patterns, and 16S rRNA sequence data, were all used to characterize the bacterial isolates. L. plantarum L-3 showed the highest lactic acid productivity of all isolates, but grew only poony in the presence of 10% (v/v) alcohol at pH 4.0. The other strains exhibited lower lactic acid productivity than did L. plantarum L-3 and did not grow in the presence of 10% (v/v) alcohol at pH 4.0. The optimal temperature and pH for lactic acid production were $30^{\circ}C$ and pH 6.0 7.0, respectively. The lactic acid productivity of L. plantarum L-3, L. sakei L-10 and the three L. curvatus strains L-8, L-11, and L-12 were (% v/v of culture supematant) 1.55, 1.0, 1.06, 1.0, and 0.99, respectively, at $30^{\circ}C$ and pH 6.0. While L. plantarum L-3 suffered growth inhibition in the presence of 10% (v/v) alcohol, growth of the other strains was inhibited at 8% (v/v) alcohol.