• Microbiology and Biotechnology Letters
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• v.44 no.1
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• pp.68-73
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• 2016

Lactic acid bacteria showing both protease activity and the capacity to produce casein phosphopeptide (CPP) were isolated from Korean kimchi, a traditional food made from fermented vegetables. Among the 450 strains of isolated lactic acid bacteria, the strain MG-379 showed high protease activity and the highest ability to produce CPP. Characterization results showed that MG-379 was gram-positive and measured $0.6-0.8{\mu}m$ in diameter. DNA sequencing of MG-379 and comparison with other sequences using BLAST revealed a 100% identity with the sequence of Enterococcus faecalis. However, MG-379 showed a higher CPP-producing ability than E. faecalis KCCM 40450. Accordingly, MG-379 was newly named as E. faecalis MG-379. Amount of free calcium liberated by CPPs was 2227.5 and 1151.6 mg/kg for E. faecalis MG-379 and E. faecalis KCCM (control), respectively.

• Korean Journal of Microbiology
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• v.47 no.4
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• pp.316-322
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• 2011

Lactobacillus sakei OPK2-59 isolated from kimchi was found to have ${\gamma}$-aminobutyric acid (GABA) producing ability and glutamate decarboxylase (GAD) activity. When the Lactobacillus sakei OPK2-59 was cultured in MRS broth with 59.13 mM and 177.40 mM monosodium glutamate (MSG), the optimum temperature range and pH for growth were $25-37^{\circ}C$ and pH 6.5, respectively. GABA conversion rates in MRS broth with 59.13 mM and 177.40 mM MSG were 99.58% and 31.00%, respectively at $25^{\circ}C$ and 48 h of cultivation. By using the cell free extract of Lactobacillus sakei OPK2-59, MSG was converted to GABA and the conversion rate was 78.51% at $30^{\circ}C$, pH 5. Conversion of MSG to GABA was enhanced by adding salts such as $CaCl_2$, $FeCl_3$, $MgCl_2$. These data suggest that the ability of Lactobacillus sakei OPK2-59 to produce GABA results from the activity of GAD in the cells and GABA conversion by the cell extract containing GAD can be enhanced by $CaCl_2$, $FeCl_3$, $MgCl_2$.

• Food Engineering Progress
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• v.13 no.4
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• pp.352-359
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• 2009

Lactic acid bacteria was isolated for the production of probiotic animal feed supplemented with garlic and its antimicrobial properties were investigated. A total of 112 strains of lactic acid bacteria which grew on the medium containing garlic extract were isolated from kimchi, jeotgal, and jangachi. Among them 14 strains were tested for acidand bile salt-resistance as well as antimicrobial activities against animal pathogenic bacteria such as Salmonella choleraesuis, Escherichia coli, Staphylococcus aureus, and Shigella flexneri. Of these strains, a strain P'GW50-2 from pickled scallion with most desirable properties was selected and identified as Lactobacillus plantarum TJ-LP-002. Antimicrobial activity of L. plantarum TJ-LP-002 showed relatively wide range of inhibition spectrum against Gram negative bacteria such as Aeromicrobium hydrophila, E. coli, Pseudomonas, Salmonella, Shigella, and some Gram positive bacteria such as Bacillus cereus, Staphylococcus aureus, Clostridium perfringens, and Propionibacterium.

• Food Science and Preservation
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• v.6 no.4
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• pp.514-520
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• 1999

Changes in pH, titratable acidity, CO$_2$production, reducing sugar, and lactic acid bacteria of fresh kimchi juice supplemented with combinations of 3 lactic acid bacteria and germanium(Ge)-132 or fructooligosaccharide(FO) during fermentation at 30$^{\circ}C$ were investigated to assess the potential for extending the shelf life and enhancing the functional properties in kimchi. In kimchi juice containing Ge-132, sample(I) (inoculated with a mixture of bacteriocin-producing SNF-13 strain and E. faecium) exhibited that the amounts of organic acid and evolved CO$_2$gas were lower than those of the other starter samples(II-IV). The growth of lactic acid bacteria naturally present in kimchi juice, particularly Lb. plantarum and Leu. mesentroides, may be inhibited due to competition of the isolated SNF-13 strain and E. faecium by Ge-132. During fermentation of kimchi juice containing FO sugar, the contents of organic acid and evolved CO$_2$gas On juice broth with 4 starters were predominantly higher than those of control and Ge-132 groups, and then the growth of lactic acid bacteria originated from kimchi ingredients was thought to be markedly accelerated. Our results indicated that functional properties like the extension of shelf life and increase of biological activity in kimchi were enhanced by adding Ge-132 and bacterium-producing lactic acid bacterium, which were resistant to organic acid and stimulated by Ge-132.

• Journal of Life Science
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• v.26 no.8
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• pp.970-975
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• 2016

Acne vulgaris is a common chronic skin disorder that affects millions of people. The pathogenesis of acne has been known to be closely associated with the bacterium Propionibacterium acnes. Here we investigated the anti-acne activity of Lactobacillus plantarum K-1 BR by observing the expressions of proinflammatory cytokines, TNF-α, IFN-γ and IL-8, of human keratinocytes. When we applied heat-killed P. acnes to HaCaT cells, the inflammatory cytokines were induced by two- to four-fold compared to the normal control. When the bacteriocin, purified from L. plantarum K-1 BR, was pretreated to the HaCaT cells, the expression levels of TNF-α and IFN-γ stimulated by P. acnes significantly decreased to 25% and 30% of the induced levels, respectively. The IL-8 levels also significantly decreased with the concentration dependent manner of the bacteriocin. These results suggest that the bacteriocin from L. plantarum K-1 BR could reduce the expression levels of inflammatory cytokines and thus may relieve inflammations caused by acne.

• Korean Journal of Food Science and Technology
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• v.46 no.2
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• pp.148-152
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• 2014

A mutant strain of Lactobacillus paracasei (ML-7) was derived by ultraviolet irradiation of the parent L. paracasei LS-2 strain, followed by colony selection on pH 3.5 MRS agar plates, on which L. paracasei LS-2 cannot grow. The L. paracasei ML-7 mutant strain produced an increased amount of organic acids compared to the L. paracasei LS-2 parent strain. Broiler chickens were randomly fed with one of three experimental diets: a basal diet as a control, and basal diets supplemented with 0.3% of the L. paracasei LS-2 and L. paracasei ML-7 strains. When concluding the study, the final body weights of the broilers fed with the supplemented basal diets were found to be significantly higher (1.9% for LS-2 and 6.2% for ML-7) than the control broiler group. Broilers fed with basal diet supplemented with the mutant L. paracasei ML-7 strain showed increased body weight and food intake, compared to broilers fed with the basal diet with or without the parent L. paracasei LS-2 strain.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.5
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• pp.612-620
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• 2012

This study was performed to investigate the 4-week repeated-dose toxicity of $Lactobacillus$ $plantarum$ AF1 ($Lb.$ $plantarum$ AF1), a lactic acid bacteria isolated from kimchi, in male and female rats. Sprague-Dawley male and female rats were divided into four groups, with 10 animals in each group. The test article was administered once daily by gavage to rats at dosage levels of 0, 0.5, 1.0, and 2.0 g/kg/day for 4-weeks. There were no test articlerelated deaths or abnormal clinical signs in either gender of rat during the observation period. Furthermore, no differences were found between the control and treatment groups in terms of body weight changes, food intake, and water consumptions. Hematological parameters, serum biochemical analysis, and any other findings also showed no significant or dose-dependent alterations. There were no alterations in organ weights upon administration of $Lb.$ $plantarum$ AF1. These results suggest that there were no adverse effects of oral application of $Lb.$ $plantarum$ AF1 up to a dosage level of 2.0 g/kg in both male and female rats.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.4
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• pp.600-607
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• 2013

This study was performed to investigate the repeated-dose toxicity of Leuconostoc citreum GR1 (Leuc. citreum GR1), a lactic acid bacterium isolated from kimchi, in male and female rats. Sprague-Dawley male and female rats were divided into four group (ten animals in each group) and Leuc. citreum GR1 was administered daily by gavage to rats at dosage levels of 0, 500, 1,000, or 2,000 mg/kg/day for four weeks. There were no bacterial-related deaths or abnormal clinical signs in either gender of rats during the observation period. Furthermore, no differences were found between the control and treatment groups in terms of body weight, food intake, and water consumption. Hematological parameters, serum biochemical analysis, and histopathological examination also showed insignificant dose-dependent alterations. There were also no alterations in organ weights upon administration of Leuc. citreum GR1 alone. These results suggest the oral application of Leuc. citreum GR1, up to a dosage level of 2,000 mg/kg, causes no adverse effects in both male and female rats.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.7
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• pp.1081-1087
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• 2014

This study investigated and compared the fermentation characteristics of intact kimchi and brined baechu cabbage and seasoning fermented separately. Fermentation characteristics of kimchi, brined baechu cabbage and seasoning, such as pH, acidity, microbial counts, and springiness were measured during the fermentation period (4 weeks at $4^{\circ}C$). Changes in pH, acidity, and microbial counts of the seasoning fermented separately were slower than those of brined baechu cabbage and kimchi itself. The fermentation characteristics of brined baechu cabbage were very similar to those of kimchi during the fermentation period. Additionally, we manufactured and fermented kimchi, after which baechu cabbage and seasoning were separated shortly before the measurements. Baechu cabbage and seasoning separated instantly from kimchi showed similar fermentation characteristics to their separately fermented counterparts. Changes in springiness of kimchi itself and brined baechu cabbage fermented separately were similar during the fermentation period. These results indicate that kimchi fermentation is affected by brined baechu cabbage more than seasoning.

• KSBB Journal
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• v.26 no.5
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• pp.374-380
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• 2011

Earlier in Korea Kimchi was made in every family and every province has own taste and specialties. These days almost of the Kimchis are manufactured. We collected variable Kimchis, which were made for private use and isolated microorganisms. Some interesting micobial cells were identified and studied for its application as food and drinks. One of them was identified as Lactobacillus sakei KJ123. This strain is known as producing interesting aromatic components during Sakei fermentation like Kimchi in variable conditions. We tried to develop a health beverage with fermentation process. The Cucurbita maxima has been known as a traditional healthy food and variable positive effects on the human body were already reported. In this study we tried to develop a production process for a healthy fermented drink on this substrate with strains originated from Kimchi. Many kinds of lacctobacilli species existed in the fermented food cannot survive in the acidic conditions like human stomach. So we selected resisting strains in this conditions. The survival rate of Lactobacillus sakei cells in the artificial gastric juice and bile acid and other physiological characteristics at the variable conditions have been tested. After fermentation process some sensory tests on the product with panels were tried.