• Food Science of Animal Resources
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• v.33 no.3
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• pp.335-340
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• 2013

This study screened for radio-resistant strains lactic acid bacteria (LAB) by evaluating their capability to survive exposure to ionizing radiation. Ten strains of LAB - Lactobacillus bulgaricus, Lactobacillus paracasei, Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus plantarum, Lactobacillus delbruekii, Lactococcus lactis, Streptococcus thermophilus, Bifidobacterium breve, and Pediocuccos pentosaceus - were selected and subcultuted twice. The LAB was then further cultured for 3 d at $37^{\circ}C$ to reach 7-10 Log colony-forming units (CFU)/mL prior to irradiation and immediately exposed to gamma rays or electron beams with absorbed doses of 0, 1, 2, 3, 4, 5, 6, 8, and 10 kGy. Gamma irradiation gradually decreased the number of the tested viable LAB, and the effect was irradiation dose dependent. A similar effect was found in electron beam-irradiated LAB. Radiation sensitivity of LAB was calculated as $D_{10}$ values, which ranged from 0.26 kGy to 0.9 kGy and 0.5 kGy to 1.44 kGy with exposure to gamma and electron beam irradiation, respectively, in all tested LAB. L. acidophilus was the most resistant to gamma and electron beam irradiation, with $D_{10}$ values of 0.9 kGy and 1.44 kGy, respectively. These results suggest that L. acidophilus might be suitable for the preparation of probiotics as direct-fed microbes for astronauts in extreme space environments.

• Journal of Dairy Science and Biotechnology
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• v.33 no.2
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• pp.93-102
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• 2015

The aim of this study was to investigate the physiological characteristics and immunomodulatory activity of Lactobacillus fermentum 450 isolated from raw milk. L. fermentum 450 showed optimum growth at $40^{\circ}C$ and exhibited immunomodulatory effects on $interleukin-1{\alpha}$, tumor necrosis $factor-{\alpha}$, and nitrous oxide at concentrations of >2,500 pg/mL, >2,000 pg/mL, and $11.55{\pm}2.95{\mu}M$, respectively. Of the 16 antibiotics tested, L. fermentum 450 exhibited the highest sensitivity to rifampicin, followed by penicillin-G, and the highest resistance to kanamycin, followed by neomycin and polymyxin B. The strain showed high acid phosphatase activity and was comparatively tolerant to bile juice and acid. Moreover, the strain displayed high resistance to Salmonella Typhimurium (63.86%). These results demonstrate that L. fermentum 450 has potential for use as a probiotic with immunomodulatory activity.

• KSBB Journal
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• v.20 no.3
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• pp.228-232
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• 2005

In this study, Artemisia mongolica fischer extract was examined for its possible differential inhibitory activity against pathogenic bacteria including Staphylococcus aureus and Lactobacillus spp. isolated from women's vagina. First, seven lactobacillus spp. were selected based on their in vitro high anti-staphylococcal activity. Various samples extracted using different concentrations of organic solvents (acetone, ethanol, methanol) were examined for optimal anti-staphylococal activity. When the Artemisia extract obtained using $100\%$ solvents was added to the cell suspension at $17\%$ (vol/vol), Lactobacillus sp. KLB 224 maintained its viability for 48 hr, whereas S. aureus was completely inactivated showing differential antimicrobial activity of the extract. Using scanning electron microscopy the effect of the extract on the cell morphology was observed: S. aureus showed markedly distorted cell morphology while Lactobacillus sp. KLB 224 appeared to remain intact.

• Korean Journal of Food Science and Technology
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• v.11 no.3
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• pp.200-205
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• 1979

Effects of monosodium phosphate, disodium phosphate, trisodium phosphate, ${\alpha}-polygel$, sodium ultrametaphosphate and sodium tripolyphosphate on the growth of bacteria, pH and acidity in single culture of Lactobacillus bulgaricus and mixed-culture of Lactobacillus bulgaricus and Streptococcus thermophilus were investigated. Phosphates exerted definite effect in enhancing the growth of the bacteria and acidity of the fermented milk. For the single-culture of Lactobacillus bulgaricus monosodium phosphate and sodium tripolyphosphate were most effective in terms of bacterial growth and acidity, whereas for the mixed-culture of Lactobacillus bulgaricus and Streptococcus thermophilus monosodium phosphate and disodium phosphate showed the best results. In the presence of the phosphates, particularly of trisodium phosphate, the decrease of viable count of bacteria in fermented milk during storage was reduced significantly. The stability of the fermented milk prepared with the mixed-culture of Lactobacillus bulgaricus and Streptococcus thermophilus was improved by the addition of phosphates, particularly of monosodium phosphate.

• Korean Journal of Microbiology
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• v.33 no.4
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• pp.247-251
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• 1997

Effects of amino acids on the lactic acid bacteria in kimchi were studied. 73 different lactic acid bacteria have been isolated during the kimchi fermentation at $15^{\circ}C$. Among these bacteria, dextran formers were occupied by 69.9%, of which Leuconostoc and Lactobacillus were 4.1% and 65.8%, respectively. All isolates didn't grow in a medium added with 500 ppm of tyrosine, whereas such an inhibition was not exhibited in kimchi with the same concentration of tyrosine. In kimchi added with tyrosine the lactic acid bacteria were less diverse than in the natural kimchi but the ratio of dextran formers were similar. As contrasted with natural kimchi, Leuconostoc was rather increased up to 41.4% and Lactobacillus was decreased down to 29.3%. Dominant species in each genus were Leu. mesenteroides and Lac. minor. Thus it is believed that tyrosine had inhibition effect for the growth of most Lactobacillus in kimchi.

• Korean Journal of Organic Agriculture
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• v.10 no.4
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• pp.61-67
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• 2002

The effect of the Penicillium sp. PS-113 with high phosphate solubilizing activity and Lactobacillus sp. was studied on cucumber growing test in green house. Inoculation of Pemicillium sp. Ps113 $5.0{\times}10^6$cfu/ml and Lactobacillus sp. $6{\times}10^6$cfu/ml were longer than control about 3cm length of cucumber. The average weight was also increased 89.2g more than control. Total product of cucumber was 10,681.7g and it was increased 4517.3g as compared to control. Thus, Inoculations of high phosphate solubilizing microorganism increased in productivity on cucumber.

• Korean Journal of Microbiology
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• v.55 no.3
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• pp.258-267
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• 2019

The purpose of this study was to investigate the effect of lactic acid bacteria (LAB) on the growth and biogenic amines (BA) formation of Enterobacter aerogenes CIH05 in skim milk and soymilk. Lactobacillus acidophilus GK20, Lactobacillus paracasei GK74, and Lactobacillus plantarum GK81 isolated from mustard kimchi did not produce BA in the decarboxylation broth. L. paracasei GK74 exhibited the highest cell viability and antimicrobial compounds producing ability in fermented skim milk and soymilk samples, while the lowest producer was L. plantarum GK81. The production yield of lactic acid, hydrogen peroxide, and bacteriocin was dependent on the species of Lactobacillus and the type of culture medium. As LAB the number of viable cells of E. aerogenes CIH05 were higher in skim milk than in soymilk. When mixed culture with L. acidophilus GK20 and L. paracasei GK74 and treated with bacteriocin solution (300 AU/ml) obtained from these strains in milk media, the cell growth and cadaverine and histamine contents of E. aerogenes CIH05 were significantly (P < 0.05) lower than the respective values in control sample.

• Food Science of Animal Resources
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• v.25 no.4
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• pp.483-493
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• 2005

This experiment was carried out to examine the fermentation properties of yogurt prepared with bovine milk and soybean milk at the mixed ratios of 3:1, 2:1, 1:1, 1:2 and 1:3. The effect of bovine milk and soybean milk on promoting the fermentation was higher un pH was $3.75\~4.16$ when Lactobacillus salivarius ssp. salivarius CNU27, lactic culture 1(Lactobacillus delbrueckii ssp. bulgaricus(LB12)), Streptococcus salivarius ssp. thermophilus (ST36) and Lactobacillus acidophilus KCTC3150 were used. Titratable acidity was the highest when lactic culture 1[Lactobacillus delbrueckii ssp. bulgaricus(LB12), Streptococcus salivarius ssp. thermophilus(ST36)] was mea and the mixed ratio of bovine milk and soybean milk was 2:1. The average viable counts of lactic acid bacteria was the highest level of $2.17\times10^9$ cfu/ml when Lactobacillus salivarius ssp. salivarius CNU27 was used, and the mixed ratio of bovine milk and soybean milk was 1:3. the highest lactic acid production was 412.52mM when lactic culture 1[Lactobacillus delbrueckii ssp. bulgaricus (LB12), Streptococcus salivarius ssp. thermophilus (ST36)] was used, and the mixed ratio of bovine milk and soybean milk was 1:1. The production of acetic acid was the highest and the concentration was 394.01mM when lactic culture 2(Bifidobacterium longum, Lactobacillus acidophilus, Streptococcus salivarius ssp. thermophilus) was used and the mixed ratio of bovine milk and soy bean milk was 3:1. Tn the carbohydrate hydrolysis, stachyose was hydrolyzed $53.92\%$ as compared with the control when Lactobacillus salivarius subsp salivarius CNU27 was used, and the mixed ratio of bovine milk and soy bean milk was 1:3. The highest viscosity of yogurt was $1,300\~1,660$ cP when the mixed ratio of bovine milk and soybean milk was 1:3. The overall acceptability, $4.17\pm0.69$, was the highest when Lactobacillus acidophilus KCTC3150 was used and when the mixed ratio of bovine milk and soybean milk was 2:1.

• Proceedings of the Membrane Society of Korea Conference
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• 2001.11a
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• pp.146-148
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• 2001

• Food Science and Industry
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• v.47 no.4
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• pp.8-13
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• 2014