• Microbiology and Biotechnology Letters
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• v.11 no.1
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• pp.1-4
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• 1983

In order to determine a proper amount of sodium pyrophosphate (SPP) which protect Lactobacilli from phage attack, Lactobacillus casei YIT-9018 was grown in $Ca^{＋＋}$ free Murata medium having various concentrations of SPP after infections with phage Jl at different multiplicities of infection (MOI). it was found that the level of SPP to inhibit phage activity depended upon the level of MOIs. When the bacteria were infected by less than 10$^{-1}$ of MOI, 0.15% of SPP was sufficient, while with 10$^{0}$ of MOI, 0.175% of SPP was needed to inhibit the lytic activity completely.

• KSBB Journal
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• v.11 no.3
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• pp.276-287
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• 1996

Batch suspension cultures of hybridoma cell were performed with various initial glutamine concentrations to investigate the effects of glutamine on cell growth and death, monoclonal antibody production, glucose and glutamine consumption, and the production of lactate and ammonium ion. An mathematical kinetic model was formulated to describe the kinetics of cell growth, the consumption of nutrients (glucose and glutamine), and the production of monoclonal antibody and waste metabolites (lactate and ammonium ion) based on experimental data. An equation for the specific growth rate was developed such that superimposed Monod equation in glucose and glutamine, with non-competitive type inhibition relations in ammonium ion and lactate. The inhibition constant for lactate was inversely proportional to the lactate concentration. The specific death rate was considered to be a function of glucose, glutamine, ammonium ion and lactate concentration.

• Journal of Life Science
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• v.14 no.3
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• pp.514-520
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• 2004

The antioxidative effects of fermented milk, mushroom extract and fermented milk containing its extract (Lentinus edodes, Ganoderna lucidum, and Pleurotus ostreatus) on the lipid peroxidation in the tissues of female Sprague-Dawley rats and on the DPPH ($\alpha,\alpha$' -diphenyl-$\beta$-picrylhydrazyl) radical donating ability were studied. The total concentrations of polyphenolic compound in Lentinus edodes, Ganoderma lucidum and Pleurotus ostreatus were 0.34, 0.20 and 0.34%, respectively. The DPPH donating abilities of mushroom extract, fermented milk, fermented milk containing its extract and BHT (butylated hydorxytoluene) as standard were 33.9, 34.9, 51.9 and 95.6%, respectively. Experimental diet groups were divided into five groups: the normal diet (ND), the cholesterol diet (CD), and cholesterol + fermented milk diet (CDFM), cholesterol + mushroom extract diet (CDME) and cholesterol + fermented milk containing mushroom extract diet (CDFMME). The concentrations of lipid peroxide in liver and its microsome were significantly lower in both CDFM and CDFMME groups than in the other groups. The kidney concentration of lipid peroxide was significantly higher in the CD group than in the ND group, but this rise were significantly decreased in the CDFM and CDFMME groups. Meanwhile, the concentrations of heart and spleen and their fractions were not significantly different among dietary groups. This study was suggested that the fermented milk diet containing mushroom extract effectively reduced the lipid peroxidation in liver and kidney of cholesterol-fed female rats.

• The Korean Journal of Food And Nutrition
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• v.28 no.6
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• pp.956-964
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• 2015

Probiotics is known improve the microenvironment of colon; however, the metagenomic DNA study of its lactic acid bacteria in constipation induced by loperamide is not clearly understood. In the present study, we investigated the reduction of the lactic acid bacteria in case of constipation, in normal and loperamide-induced rat. Lactic acid powder (lactic acid bacteria 19) was prepared from Chong Kun Dang Pharmaceutical Corporation. After 2 weeks of oral administration, the group treated with the higher concentration of lactic acid bacteria ($10^9CFU/mL$ per kg of body weight) following loperamide treatment was the most effective in increasing number, weight, and water content of feces. A similar but significant increase was found in the group treated with lower concentration of lactic acid bacteria ($10^7CFU/mL$ per kg of body weight) after loperamide treatment. The concentrations of acetic acid and propionic acid in feces in the loperamide-induced rat with high concentration lactic acid, were significantly higher than that of others. Furthermore, gastrointestinal transit ratio as well as the length and area of intestinal mucosa were significantly increased after treatment with lactic acid bacteria in loperamide-induced rat. Metagenomics DNA analysis indicated that the microorganism homology in cecum was similar between the groups of normal (NOR) and HIG. Our results show that lactic acid bacteria were effective in improving the constipation.

• Microbiology and Biotechnology Letters
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• v.10 no.4
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• pp.253-258
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• 1982

Lactobacillus casei YIT 9018 was infected with phage J1 and subjected to grow in $Ca^{＋＋}$ -free MRT (spell out) medium under the presence of four different types of phosphates, sodium-metaphosphate,-pyrophos-phate,-dibasic phosphate, and potassium-phosphate. Among the phosphates tested, sodium pyrophosphate showed sufficient inhibition on the lytic activity of the phage at 0.1% level whereas other phosphate needed more than 0.2% for the same effect. When the concentration of sodium pyrophosphate increased to 0.17%, the bacteria could be protected from lysis until the second succeeding transfer.

• The Journal of the Korea Contents Association
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• v.22 no.9
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• pp.583-591
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• 2022

The purpose of this study was to determine the incidence of dental erosion according to the type of lactic acid bacteria fermented oil and to identify a method for preventing dental erosion. For the lactic acid bacteria fermented milk, liquid fermented milk, condense-stirred type fermented milk, and condense-drink type fermented milk were used, and bovine tooth specimens used in the experiment were used. As a method to prevent dental erosion, the method of adding calcium to the lactic acid bacteria fermented milk, the method of applying high and low concentrations of fluoride to the teeth before exposure to the lactic acid bacteria fermented milk, and the method of applying these two methods together were measured to measure the preventive effect of dental erosion. As a result of immersing the specimen in the experimental beverage, the surface hardness of liquid fermented milk decreased the most. When comparing the difference in surface hardness before and after prophylaxis care, the Ca 2% group and the NaF 0.05%+Ca 0.5% group showed no significant difference from the negative control group, confirming that it is an effective method for preventing dental erosion. However, considering the change in taste and the stability of ingredients, a method of adding calcium at a low concentration rather than adding a high concentration of calcium is proposed. Therefore, it is recommended to use low-concentration calcium and low-concentration fluoride together to recognize the possibility of dental erosion when ingesting lactic acid bacteria and to prevent dental erosion caused by it.

• KSBB Journal
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• v.25 no.3
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• pp.244-250
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• 2010

This study characterized the anti-Helicobactor pylori activity of Xanthium strumarium L. extract obtained by lactic acid fermentation. The growth of the Lactobacillus strains was typically robust upon lactic acid production in monocultures containing Xanthium strumarium L. extract. Lactic acid fermentation in mixed cultures of Lactobacillus brevis KCTC 3498 and Lactobacillus casei KCTC 3109 produced higher of anti- H. pylori activity than monocultures. Concerning antioxidant activity of fermented extracts, total polyphenol contents were the highest in co-cultures of Lactobacillus brevis KCTC 3498 and Lactobacillus helveticus KCTC 3545. Electron donating ability using diphenyl picryl hydrazyl (DPPH) showed 70% scavenging in Lactobacillus casei KCTC 3109.

• Applied Biological Chemistry
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• v.27 no.1
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• pp.7-13
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• 1984

The effects of various nutrients added to soy milk on the growth of Lactobacillus acidophilus were investigated. Soy milk was prepared from defatted soy flour and various nutrients such as sugars, growth stimulating agents, amino acid and milk by-products. The growth curve obtained from the experiment suggested that the log phase ended after 12hr. Glucose and fructose greatly enhanced the acid production by L. acidophilus. The optimum concentration of these two sugars in the media was approximately 3% each. Among the tested growth stimulating agents, yeast extract stimulated the acid production by L. acidophilus, and the optimum concentration of this additive was approximately 0.5%. L-methionine reduced the acid production by L. acidophilus. Whey powder and skim mills powder did not significantly stimulated the growth and acid production by L. acidophilus. Concentration of protein in soy milk did not affect the growth and acid production by L. acidophilus.

• Korean Journal of Food Science and Technology
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• v.50 no.4
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• pp.391-399
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• 2018

Bioconversion and fermentation of onion extract by lactic acid bacteria were carried out to enhance the bioavailability of quercetin through the increase of quercetin recovery and aglycone formation. Lactobacillus casei, L. plantarum, and Kluyveromyces lactis were selected as the optimum strains for bioconversion. The environmental conditions to maximize the conversion ratio between glycoconjugate and quercetin aglycone have been evaluated. The concentrations of quercetin after fermentation of onion slurry by K. lactis and L. casei increased to 260% and 318%, respectively; however, the quercetin concentrations decreased after 48 hours of fermentation. Additionally, the quercetin hexose concentration increased to almost 141%. Controlling the initial pH of the onion juice increased the lactic acid production by L. casei and L. plantarum by more than two-fold. Meanwhile, the concentration of quercetin hexose decreased rapidly with the increased production of aglycones. The scale-up experiments showed the same fermentation efficiency; however, thermal sterilization reduced the quercetin glycone concentrations drastically.

• Restorative Dentistry and Endodontics
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• v.32 no.1
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• pp.47-60
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• 2007

The purpose of this study is to compare and to evaluate the effect of pH and lactic acid concentration on the progression of artificial root caries lesion using polarizing microscope, and to evaluate the morphological changes of hydroxyapatite crystals of the demineralized area and to investigate the process of demineralization using scanning electron microscope. Artificial root caries lesion was created by dividing specimens into 3 pH groups (pH 4.3, 5.0, 5.5), and each pH group was divided into 3 lactic acid concentration groups (25 mM, 50 mM, 100 mM). Each group was immersed in acid buffer solution for 5 days and examined. The results were as follows : 1. Under polarized microscope, the depth of lesion was more effected by the lactic acid concentration rather than the pH. 2. Under scanning electron microscope, dissolution of hydroxyapatite crystals were increased as the lactic acid concentration increased and the pH decreased. 3. Demineralized hydroxyapatite crystals showed peripheral dissolution and decreased size and number within cluster of hydroxyapatite crystals and widening of intercluster and intercrystal spaces as the pH decreased and the lactic acid concentration increased. 4. Under scanning electron microscope evaluation of the surface zone, clusters of hydroxyapatite crystals were dissolved, and dissolution and reattachment of crystals on the surface of collagen fibrils were observed as the lactic acid concentration increased. 5. Under scanning electron microscope, demineralizatlon of dentin occurred not only independently but also with remineralization simultaneously. In conclusion, the study showed that pH and lactic acid concentration influenced the rate of progression of the lesion in artificial root caries. Demineralization process was progressed from the surface of the cluster of hydroxyapatite crystals and the morphology of hydroxyapatite crystals changed from round or elliptical shape into irregular shape as time elapsed.