• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.362-368
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• 1997

As a preliminary study for the development of cancer-preventing functional food using Korean mistletoe, the cytotoxic effects of Korean mistletoe on between non-tumorigenic A3l cell and tumorigenic MSV cell derived from mouse 3T3 fibroblast cell line were investigated. While the raw extract, of which $ID_{50}$, value was $3.94\;{\mu}g/mL$, showed strong cytotoxic effect, its heat-treated extract was not cytotoxic up to $30\;{\mu}g/mL$. On the other hand, the heat-treated extract with law concentration showed an accelerative effect on the proliferation of non-tumorigenic A3l cell and an inhibitory effect on that of tumorigenic MSV cell. In addition, the influences of the addition of carbohydrates, such as galactose, lactose, glucose, mannose, fructose, sucrose and starch, to mistletoe extract were studied. There were not any significant changes with raw extract plus carbohydrate treatment, but the accelerative and inhibitory effects of heat-treated extract on each A3l and MSV cell were increased further by the treatment with sugars such as lactose, galactose, glucose, fructose. In order to investigate the changes of cytotoxicity of fermented Korean mistletoe according to fermentation periods, the raw and heat-treated extract were inoculated with Lactobacillus plantarum. During 1, 3, 5 and 7 fermentation days, the fermented raw mistletoe extract showed gradual accelerative effect on A31 cell proliferation without any changes of cytotoxicity on MSV cell. In case of the fermented heat-treated extract, however, the accelerative effect of heat-treated extract on A31 cell proliferation in early stage was disappeared during the fermentation.

• Journal of The Korean Society of Grassland and Forage Science
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• v.28 no.3
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• pp.255-264
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• 2008

This study was conducted to evaluate the effects of rumen protected choline on in vitro ruminal fermentation and milk production and its composition in Holstein cows. Experiments were done with three treatment groups, basal diet without any supplement (T1), basal diet+23g/d of mixture of choline and wheat shorts (T2) and basal diet + 25.56 g/d of rumen protected choline (T3). The in vitro ruminal pH and ammonia concentrations were similar for three treatments during all incubation periods except for the in vitro ruminal pH on 3 hr incubation and ammonia concentrations on 9 hr incubation. No significant difference was found in the concentrations of acetate and total-VFA. The propionate and butyrate concentrations were not affected by the rumen protected choline except on 6 hr incubation on which the propionate and butyrate concentrations were intermediate (8.98 mg/dl) and least (3.22 mg/dl), respectively. Higher milk yield and milk fat and lactose were resulted in the rumen protected choline. However, the rumen protected choline did not affect the milk protein, solids not fat, total solids, MUN, somatic cell count. It is concluded that the rumen protected choline can be effective materials to improve the milk production, milk fat and lactose without little change on in vitro ruminal fermentation.

• Journal of Microbiology and Biotechnology
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• v.9 no.1
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• pp.84-90
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• 1999

The growth of Bifidobacterium breve strain HP2 was completely inhibited by the addition of lactate higher than 4.0％ but not by the addition of acetate. Two kinds of lactate-tolerant mutants were isolated by the nitrosoguanidine treatment, enrichment on a liquid medium with 5％ lactate, and selection on agar plates with 5％ lactate. The mutants were not only able to grow in the presence of 5％ lactate but also improved in viable cell stability in the acidic pH range. In a pH-controlled fermentor, mutant N-1-5 grew at a rate slower than that of the wild type but its growth yield was higher. Notably, mutants were more halotolerant and more osmotolerant than the wild type and they were able to grow in the presence of 3％ NaCl or 25％ lactose at which the wild type entirely stopped the growth. The enzyme activities involved in the lactose metabolism in B. breve were measured to elucidate the biochemical basis for lactate tolerance. In the mutants, activities of several enzymes including phosphoglucomutase decreased compared to the wild-type, which may explain their lower growth rate. However, the activity of lactate dehydrogenase or its nature of inhibition by lactate was not altered.

• The Journal of Korean Society of Virology
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• v.27 no.2
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• pp.143-149
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• 1997

Most of the current licenced hepatitis B vaccines are being produced by recombinant DNA technology in large fermentation cultures of Saccharomyces cerevisiae of yeast cells which carry the gene coded for hepatitis B virus surface antigen. These vaccines are proved very effective clinically and the immunogenicity of vaccines could be maintained for a long time under refrigeration. To develope the stabilizer that could increase the stability of hepatitis B virus vaccine which could be stored for a long period at room temperature or higher conditions, glucose, lactose and sucrose solutions in phosphate buffered saline were added into hepatitis B vaccine respectively to make 2.5%, 5%, 7.5% and 10% final concentration in vaccines. These sugar-vaccine mixtures were stored at room temperature for one month, two months and three months respectively and then inoculated into ICR mice intramuscularly. On the fourteenth day after inoculation, mice were bled and sera were tested for the evaluation of efficacies of vaccines. The results showed that 5% glucose, 7.5% lactose and sucrose increased the stability of vaccines in some degree and this method could be applied for the production of other viral vaccines and bacterial vaccines.

• Korean Journal of Veterinary Research
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• v.34 no.1
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• pp.99-105
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• 1994

Clotridium bovis sp. nov, is described on the basis of 5 strains isolated from the feces of Holstein cattle. The isolate are gram-positive, motile, strict anaerobic spore forming rods. They differ from all the validly described related species of the genus Clostridium in carbohydrate fermentation pattern, G+C mol% and DNA homologies. Acid is produced from arabinose, xylose, glucose, mannose, fructose, galactose, sucrose, maltose, cellobiose, lactose, trehalose, melibiose, raffinose, inulin and salicin. Major end products in PYFG broth are large amounts of butyric acid and lactic acid, and trace amounts of acetic and succinic acids. The G+C mol% of DNA from the type strain is 26 mol%. The type strain of Clostridium bovis is Catt $66^T$ strain.

• The Journal of the Korean Society for Microbiology
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• v.8 no.1
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• pp.13-17
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• 1973

To understand the characteristics of 29 toxigenic strains of Corynebacterium diphtheriae isolated in Seoul area, type classification, biochemical properties and antibiotic susceptibility pattern to 9 kinds of antibiotics were investigated. The results obtained were summerized as follows; I. Among the 29 strains, gravis type was the overwhelming majority(24 strains), followed by intermedius type(3 strains) and mitis type(2 strains). II. Fermentation of glucose, maltose, lactose, trehalose and mannitol, nitrate reduction and urease were tested. All strains fermented glucose, but not sucrose, lactose, mannitol and trehalose. 9 strains fermented maltose and 20 strains did not. Nitrate was reduced by 28 strains but not by one strain. In urease test one strain showed positive, 28 strains negative. III. Antibiotic susceptibility test to penicillin G, chloramphenical, kanamycin, lincomycin, streptomycin, terramycin, erythromycin and gentamycin were carried out. The MIC of erythromycin(0.025 ${\mu}g/ml$ 26 strains and 0.05 ${\mu}g/ml$ 3 strains) was the lowest, followed by ampicillin, lincomycin and penicillin G. Streptomycin showed the highest MIC.

• Culinary science and hospitality research
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• v.12 no.2 s.29
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• pp.195-205
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• 2006

In this study, we investigated the quality characteristics of curd yogurt with different content of Rubus coreanus Miquel juice. Yogurt was fermented with three kinds of lactic acid bacteria(Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus casei). The changes of quality characteristics were investigated during fermentation and an acceptance test was performed after fermentation. The pH was decreased on the whole, and titratable acidity was gradually increased during fermentation. The number of viable cells was increased in case of yogurt with 1% to 4% Rubus coreanus Miquel juice, while it was inhibited in the sample with 6% and 7%. There was similar content in composition of protein, lactose, FFA, TS and NFS of curd yogurt after fermentation. Color value of curd yogurt with Rubus coreanus Miquel juice was higher in L(brightness), a(redness) and b(yellowness), compared with the control. Sensory attributes of color, odor, taste, after taste and overall acceptability of the curd yogurt with 3% Rubus coreanus Miquel juice showed highest preference among samples.

• Preventive Nutrition and Food Science
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• v.7 no.4
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• pp.397-404
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• 2002

Soybean curd residue (SCR) was fermented by lactic acid bacteria, Lactobacillus rhamnosus LS and Entercoccus faecium LL, isolated from SCR. The pH, titratable acidify and viable cell counts were determined from the fermented SCR to evaluate the lactic acid production and growth of lactic acid bacteria. Optimal amounts of pretense enzyme and glucose, and ideal fermentation time for SCR fermentation were estimated by response surface methodology (RSM). Raw SCR fermented by indigenous microorganisms had 0.78 % titratable acidity, The acid production in SCR fermented by L. rhamnosus LS was greatly enhanced by the addition of glucose and lactose. However only glucose increased acid production by Ent. faecium LL. The proof test of SCR fermentation demonstrated that similar results for titratable acidity, tyrosine content and viable cell counts to that predicted could be obtained by the at optimized fermentation conditions. In the presence of 0.029 % (w/w) pretense enzyme and 0.9% (w/w) glucose, the SCR fermented by Ent. faecium LL showed 1.07% (w/v) of titratable acidity, 1.02 mg% tyrosine content and 2$\times$10$^{9}$ (cfu/g) of viable cell counts. With the SCR fortified with 0.033% pretense enzyme and 1.7% glucose, L. rhamnosus LS showed 1.8% (w/v) of titratable acidity, 0.92 mg% of tyrosine content and 2$\times$10$^{9}$ (cfu/g) of viable cell counts.

• Korean journal of food and cookery science
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• v.12 no.2
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• pp.153-161
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• 1996

A curd yogurt was prepared from egg white powder (EWP) and casein added with sugars (glucose, fructose, lactose). The effects of sugar addition on acid production and growth of Lactobacillus were studied. The effects of sugar addition on sensory property and volatile aroma compounds were also studied. Acid production by L. acidophilus in EWP 2％ (W/V), casein 3％ (w/v) and sugar 0.5,1 or 2％ W/V) was lower than that of L. acidophilus in milk (control). Acid production in sample added with glucose or fructose of 1％ or 2% (W/V) was higher than that of 0.5% (W/V), while acid production in lactose added sample was not affected with the concentration of lactose. Number of viable cells of L. acidophilus at 24 hr in milk, glucose added sample, fructose added sample and lactose added sample was 3.6${\times}$10/Sup 9/, 5.6${\times}$10$\^$8/, 6.0${\times}$10$\^$8/,and 3.2${\times}$10$\^$7/, respectively. Through 30hr fermentation, acid production and number of viable cells of L. acidophilus in milk were higher than those of sugar added samples. Sensory property of fructose added sample was slightly better than that of milk yogurt (reference), while that of lactose added sample was significantly inferior. Though the composition of volatile aroma compounds was slightly different according to sample, gas chromatographic analysis detected acetone, ethanol, diacetyl and acetoin in samples fermented by L. acidophilus.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.4
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• pp.602-609
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• 2015

In this study, for modernization of Korean traditional fermented milk, Tarak was made using four kinds of commercial Makgeolli based on the ancient cookbook Suwoonjabbang. Samples of Tarak were periodically collected during 24 h of fermentation at $37^{\circ}C$. After fermentation, changes in pH, titration acidity, and viscosity were analyzed. Fermentation metabolites, including organic acids and free sugars, were analyzed by HPLC. Numbers of yeast and lactic acid bacteria during 24 h of fermentation were measured. The pH of Tarak significantly decreased (P<0.01), whereas its acidity significantly increased (P<0.01) during fermentation. The viscosity increased during 8~24 h of fermentation until curd was separated in Tarak. The level of ethanol increased from 0.37~0.52 mg/mL to 0.51~0.71 mg/mL during 24 h of fermentation. Lactic acid and lactose were the major organic acid and free sugar in Tarak, respectively. The number of lactic acid bacteria increased from 5.23~6.25 log CFU/mL to 9.87~10.41 log CFU/mL at the beginning during 24 h of fermentation. The number of yeast increased from 5.14~6.47 log CFU/mL to 6.99~7.73 at the beginning during 24 h of fermentation at $37^{\circ}C$. The major strains of Tarak were Pediococcus acidilactici, Lactobacillus fermentun, Lactobacillus curvatus, and Saccharomyces cerevisiae. Therefore, we concluded that Tarak was a fermented milk by both lactic acid bacteria and yeast, which was similar to koumiss or kefir.