• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.2
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• pp.306-312
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• 2013

The purpose of this study was to evaluate the physicochemical and sensory characteristics of white bread and added 2%, 4%, 6%, or 8% Hallabong powder. Dough pH of the control group was 5.65, and it decreased as increasing amounts of Hallabong powder were added. Also, total titratable acidity of dough significantly increased with increases in Hallabong powder. The fermentation power and dough expansion significantly increased with increasing incubation time; the control was highest at 98.67%. White bread pH, specific volume, and baking loss decreased significantly as with increased Hallabong powder content. The bread moisture content was not significantly different between samples, differing only from 40.61~41.83%. Water activity was 0.960 Aw in the 6% Hallabong powder mixture, which was the highest in samples. In color, lightness of crust significantly decreased with increased Hallabong powder content, whereas redness showed the reverse effect. Lightness of crumbs significantly decreased, with increased Hallabong powder content, whereas redness and yellowness showed the reverse effect. In texture, hardness and fracturability significantly increased, while resilience showed the reverse effect. In the sensory evaluation, citrus flavor, bitterness, astringency, and off-flavor significantly increased with increased Hallabong powder content, and the control sample showed the highest score in color, flavor, softness and overall acceptability. The 2% and 4% samples showed more than average scores. Based on these results, Hallabong powder could be considered a functional material. The optimum amount of Hallabong powder to add for baking bread would be 2~4%.

• Korean Journal of Agricultural Science
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• v.11 no.2
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• pp.322-327
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• 1984

As a basic studies for the laboratory scale production of alfalfa inoculum, Rhizobium meliloti M14 was characterized for its carbon and nitrogen sources, and some parameters for broth cultivation in a chemostat were studied by semi-continuous operation. The result s obtained were as follows. 1. Growth rate of the strain was increased by disaccharides than by monosaccharides tested, and pentoses resulted in poor growth than hexoses. Sugar alcohols including inositol supported the best growth among sugars. 2. Mannitol in the yeast-mannitol-broth was substituted by natural carbon sources such as malt extract or molasses. 3. Ten per cent of fresh yeast water appeared to supply enough amount of growth factor s for the strain, and the effect was equivalent to 0.24 percent of the commercial yeast extract powder. 4. Batch growth of the stain in a chemostat, New Brunswick Micro Ferm 28L, reached in the early stationary growth phase of $5{\sim}7{\times}10^9cells/ml$ after 36 hours of incubation. The culture at this stage was switched to semi-continuous cultivation, and the culture broth of four-fifth of the working volume was recovered every 24 hours when the maximal count was obtained.

• Radiation Oncology Journal
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• v.12 no.1
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• pp.17-25
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• 1994

We evaluated the effect of nicotinamide on cellular $O_{2}$ consumption and metabolic status i.e., adenylate phosphates and $NAD^{+}$in-vitro, and changes in blood flow in-vivo, to determine whether changes in cellular metabolism or increased oxygen availability, was responsible for increased tumor oxygenation. Thirty min, pre-incubation of cells with$\∼$4mM (= 500mg/kg) nicotinamide resulted in no change in cellular $O_{2}$ consumption. Similarly neither the adenylate Phosphates nor the cellular $NAD^{+}$levels were altered in the presence of $\∼$4mM nicontinamide. In-vivo, nicotinamide (500mg/kg) increased $O_{2}$ availability as estimated by changes in relative tumor blood flow (RBC flux). The changes in RBC flux measured by the laser Doppler method, were tumor volume dependent and increased from$\∼$35$ \% $ in$\∼$ 150$mm_{3}$tumors to$\∼$~75$ \% $ in$\∼$500$mm^{3}$ tumors. In conclusion, these observations indicate a reduction in local tissue $O_{2}$ consumption is not a mechanism of improved tumor oxygenation by nicotinamide in FSa II murine tumor model. The primary mechanism of increased $pO_{2}$ appears to be an increased local tumor blood flow.

• The Korean Journal of Mycology
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• v.40 no.3
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• pp.152-158
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• 2012

The lignocellulytic enzymes including a-amylase (EC 3.2.1.1), lignin peroxidase (EC 1.11.1.14), laccase (EC 1.10.3.2), xylanase (EC 3.2.1.8), ${\beta}$-xylosidase (EC 3.2.1.37), ${\beta}$-glucosidase (EC 3.2.1.21) and cellulase (EC 3.2.1.4) were extracted from spent mushroom compost (SMC) of Pleurotus eryngii. Different extraction buffers and conditions were tested for optimal recovery of the enzymes. The optimum extraction was shaking incubation (200 rpm) for 2 h at $4^{\circ}C$. ${\alpha}$-Amylase was extracted with the productivity range from 1.20 to 1.6 Unit/SMC g. Cellulase was recovered with the productivity range from 2.10 to 2.80 U/gf. ${\beta}$-glucosidase and ${\beta}$-xylosidase productivities showed lowest recovery producing 0.1 U/g and 0.02 U/g, respectively. The P. eryngii SMCs collected from three different mushroom farms showed different recovery on laccase and xylanse, cellulase. Furthermore, the water extracted SMC was compared to commercial enzymes for its industrial application in decolorization and cellulase activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.12
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• pp.1896-1905
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• 2014

The purpose of this study was to manufacture white bread by substituting bakery yeast with natural starter. The general composition of wild grape, was 81.22% moisture, 0.81% ash, 0.74% crude fat, 1.58% crude protein, and 15.65% carbohydrate contents. Fermented wild grape extract was made by culturing for 4 days at $25^{\circ}C$. Flour was added three times to fermented wild grape extract and incubated for 36 hours at $20^{\circ}C$ to manufacture sourdough. We investigated the quality characteristics of white bread with different amounts of fermented wild grape sourdough. The pH of dough decreased with increasing amounts of sourdough, whereas total titratable acidity of dough significantly increased. Fermentation power of dough expansion significantly increased with increasing incubation time, and control showed the highest value of 126.67%. White bread specific volume was highest in, 50% sourdough at 4.76 mL/g. Water content increased with increasing amounts of sourdough, whereas water activity was not significantly different between the samples. For texture, hardness of 50% sourdough was lowest at 19.23 g. In the sensory evaluation, color, flavor, softness and overall acceptability decreased with increasing amounts of sourdough. As a result, 50% sourdough can be considered as a baker's yeast substitute for making natural fermented bread.

• The Korean Journal of Mycology
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• v.34 no.2
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• pp.92-97
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• 2006

The liquid culture extract of Coriolus versicolor was prepared by directly boiling the whole culture broth 7 days after incubation in 12% citrus extract medium. After removal of mycelial debris through filtration, this extract was further extracted with equal volume of ethyl acetate (1 : 1, v/v). The ethyl acetate extracts showed significant antibacterial activities against Stapylococcus aureus CCARM3230 and Psudomonas aeruginosa CCARM2171, which are resistant to several antibiotics. The most active fraction was eluted from a silica gel column with a mixture of dichloromethane and methanol (9 : 1, v/v) and the purity of this active substance was confirmed by HPLC analysis. The results suggest that the purified active substance could be a good source for the development of a new antimicrobial agent, especially for the treatment of antibiotic resistant bacteria.

• Korean Journal of Veterinary Service
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• v.44 no.3
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• pp.149-155
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• 2021

In virucidal efficacy testing, the chemical inactivation cannot be determined for all viruses due to the difficulties or the inability to culture sufficiently or the risk of exposure to the viruses. Therefore, disinfectants against these viruses could be evaluated by different methods and surrogate viruses are used as alternative. In this study we developed a method for efficacy testing of veterinary disinfectants using one of the candidate surrogate viruses, bacteriophage MS2, as part of the research on the selection of surrogate viruses for efficiency of efficacy testing of veterinary disinfectants. This method is based on the Animal and Plant Quarantine Agency (APQA) guidelines for efficacy testing of veterinary disinfectants. Bacteriophage and disinfectant are reacted in suspension in accordance with the APQA guidelines and then a newly established double agar layer method is applied for the efficacy test. The double agar layer method is summarized as follows: 1) The bottom agar with 1.5% agar is boiled and cooled before poured into petri dishes at volume of 20 mL, and dried under biological safety cabinet. 2) The top agar with 0.7% agar is boiled and kept at 50℃ before E. coli culture was seeded. 3) The serially diluted bacteriophage MS2-disinfectant mixtures 0.05 mL and E. coli host 0.01 mL (OD₆₀₀ 0.2~0.3) are mixed with 5 mL of top agar and incubate them at 50℃ for 5 min for reaction. 4) The resulting mixture is poured over top of a bottom agar plate and rocked sufficiently to ensure that the top agar covers the entire surface of the bottom agar. 5) The double agar layer is then placed under biological safety cabinet to allow the agar layer to solidify and subsequently incubated at 37℃ for 24 hr. 6) Following incubation, the plates may be inspected for plaques and record results.

• Journal of the Korean Magnetics Society
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• v.4 no.1
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• pp.12-19
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• 1994

The crystallization behavior of the amorphous $Fe_{73.5}Cu_{1}Nb_{3}Si_{16.5}B_{6}$ alloy with isothermal annealing at $552^{\circ}C$ was studied by $M\"{o}ssbauer$ spectroscopy. The amorphous phase was revealed to coexist together with $Do_{3}-FeSi$ nanocrystalline and Cu-duster in annealed alloys by $M\"{o}ssbauer$ spectrum analysis. At the early stage of crystallization, Si content of FeSi is high due to the creation of Cu-cluster, and decreases with annealing until 60 minutes, which results in the increase in the mean hyperfine field of FeSi, and thereafter keeps constant. After 60 minutes, the decrease in the mean hyperfine field of the residual armrphous, in spite of a slight change in the volume fraction of the FeSi and the residual armrphous, is caused by the increase in the content of Nb and B in residual amorphous phase. Both directions of the hyperfine field, those of the FeSi and the residual amorphous, become randomly oriented in about 60 minutes. For FeSi and Cu-duster, the Avrami exponents are 0.51 and O.65, the activation energies are 2.35 eV and 2.44 eV, and the incubation times are 2.4 minutes and 0.8 minutes respectively. Earlier formation of Cu-duster than that of FeSi is coincidence with the fact that Cu atom promotes the nucleation of the FeSi.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.7
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• pp.914-920
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• 2008

In this study, hard roll breads were prepared with 3, 6, 9, 12, and 15% of concentrated sweet pumpkin powder (CSPP). The samples and a control were then compared in terms of quality characteristics, including pH, total titratable acidity, fermentation power of dough expansion, specific volume, baking loss, moisture content, color, textural characteristics, external and internal surface appearances, and sensory qualities of bread in order to determine the optimal ratio of CSPP in the formulation. As CSPP content increased, pH of dough, specific volume, baking loss, and lightness of bread decreased, while total titratable acidity of dough, pH, total titratable acidity, moisture content, and redness of bread increased. Fermentation power of dough expansion increased as incubation time increased. The CSPP samples had significantly higher yellowness, hardness, cohesiveness, gumminess, chewiness, and resilience than the control group. Adhesiveness was the highest at the 12% substitution level, while the lowest at the 6% level. Springiness increased with increasing CSPP content. In the sensory evaluation, as CSPP content increased, scores for color and consistency of crumb decreased, while scores for aroma of sweet pumpkin, sweetness, and delicious taste increased. Density of crumb pore were maximal with the 12% CSPP substitution. The CSPP samples had significantly higher uniformity of crumb pore and springiness of crumb than the control group. However, mouth-feel and overall acceptability showed the reverse effect, obtaining fairly good scores. In conclusion, the results indicate that substituting $6{\sim}9%$ CSPP to hard roll bread is optimal, providing good physiological properties as well as reasonably high overall acceptability.

• Applied Biological Chemistry
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• v.39 no.1
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• pp.54-59
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• 1996

Three strains of inhibitory lactic acid bacteria (No. 49, No. 61, No. 75) against Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escheirchia coli(ATCC33694) and Bacillus subtilis(ATCC6633) were isolated from kimchi, and then, identified to be Lactobacillus plantarum after examinations of their biological and physiological characteristics. To investigate a possible application of these three lactobacilli in milk fermentation industry, we made yogurts and then evaluated their ${\beta}-galactosidase$ activities at various; incubation time(from 24 hrs to 72 hrs). The result of experiment was that ${\beta}-galactosidase$ activities were reached maximum at 48 hrs and that reduced gradually with the lapse of time. And the ${\beta}-galactosidase$ activity of lactobacilli, and their viable cell counts at $37^{\circ}C$ for 2 hrs under various pH conditions were investigated. ${\beta}-galactosidase$ activities of 3 strains were reduced 50% at pH 3.5, but there were no remaining activities at pH 2.5, and pH 1.5, respectively. The frequency of the survival cell of lactobacilli in yogurt were $0.12{\sim}0.75%$ at pH 2.5, $$6.3{\times}10^{-5}{\sim}2.7{\times}10^{-3}% at pH 1.5, respectively, but there was no significant difference at pH 3.5. The values of original pH, titratable acidity as lactic acid, viscosity, and viable cells of yogurts were $4.08{\sim}4.30,\;1.05{\sim}1.25%,\;1,818{\sim}2,124\;cps\;and\;7.3{\times}10^8{\sim}3.0{\times}10^9\;cfu/m{\ell}$, respectively. To estimate buffer capacity of yogurt, the volume of 1.0 N HCl to 2 unit below original pH of yogurt($100\;m{\ell}$) was $11.98{\sim}13.02\;m{\ell}$ and the volume of 1.0N NaOH to 4 unit above original pH of yogurt($100\;m{\ell}$) was $10.82{\sim}12.86\;m{\ell}.