• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1236-1242
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• 1998

Korean Lentinus edodes SR-1 was cultured to multiply the mycelia in the complete broth medium (C/N=13.1) for mushroom, and protein-bound polysaccharides were extracted from the cultured broth containing mycelia (The whole cultured broth was used to increase the yields: 80% of protein-bound polysaccharides were existed at the cell wall of mycelia and 20% of those were secreted extracellularily in this culture). Protein-bound polysaccharides in the cultured broth containing mycelia were extracted by using three different methods: 1) Extraction with hot water, 2) Disintegration of cell wall by glass bead mill treatment before extraction with hot water, and 3) Cellulase treatment before extraction with hot water. The highest yield was obtained (930 mg polysaccharides/100 mL culture broth) when protein-bound polysaccharides were extracted with 2) method. The extracted crude protein-bound polysaccharides were purified using protease, DEAE-cellulose and Sephadex G-100. The growth inhibition activity for $P_{388}$, mouse leukemic cell, increased (53.7, 62.2, 93.7% and 97.4%) as the purification level increased. Protein-bound polysaccharides contained 46.1% of polysaccharides, 7.3% of protein, and trace amounts of minerals. Polysaccharides contained glucose, galactose, xylose and mannose. The content of proline and glycine were high, however, methionine and leucine were not found. The major minerals were Na, K, Zn, and Ca.

• Food Science and Preservation
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• v.23 no.6
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• pp.848-858
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• 2016

This study was conducted to determine the $F_0$-values of a retort machine at different locations and to evaluate the effects of these $F_0$-values on various quality characteristics of retorted Samgyetang samples. Samples were divided into three groups based on $F_0$-values-T1, 10~20; T2, 20~30; T3, >30. Mineral content in Samgyetang broth and breast meat mostly increased with increasing $F_0$-values. In general, the free amino acid values, hardness, and springiness, except for bone springiness, of Samgyetang decreased significantly at higher $F_0$-values. Protein content of meat and broth of the treated samples were significantly lower than that of the control. An increase in the digestion rate of meat and porridge, as well as the turbidity of the broth was observed in most of the treated samples with increasing $F_0$-values. With increasing $F_0$-values, the $L^*$ and $b^*$ values of meat and the $b^*$ values of broth tended to increase, while the $a^*$ value of broth increased significantly. Electronic nose analysis revealed different flavor patterns for samples treated at different $F_0$-values. For sensory traits, samples treated with higher $F_0$-values tended to receive lower evaluations. Particularly, the color and texture of T3 samples were lower than those of T1 and T2 samples. In conclusion, to improve the quality of Samgyetang, the efficiency and optimization of retort machines as well as the standardization of sterilization techniques are needed.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.1
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• pp.76-83
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• 2002

The purpose of study was to determine the effectiveness of crude IgY to S. mutans in preventing the acid production and the demineralization of primary tooth enamel in vitro. The acid production by S. mutans in Todd Hewitt broth with and without 5% sucrose was inhibited by 2.5% crude IgY, and as the concentration of crude IgY increased from 2.5% to 17.5%, the pH drop of the media after incubation continued to decrease. There were high positive correlations between the concentration of crude IgY and the pH of media in the late incubation period. The inhibition rate of demineralization of primary tooth enamel by S. mutans was determined by measuring the surface microhardness after incubation in 5% sucrose Todd Hewitt broth for 12 hours. The inhibition rate was 32.28% in 2.5% IgY, 42.28% in 7.5% IgY, 64.06% in 12.5% IgY, and 92.79% in 17.5% IgY. There was high positive correlation between the concentration of crude IgY and the surface microhardness of enamel after demineralization These results suggest that it would be possible to prevent dental caries through passive immunization using crude IgY.

• Journal of Life Science
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• v.17 no.6 s.86
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• pp.816-821
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• 2007

This study was carried out to investigate the whitening effect of mycelial culture broth of P. japonica in the mulberry leaf extract. The culture broth inhibited melanin synthesis in vitro in the concentration dependent manner of 10 to 50%. The mulberry leaf extract itself has a cytotoxicity to the mouse melanoma cell, B16BL6 with the value of IC$_{50}$ of 7% concentration. But the culture broth of P. japonica in the mulberry leaf extract did not show any cytotoxicity up to 50%. Therefore, we concluded the mycelial culture broth of P. japonica in the extract of mulberry leaf can be used as a whitening cosmetic resource.

• Journal of Microbiology and Biotechnology
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• v.29 no.10
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• pp.1495-1505
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• 2019

The Burkholderia cepacia complex (BCC) is capable of remaining viable in low-nutrient environments and harsh conditions, posing a contamination risk in non-sterile pharmaceutical products as well as a challenge for detection. To develop optimal recovery methods to detect BCC, three oligotrophic media were evaluated and compared with nutrient media for the recovery of BCC from autoclaved distilled water or antiseptic solutions. Serial dilutions ($10^{-1}$ to $10^{-12}CFU/ml$) of 20 BCC strains were inoculated into autoclaved distilled water and stored at $6^{\circ}C$, $23^{\circ}C$ and $42^{\circ}C$ for 42 days. Six suspensions of Burkholderia cenocepacia were used to inoculate aqueous solutions containing $5{\mu}g/ml$ and $50{\mu}g/ml$ chlorhexidine gluconate (CHX) and $10{\mu}g/ml$ benzalkonium chloride (BZK), and stored at $23^{\circ}C$ for a further 199 days. Nutrient media such as Tryptic Soy Agar (TSA) or Tryptic Soy Broth (TSB), oligotrophic media (1/10 strength TSA or TSB, Reasoner's $2^{nd}$ Agar [R2A] or Reasoner's $2^{nd}$ Broth [R2AB], and 1/3 strength R2A or R2AB) were compared by inoculating these media with BCC from autoclaved distilled water and from antiseptic samples. The recovery of BCC in water or antiseptics was higher in culture broth than on solid media. Oligotrophic medium showed a higher recovery efficiency than TSA or TSB for the detection of 20 BCC samples. Results from multiple comparisons allowed us to directly identify significant differences between TSA or TSB and oligotrophic media. An oligotrophic medium pre-enrichment resuscitation step is offered for the United States Pharmacopeia (USP) proposed compendial test method for BCC detection.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.2
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• pp.185-191
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• 2000

The water-soluble glucan produced by Lactococcus lactis 1370 affects the formation of dental plaque by Streptococcus mutans. In this study the factors affecting the formation of water-soluble glucan were assessed as the optical density of culture supernatant of Lactococcus lactis 1370 in the spectrophotometer. 1. The optical density of culture supernatant was high when Lactococcus lactis 1370 was cultured in M17 broth with 5% sucrose, while being low in culture supernatant of Streptococcus mutans. 2. The optical density of culture supernatant was higher when Lactococcus lactis 1370 was cultured in M17 broth with 10% sucrose than when being cultured without sucrose (p<0.05), and was higher at pH 7 than pH 5 (p<0.05). 3. The optical density of culture supernatant was the highest at $37^{\circ}C$ among $32^{\circ}C,\;37^{\circ}C\;and\;42^{\circ}C$, and was higher in the anaerobic incubator than in the aerobic incubator (p<0.05). 4. The optical density of culture supernatant was the highest in the media containing 1.0mM $CaCl_2$ (p<0.05), 2.5mM KCl (p<0.05), and 1.6mM $MgCl_2$. 5. When Streptococcus mutans was cultured in the media containing a quarter culture supernatant of Lactococcus lactis 1370 grown in M17 broth, the mean weight of produced artificial plaque was 103.0mg on the wire, whereas being significantly reduced to 5.6mg in the media containing a quarter culture supernatant of Lactococcus lactis 1370 grown in M17 broth containing 5% sucrose (p<0.05). These results indicate that the water-soluble glucan is more formed by Lactococcus lactis 1370 in the media containing sucrose or under the adequate conditions for the growth of bacteria, and inhibits the formation of artificial plaque by Streptococcus mutans.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1999.10a
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• pp.5-5
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• 1999

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.2
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• pp.141-145
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• 2000

Entomopathogenic nematodes are being used for insect control. We purified a toxin secreted by the insect-pathogenic bacterium, Xenorhadbus nematophilus, which lives in the gut of entomopathogenic nematodes. Culture broth of X. nematophilus was separated by centrifugation and concentrated by ultration. The concentrated culture broth was applied to a DEAE Sephadex A-50 column, and proteins were eluted stepwise with increasing concentrations of KCI. Fractions column. The molecty weight of purified toxin was39 kDa on SDS-PAGE, and Fourier tranformed infrared (FTIR) spectroscopy indicated that this toxin could be a new protein exhiting the charactristics of C=O stretching peak near 1650cm-1.

• Journal of Microbiology and Biotechnology
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• v.8 no.5
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• pp.536-539
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• 1998

The anti-complementary activity (immuno-stimulating activity) was tested for the exo-polymers (extra-cellular polymer) produced from submerged mycelial cultures of 21 types of higher fungi. Anti-complementary activity of the exo-polymer from Cordyceps militaris showed the highest (69.0%) followed by Pleurotus ostreatus (63.7%) and Trametes suaveolens (61.4%). The mycelial growth rate and biomass doubling time of C. militaris in a 5 I air-lift fermenter were 0.0255 $h^{-1}$ and 27.2 h, respectively. The yield of the exo-polymer produced from the culture broth of C. militaris was 2.95 mg of dry weight/ml of culture broth. Sugar and amino acid compositions of this exo-polymer were analyzed.

• Food Science and Biotechnology
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• v.14 no.4
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• pp.518-522
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• 2005

Yogurt containing high ${\gamma}$-aminobutyric acid (GABA) was developed using lactic acid bacteria and germinated brown rice. Lactobacillus acidophilus, L. plantarum, and L. brevis OPY-1 strains were inoculated into Lactobacillus MRS broth for use as yogurt starter. After treatment with 5% monosodium glutamate in MRS broth, L. brevis OPY-1 strain isolated from Kimchi produced GABA concentration of 8,003.28 nmol/mL. Starter was inoculated into fermentation substrate mixture containing germinated brown rice extract and blend of powdered whole milk and skim milk. Samples were incubated, and viable cell colonies were counted. Highest number of lactic acid bacteria was reached between 16 and 20 hr. Concentrated rice milk fermented with high GABA-producing strain contained GABA concentrations of $137.17\;{\mu}g/g$ D.W., whereas concentrated fermented milk prepared by conventional method contained GABA of $1.29\;{\mu}g/g$ D.W. Sensory evaluation panelists gave favorable ratings to fermented rice milk containing high GABA concentration.