• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.433-440
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• 1999

To develop Korean-style hot sauce using red pepper powder and/or Kochujang, its physiochemical and microbiological characteristics were investigated during storage at 20 and $30^{\circ}C$ for 56 days. The capsanthin contents and the value of surface color decreased during storage, but pH and titratable acidity were not changed. The sensory quality showed a decreased tendency during storage. Among the microorganisms, viable cell count decreased, but yeast, lactic acid bacteria and E. coli were not detected during storage. From the correlationship between sensory color and capsanthin content, the shelf-lives of hot sauce were predicted to be 221.7 days at $20^{\circ}C$, and 85.3 days at $30^{\circ}C$. While they were 230.0 days at $20^{\circ}C$ and 70.0 days at $30^{\circ}C$ in case of using Kochujang, hot sauce using both materials showed shelf-lives of 204.0 days at $20^{\circ}C$, 67.3 days at $30^{\circ}C$, respectively.

• Journal of Life Science
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• v.13 no.6
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• pp.879-888
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• 2003

In order to measure the enzyme activity of 5-epi-aristolochene hydroxylase, one of cytochrome P450 (P450) enzymes in eicitor-treated pepper cell, we used in vivo assay method and demonstrated a dramatic suppression of the activity by P450-inhibitors, ancymidol and ketocornazole. Using RT-PCR method with degenerate primer of the well conserved domains found within most P450-enzymes, and using cDNA library screening method, one distinct cDNA, being designated P450Hy01, was successfully isolated from elicitor-treated pepper cells. P450Hy01 mRNA was all induced in elicitor-treated cells whereas never induced in control cells. Moreover, levels of P450Hy01 expression were highly correlated with the levels of extracellular capsidiol production by different elicitors in cell cultures. P450Hy01 transcript was also induced by several other elicitors such as, cellulase, arachidonic acid, jasmonic acid, yeast extract as well as UV stress. P450Hy01 sequence contained high probability amino acid matches to known Plant P450 genes and ORF with a conserved FxxGxRxCxG heme-binding domain. P450Hy01 cDNA showed 98% of homology in sequence of nucleotide as well as amino acid to 5-epi-aristolochene-1, 3-hydroxylase (5EAl, 3H) which has been isolated in tobacco cells, suggesting that P450Hy01 is prominent candidate gene for P450-enzyme encoding 5EAl, 3H in pepper cell.

• Korean Journal of Microbiology
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• v.50 no.4
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• pp.360-367
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• 2014

Candida albicans is an opportunistic and the most prevalent fungal pathogen that can cause superficial and systemic infections in immunocompromised patients. C. albicans can promote the transition from budding yeast to filamentous form, generating biofilms. Infections associated with C. albicans biofilms are frequently resistant to conventional antifungal therapy. Therefore, the development of more effective antifungal drugs related with biofilm formation is required urgently. The roots of Rheum undulatum have been used for medicinal purposes in Korea and China traditionally. The aim of present study was to evaluate the effect of R. undulatum extract upon preformed biofilms of 12 clinical C. albicans isolates and the antifungal activities. Its effect on preformed biofilms was evaluated using XTT reduction assay, and metabolic activity of all tested strains was reduced significantly ($49.4{\pm}6.0%$) at 0.098 mg/ml R. undulatum. The R. undulatum extract blocked the adhesion of C. albicans biofilms to polystyrene surfaces, and damaged the cell membrane integrity of C. albicans which was analyzed by CFDA, AM, and propidium iodide double staining. It caused cell lysis which was observed by Confocal laser scanning and phase contrast microscope after propidium iodide and neutral red staining, respectively. Membrane permeability was changed as evidenced by crystal violet uptake. The data suggest that R. undulatum inhibits biofilm formation by C. albicans, which can be associated with the damage of the cell membrane integrity, the changes in the membrane permeability and the cell lysis of C. albicans.

• Korean Journal of Poultry Science
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• v.37 no.3
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• pp.215-219
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• 2010

The applicability of electronic nose was tested to detect lipid peroxidation in chickens and to measure antioxidant effect of astaxanthin in chicken carcasses. Two sources of astaxanthin were fed to 62-wk-old spent laying hens to improve meat quality: natural astaxanthin (NA) from the red yeast, Phaffia rhodozyma, and synthetic astaxanthin (SA) from chemical synthesis. One hundred forty four ISA Brown laying hens were used in a 6-wk feeding trial. Three treatments consisted of the basal diet (control), SA (100 mg astaxanthin/kg basal diet) and NA (50 mg astaxanthin/kg basal diet). The astaxanthin levels of SA and NA were set to give a similar degree of skin pigmentation. After 6-wk feeding of astaxanthin, the skins from NA and SA were discriminated from the control by electronic nose. However, electronic nose failed to distinguish between SA and NA skins after 6-wk feeding. The astaxanthin level differences between skins of SA and NA were not remarkable during the 6-wk trial. The lipid peroxide formation in skin was significantly decreased by SA but not by NA. The antioxidation effect of SA was detected by electronic nose because SA skin was discriminated from others. NA was a better pigmentation agent than SA, but the reverse was true in antioxidation. Electronic nose is applicable for detecting astaxanthin in chicken, and meat off-flavor caused by lipid peroxidation during storage.

• Journal of Microbiology and Biotechnology
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• v.25 no.12
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• pp.1989-1996
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• 2015

Ice-binding proteins (IBPs) can inhibit ice recrystallization (IR), a major cause of cell death during cryopreservation. IBPs are hypothesized to improve cell viability after cryopreservation by alleviating the cryoinjury caused by IR. In our previous studies, we showed that supplementation of the freezing medium with the recombinant IBP of the Arctic yeast Glaciozyma sp. (designated as LeIBP) could reduce post-thaw hemolysis of human red blood cells and increase the survival of cryopreserved diatoms. Here, we showed that LeIBP could improve the viability of cryopreserved mammalian cells. Human cervical cancer cells (HeLa), mouse fibroblasts (NIH/3T3), human preosteoblasts (MC3T3-E1), Chinese hamster ovary cells (CHO-K1), and human keratinocytes (HaCaT) were evaluated. These mammalian cells were frozen in dimethyl sulfoxide (DMSO)/fetal bovine serum (FBS) solution with or without 0.1 mg/ml LeIBP at a cooling rate of -1℃/min in a -80℃ freezer overnight. The minimum effective concentration (0.1 mg/ml) of LeIBP was determined, based on the viability of HeLa cells after treatment with LeIBP during cryopreservation and the IR inhibition assay results. The post-thaw viability of mammalian cells was examined. In all cases, cell viability was significantly enhanced by more than 10% by LeIBP supplementation in 5% DMSO/5% FBS: viability increased by 20% for HeLa cells, 28% for NIH/3T3 cells, 21% for MC3T3-E1, 10% for CHO-K1, and 20% for HaCaT. Furthermore, addition of LeIBP reduced the concentrations of toxic DMSO and FBS down to 5%. Therefore, we demonstrated that LeIBP can increase the viability of cryopreserved mammalian cells by inhibiting IR.

• Journal of Microbiology and Biotechnology
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• v.27 no.6
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• pp.1098-1105
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• 2017

Vesicular stomatitis virus G glycoprotein (VSV-G) has been widely used for pseudotyping retroviral, lentiviral, and artificial viral vectors. The objective of this study was to establish a potential approach for large-scale production of VSV-G. To this end, VSV-G was cloned with an N-terminal His-tag into Pichia pastoris expression vector pPIC3.5K. Three clones ($Mut^s$) containing the VSV-G expression cassette were identified by PCR. All clones proliferated normally in expansion medium, whereas the proliferation was reduced significantly under induction conditions. VSV-G protein was detected in cell lysates by western blot analysis, and the highest expression level was observed at 96 h post induction. VSV-G could also be obtained from the condition medium of yeast protoplasts. Furthermore, VSV-G could be incorporated into Ad293 cells and was able to induce cell fusion, leading to the transfer of cytoplasmic protein. Finally, VSV-G-mediated DNA transfection was assayed by flow cytometry and luciferase measurement. Incubation of VSV-G lysate with the pGL3-control DNA complex increased the luciferase activity in Ad293 and HeLa cells by about 3-fold. Likewise, incubation of VSV-G lysate with the pCMV-DsRed DNA complex improved the transfection efficiency into Ad293 by 10% and into HeLa cells by about 1-fold. In conclusion, these results demonstrate that VSV-G could be produced from P. pastoris with biofunctionalities, demonstrating that large-scale production of the viral glycoprotein is feasible.

• Journal of Microbiology and Biotechnology
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• v.17 no.7
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• pp.1221-1225
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• 2007

A ${\beta}$-ionone-resistant mutant strain isolated from the red yeast Xanthophyllomyces dendrorhous KCTC 7704 was used for batch and continuous fermentation kinetic studies with glucose media in a 2.5-1 jar fermentor at $22^{\circ}C$ and pH 4.5. The kinetic pattern of growth and carotenoid concentration in the batch fermentations exhibited a so-called mixed-growth-associated product formation, possibly due to the fact that the content of intracellular carotenoids depends on the degree of physical maturation toward adulthood. To determine the maximum specific growth rate constant (${\mu}_m$) and Monod constant ($K_s$) for the mutant, glucose-limited continuous culture studies were performed at different dilution rates within a range of $0.02-0.10\;h^{-1}$. A reciprocal plot of the steady-state data (viz., reciprocal of glucose concentration versus residence time) obtained from continuous culture experiments was used to estimate a ${\mu}_m$ of $0.15\;h^{-1}$ and $k_s$ of 1.19 g/l. The carotenoid content related to the residence time appeared to assume a typical form of saturation kinetics. The maximum carotenoid content ($X_m$) for the mutant was estimated to be $1.04\;{\mu}g/mg$ dry cell weight, and the Lee constant ($k_m$), which was tentatively defined in this work, was found to be 3.0 h.

• Journal of Microbiology and Biotechnology
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• v.1 no.2
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• pp.142-149
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• 1991

Gardenia callus was induced in MS medium containing $10{\;}{\mu}M$ of 2,4 diphenoxy acetic acid (2,4-D), $1{\;}{\mu}M$ kinetin, and 3% sucrose in the dark. $B_5$ medium was identified to be the most adequate medium for cell growth. Indole-3-acetic acid (IAA) was better growth regulator than 2,4-D not only for cell growth but slso for carotenoid production. Ligt also played a critical role on synthesis of carotenoid. Gardenia cells grown in $B_5$ medium could utilize a polysaccharide, soluble starch, as a carbon source. The cell growth was stimulated in $B_5$ medium fortified with 0.2% yeast extract. The optimum pH for cell growth was 5.7. High density cultures can be maintained by increasing inoculum size and medium concentration accordingly. Specific growth rate and mass doubling time were 0.095 $day^{-1}$ and 7.3 days, respectively. The cell immobilized in alginate tends to formulate more enlarged vacuoles containing yellow pigment compared with those of suspended cell. Carotenoid content of immobilized cell was about $264.4{\;}{\mu}g/g$ fresh weight (F.W.) corresponding twice of the content of suspended cell ($112.08{\;}{\mu}g/g$ F.W.). The color of gardenia cell was shifted from yellow to red when carbohydrase-secreting fungus, Trichoderma reesei, was co-cultivated with gardenia cells.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.6
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• pp.845-852
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• 2014

The quality of commercial sauce products was evaluated through pH, soluble solid content, salinity, water activity and microbial analyses. The pH of sauces was 2.38~5.30, soluble solids were between 6.03 and 71.67, and distributions of salt were 0.23~5.00% in 32 commercial sauce products. In addition, water activity of vinegar red pepper sauce and spicy soft tofu stew stock were determined 0.773 and 0.988, respectively. Yeast, mold, Staphylococcus aureus, E. coli and coliform were not detected in any sauces. Higher level of total viable cells (TVC) resulted in pH over 4.2. TVC of shelf-stable sauces was 1.0~3.6 log CFU/g. TVC of seven sauce products was classified as non-potentially hazardous foods by temperature controlled for safety standard (TCS), even though levels were over acceptable guidelines of the USDA (3 log CFU/g). These results indicate that the standard and classification of commercial sauce products should be modified and controlled strictly.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.6 no.1
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• pp.15-29
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• 1993

Yenhwagamchotang has been widely used in treatment of inflammatory disease which is based on Oriental Medical literatures. These studies were attempted experimental effects of Yenhwagamchotang(sample A), Yenhwagamchotang plus Forsythia koreana NAKAI.(sample B), and Yenhwa-gamchotang plus Taraxacum mongolicum HAND- MAZZ(sample C),on the Anti-allergic reaction, the antipyretic action,the anti-inflammatory and the analgesic action,in rats. THe results of the studies were as follow: 1. Vascular permeability responses to intradermal serotonin in rats were showed significant effect at all sample groups. 2. The homologous passive cutaneous anaphylaxis in rats provoked by the IgE-like antibody aganist egg white albumin showed the decreasing effect. 3. The delayed type hypersensitivity responses to picryl chloride in mice were showed significant effect at all sample groups. 4. The delayed type hypersensitivity response to sheep red blood cell in mice were showed significant effect at all sample groups. 5. In anti-pyretic effect by yeast method were showed significant effect at all sample groups. 6. The anti-inflammatory effect by carrageenin method were showed significant effect at all sample groups. 7. The analgesic action by acetic acid method in mice were showed significant effect at all sample groups. According to the above result, Yenhwagamchotang(sample A), Yenhwagamchotang plus Forsythia koreana NAKAI(sample B), AND yenhwagamchotang plus Taraxacum mongolicum HNAN- MAZZ.(sample C ) were concluded to have the anti-allergic reaction, the antipyretic action, the anti-inflammatory, the analgesic action.