• Microbiology and Biotechnology Letters
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• v.25 no.1
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• pp.56-61
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• 1997

An alkaline protease producing microorganism was isolated from korean traditional Meju and identified as Scopulariopsis brevicaulis. The optimum culture condition of Scopulariopsis brevicaulis for the production of alkaline protease was as follow: 2% soluble starch, 0.2$, tryptophan, 0.1% (NH$_{4}$) $_{2}$S$_{2}$O$_{8}$ 0.2% NaHPO$_{4}$, pH 7.5, 35$\CIRC $C. The optimum pH and temperature for the enzyme activity of alkaline protease producing Scopulariopsis brevicaulis were pH 9.0 and 50$\circ $C, respectively. The enzyme was relatively stable at pH 6.0~11.0 and at temperature below 40$\circ $C. The activity of the enzyme was inhibited by Hg$^{2+}$ whereas Cu$^{2+}$ gave rather activating effects on the enzyme activity. Phenylmethanesulfonyl fluoride inhibited the enzyme activity. This result indicates that serine is very important role in this enzyme. Km value for casein was 1.2410$^{4}$ M/L, V$_{max}$ value for casein was 25.99 $\mu $g/min. This enzyme hydrolyzed casein more rapidly than the hemoglobin.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.5
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• pp.337-340
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• 2001

A galactooligosaccharide(GalOS)-producing yeast, OE-20 was selected from forty seven strains of yeast growing in Korean traditional Meju (cooked soybean) and the yeast was tentatively identified as Kluyveromyces maxianus var lactis by its morphology and fermentation profile. A maximum yield of 25.1%(w/w) GalOS, which corresponds to 25.1 g of GalOS per liter, was obtained from the reaction of 100 g per liter of lactose solution at 3$0^{\circ}C$, pH 7.0 for 18 h with an intracellular crude $\beta$-galactosidase. Glucose and galactosidase were found to inhibit GalOS formation. The GalOS that were purified by active carbon and celite 545 column chromatography were supplemented in MRS media and a stimulated growth was observed of some intestinal bacteria. In particular the growth rate of Bifidobacterium infantis in the GalOS containing MRS broth increased up to 12.5% compared to that of the MRS-glucose broth during a 48h incubation period.

• Food Science and Biotechnology
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• v.15 no.2
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• pp.298-302
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• 2006

Kochujang was fermented using hot red pepper, meju prepared with soybean and rice, and malt-digested syrup. To reduce salt content, mustard powder (1.2%, w/w) was added to Korean traditional kochujang with 4-10% salt, and microbial characteristics, enzyme activities, and gas formation in kochujang were evaluated during fermentation for 120 days at $25^{\circ}C$. Yeast numbers of all treatments maintained 2.43-2.86 log CFU/g up to 60 days fermentation, indicating salt concentration had no effect on yeast count. Activities of ${\alpha}$- and ${\beta}$-amylases, and neutral and acidic proteases of kochujang added with mustard powder were slightly higher than those of control group. Total accumulative volume of gas produced during fermentation of kochujang without mustard powder (control group) was 5,892 mL/pack, but decreased to 34-99 mL/pack in low-salted kochujang (4 and 6% salt) added with mustard powder. Major gas produced was carbon dioxide (79-80%) with oxygen content less than 1.25%(v/v). Results indicate salt concentration of kochujang could be lowered up to 6-8% by addition of mustard powder without gas formation and quality alteration during distribution.

• The Korean Journal of Mycology
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• v.24 no.4 s.79
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• pp.280-292
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• 1996

The fungal isolates of Mucorales, directly collected from Korean traditional raw materials of Nuruk (raw material for Korean rice wine) and Meju (raw material for Korean soysauces), were compared with those of Rhizopus oryzae purchased. The fungal isolates of Rhizopus, Mucor, and Absidia mostly identified as based on the morphological observations, were evaluated with the PCR-polymorphic bands. The PCR-polymorphic bands of the genomic DNA reacted with the primers of OPD series tenmer were various, but showed averaged 4 to 6 in the agarose-electrophoresis. The dissimilarity coefficient (DC) between two isolates were compared by the cluster analyses, dendrogams and polar ordinations. The isolates of R. oryzae known. showed several groupings within the lower value of DC and were divided to two groups of amylo-process and other fungi with other purposes. The isolates unidentified were identified by the DC made of this results. Taxonomy of these isolates made by the morphological observations were consistent with those resulted above in most case but not in all aspects. More works were needed with the isolates known for detail informations of Mucorales.

• Microbiology and Biotechnology Letters
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• v.47 no.2
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• pp.234-241
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• 2019

In Korea, traditional doenjang is manufactured using the conventional method at home and by small-scale enterprises. Because this age-old process depends on natural inoculation of various microorganisms, it is difficult to reproduce or maintain consistency in the final product quality across batches. Moreover, doenjang occasionally prepared by this method raises safety concerns related to aflatoxin, biogenic amine, and Bacillus cereus contamination. To develop starters that can be conveniently used at home or in small industry settings for the manufacturing of safe and flavor-improved doenjang, autochthonous microbe starters were developed in dried forms as ready-to-use starters. Each starter powder prepared by heat- or freeze-drying methods remained stable even after 24-week storage. These ready- to-use starter powders were successfully applied to lab-scale fermentation for the production of safe and flavor-improved doenjang. We believe that these ready-to-use starter powders will benefit small-scale enterprises in the manufacturing of doenjang of good reproducible quality.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.1
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• pp.32-38
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• 2002

The characteristics of blown color of Korean traditional soy sauces under different processing conditions were investigated in this research. As for meju type, traditional and modified mejus were used. The samples were produced from four levels of aging time. 0 day, 60 days, 120 days and 180 days in both clay jar and glass jar. Color intensity of soy sauce was probed with different mothods. In terms of colorcharacteristics, the absorbance at 420 nm seemed to reflect the brown color intensity of soy sauces. UV-VIS spectra of the soy sauce with traditional meiu revealed that the absorbance at 235 nm was produced during the soaking period whereas that at 410 nm was created during the aging process and only round in the spectra of soy sauce aged for 180 days. As for the soy sauce with modified meiu, the maximum absorbance was focused at 235 nm which were prepared during soaking period.

• Applied Biological Chemistry
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• v.24 no.3
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• pp.200-205
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• 1981

Some chemical components, absorbance at 450nm and color of traditional and improved soysauce during fermentation were investigated. The traditional soysauce was made from soybean Meju and the improved soysauces were prepared from Kojis of various mixtures of soybean and wheat. The contents of reducing sugar were higher in the improved soysauces than in the traditional soysauce and it increased with proportion to the mixing amount of wheat. The contents of total nitrogen and amino nitrogen were increased gradually during fermentation and, in the improved soysauce, it increased with the amount of soybean. The changes of the absorbance and the chromaticity were greaser in the traditional soysauce than in the improved soysauce during fermentation. The increase of absorbance and the chromaticity was greater in the improved soysauce than that of the traditional soysauce during heating process. In the improved soysauce, the greater the amounts of wheat in Koji, the greater the increase of color.

• Korean Journal of Food Science and Technology
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• v.44 no.2
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• pp.228-234
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• 2012

The varying characteristics between traditional and commercial soy sauce may be initiated by raw materials and fermentation techniques for the production of $meju$ and $koji$. We examined properties regarding polysaccharides isolated from commercial soy sauce made by the $koji$ process (CSP-0) and Korean traditional soy sauce made by the $meju$ process (KTSP-0) as well as their immuno-stimulating activities. KTSP-0 had rhamnogalacturonan II (RG-II) including 1.1% of unusual monosaccharides 3-deoxy-D-$manno$-2-octulosonic acid (KDO). Anti-complementary activities of CSP-0 and KTSP- 0 were increased dose-dependently but KTSP-0 (64.7%) was higher than CSP-0 (56%) at $1,000{\mu}g/mL$. C3 activation products were identified by crossed immuno-electrophoresis. CSP-0 caused complementary activations $via$ only classical pathway while KTSP-0 caused complementary activations $via$ both alternative and classical pathways. KTSP-0 significantly increased the secretion of interleukin (IL)-6 at $8-1,000{\mu}g/mL$ and IL-12 at $40{\mu}g/mL$ on macrophages. The results suggest that the immuno-stimulating activity of KTSP-0 is greater than that of CSP-0 from anti-complementary activity.

• Food Science and Preservation
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• v.24 no.8
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• pp.1188-1194
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• 2017

Gochujang, a traditional Korean food, is fermented by mixing red pepper powder, various grain, meju and salt. Changes in the kind of ingredients and fermentation method could increase health functionalities. In this study, in vivo anti-colitis effects of gochujang prepared with mixed grains, bamboo salt baked 3 times and meju starters on DSS-induced colitis in C57BL/6 mice were studied. We prepared gochujang prepared with mixed grains (MG), bamboo salt, and Aspergillus oryzae (A) and Baccillus subtilis (B) mixed starters (MG-AB) and gochujang prepared with MG, bamboo salt and A, B and Lactobacillus plantarum (L) mixed starters (MG-ABL). MG-AB and MG-ABL significantly increased body weight and colon length compared to the control (p<0.05). MG-ABL showed significantly decreased interleukin-6 (IL-6) expression in serum compared to the control and MG-AB group (p<0.05). MG-ABL also regulated mRNA and protein levels of pro-apoptotic Bcl-2-associated X protein (Bax) and anti-apoptotic B-cell lymphoma-2 (Bcl-2) in the mice colon tissue (p<0.05). Therefore, MG-ABL exhibited the increased anticolitis effects by inhibiting damage of colon tissue, probably by regulating a pro-inflammatory cytokine of IL-6 and regulated apoptosis related genes. These results indicated that gochujang changed with good ingredients and starters had colitis preventive effects and might be due to active compounds in mixed grain and bamboo salt, and produced by L during the fermentation of gochujang.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1635-1641
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• 1999

Bacillus subtilis PCA20-3 was isolated from meju and was found to produce a protease. The strain produced the maximum amount of enzyme in the medium containing soytone (0.2%), soluble starch (2%), $(NH_4)_2SO_4\;(0.1%),\;CaCl_2(0.1%),\;yeast\;extract\;(0.01%),\;K_2HPO_4\;(0.1%),\;and\;KH_2PO_4\;(0.1%)$. Protease was first concentrated by ammonium sulfate (80% saturation, w/v) precipitation of culture supernatant. Then the enzyme was purified by column chromatography using CM Sephadex C-50. The collected proteins were rechromatographed using Sephadex G-100 gel filtration column. The fraction with protease active from Sephadex G-100 gel chromatography was found to be pure when examined by SDS-polyacrylamide gel electrophoresis and YMC-pak reverse phase chromatography. Specific activity, yield and purity were 76 U/mg. 2.7%, and 7.6 fold, respectively. The molecular weight of the enzyme was estimated to be 31.5 kDa by SDS-PAGE. The number of amino acids calculated from molecular weight was evaluated about 321 residues. N-terminal sequence of the enzyme was $Val^1-Pro^2-Tyr^3-Gly^4-Val^5-Ser^6-Gln^7-Gly^8-Lys^9-Ala^{10}$.