• Journal of the Korean Society of Industry Convergence
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• v.20 no.4
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• pp.345-350
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• 2017

Saponin is the most pharmaceutical active ingredients of the ginseng plant, it was called "Ginsenoside" which means the Glycoside of ginseng that composed glycosides and aglycones. The human body will absorb the saponin easily if these substrate was decomposed by active microorganism. Fermentation is the most convenient technique to decompose this active ingredients. The purpose of this research was to study the sugar content, pH and acidity development during the ginseng fermentation process. Fresh Korean ginseng and red ginseng extract was used as the main ingredient. The concentrated of pure ginseng extract was added to increase the saponin extract. Furthermore, the mix microbial powder was added as starter to increase the fermentation efficiency. The ginseng was fermented in fermentation chamber at temperature $37^{\circ}C$ during 70 days. In the end of experiment the sugar content was decreased from 24% to 7.65%, The pH was decreased from 6.5 to 3.4, and the acidity level was incresed from 0% to 1.2%.

• Journal of Microbiology and Biotechnology
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• v.26 no.10
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• pp.1687-1695
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• 2016

Ochratoxin A (OTA), a mycotoxin, contaminates agricultural products and poses a serious threat to public health worldwide. Microbiological methods are known to be a promising approach for OTA biodegradation because physical and chemical methods have practical limitations. In the present study, a total of 130 fungal isolates obtained from 65 traditional Korean meju (a fermented starter for fermentation of soybeans) samples were examined for OTA-biodegradation activity using thin-layer chromatography. Two fungal isolates were selected for OTA-biodegradation activity and were identified as Aspergillus tubingensis M036 and M074 through sequence analysis of the beta-tubulin gene. After culturing both A. tubingensis isolates in Soytone-Czapek medium containing OTA (40 ng/ml), OTA-biodegradation activity was analyzed using high-performance liquid chromatography (HPLC). Both A. tubingensis strains degraded OTA by more than 95.0% after 14 days, and the HPLC analysis showed that the OTA biodegradation by the A. tubingensis strains led to the production of ochratoxin α, which is much less toxic than OTA. Moreover, crude enzymes from the cultures of A. tubingensis M036 and M074 led to OTA biodegradation of 97.5% and 91.3% at pH 5, and 80.3% and 75.3% at pH 7, respectively, in a buffer solution containing OTA (40 ng/ml) after 24 h. In addition, the OTA-biodegrading fungi did not exhibit OTA production activity. Our data suggest that A. tubingensis isolates and their enzymes have the potential for practical application to reduce levels of OTA in food and feed.

• Microbiology and Biotechnology Letters
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• v.44 no.1
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• pp.34-39
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• 2016

Wild-type yeast strains were isolated from nuruk, a type of microbial starter culture used for fermenting grains to produce alcoholic products, that was collected from different areas in Korea. Strains were identified based on the analysis of 18S rRNA sequences. Fifty strains shared the highest sequence similarity with Saccharomyces cerevisiae and were designated MBYK1-MBYK50. Among these S. cerevisiae isolates, MBYK45 produced $44.0{\pm}0.3g$ of ethanol from 200 g maltose after incubation at $30^{\circ}C$ for 48 h. Maximum ethanol production of $110.80{\pm}0.81g/l$ with productivity of $3.79{\pm}0.14g^{-1}l^{-1}h^{-1}$ was obtained at optimum culture conditions of pH (6.0), maltose (200 g/l), and temperature ($35^{\circ}C$). This study indicates that the MBYK45 strain of S. cerevisiae, isolated from nuruk, might be suitable for traditional liquor production from malts.

• Journal of Applied Biological Chemistry
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• v.54 no.1
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• pp.51-55
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• 2011

To develop a health-aid preparation of Dioscorea batatas (DB), lactic acid fermentation was attempted using a mixed starter comprising of Lactobacillus acidophilus, Lactobacillus plantarum, Bifidobacterium longum. The anaerobic fermentation of a 10% DB flour suspension gave a uniform suspension of pH 3.65, containing $8{\times}10^6$ CFU/mL lactic acid bacteria. During the administration of the lactic acid fermented DB (FDB) and DB to trinitrobenzene sulfonic acid (TNBS)-induced colitis mouse model, histological lesions, morphological damage, and myeloperoxidase acitivity were significantly reduced at a dosage of 200 and 400 mg/kg/day. Dose-response (200 and 400 mg/kg/day) studies revealed that FDB pre-treatment of mice significantly ameliorated the appearance of diarrhoea and the disruption of colonic architecture. In FDB-pretreated mice, there was a significant reduction in the degree of both neutrophil infiltration (measured as decrease in myeloperoxidase activity) and weight loss rates. Theses findings suggest that FDB exerts beneficial effects in experimental colitis and may be useful in the treatment of inflammatory bowel disease.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.3
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• pp.240-244
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• 2006

To develop a health-aid preparation of Chinese yam (Dioscorea batatas Decne), lactic acid fermentation was attempted using a mixed starter comprising of Lactobacillus acidophilus, Streptococcus thermophilus, and Bifidobacterium bifidus. The anaerobic fermentation of a 5% Chinese yam flour suspension gave a uniform suspension of pH 4.35, containing $7.76{\times}10^6 CFU/mL$ lactic acid bacteria (LAB), and which was found to be acceptable to the panel from a sensory assessment. During the administration of the lactic acid fermented (LAF) Chinese yam to Sprague Dawley rats for 6 weeks, a smaller body weight gain, but greater excretion of feces were observed, implying the creation of a healthy gastrointestine on the administration of LAF Chinese yam, which was also confirmed by the gastrointestinal motility of the feed in rats fed on LAF Chinese yam. The constipation induced by loperamide was further suppressed in a rat group fed on a LAF Chinese yam diet, which was qualified from healthy gastrointestinal flora established by LAB. A serochemical analysis revealed a slight improvement in the blood glucose, neutral lipid and total cholesterol concentrations on administration of LAF Chinese yam, suggesting LAF Chinese yam could be served as a healthy-aid preparation, even for hyperglycemia or hyperlipidemia patients.

• Korean Journal of Agricultural Science
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• v.11 no.1
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• pp.34-44
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• 1984

This experiment was carried out to obtain the fundamental data for development of digestibility and quality enhanced product of soy yogurt. Soy yogurt was processed from raw materials of soybean, defatted soybean and sprouted soybean which inoculated with Lactobacillus acidophilus and Bifidobacterium bifidum as a starter. Changes of chemical compositions, viable cell count and saccharides during processing were investigated including acceptibility of manufactured products. The results were summarized as follows; 1. Defatted soy milk ferment ed with Lactobacillus acidophilus was showed the greatest initial acid productivity and sprouted soy milk was showed the greatest growth of Loctobacillus acidophilus. 2. Acid production was accelerated when 2% glucose was used in soy milk. 3. Addition of reconstituted skim milk in soy milk and defatted roy milk increased acid production but was not showed the effect in the sprouted soy milk. 4. Sprouting soybean, the contents of raffinose and stachyose were decreased but those of glucose was increased. 5. When soy milk was fermented with Lactobacillus acidophilus. the contents of raffinose and stachyose were decreased. 6. As a result of panel test, sprouted soy yogurt which was produced by addition of reconstituted skim milk of 10% showed the greatest flavor and tastes.

• Food Science of Animal Resources
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• v.36 no.1
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• pp.90-99
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• 2016

This study evaluated the effects of two Korean traditional plant extracts (Diospyros kaki THUNB. leaf; DK, and Nelumbo nucifera leaf; NN) on the fermentation, functional and sensory properties of herbal yogurts. Compared to control fermentation, all plant extracts increased acidification rate and reduced the time to complete fermentation (pH 4.5). Supplementation of plant extracts and storage time were found to influence the characteristics of the yogurts, contributing to increased viability of starter culture and phenolic compounds. In particular, the increase in the counts of Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus was highest (2.95 and 1.14 Log CFU/mL respectively) in DK yogurt. Furthermore, supplementation of the plant extracts significantly influenced to increase the antioxidant activity and water holding capacity and to produce volatile compounds. The higher antioxidant activity and water holding capacity were observed in NN yogurt than DK yogurt. Moreover, all of the sensory characteristics were altered by the addition of plant extracts. Addition of plant extracts increased the scores related to flavor, taste, and texture from plain yogurt without a plant extract, as a result of volatile compounds analysis. Thus, the overall preference was increased by plant extracts. Consequently, supplementation of DK and NN extracts in yogurt enhanced the antioxidant activity and physical property, moreover increased the acceptability of yogurt. These findings demonstrate the possibility of using plant extracts as a functional ingredient in the manufacture of herbal yogurt.

• Journal of Microbiology and Biotechnology
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• v.9 no.4
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• pp.498-503
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• 1999

Protease produced from Bacillus sp. FSE-68 was isolated from Meju, a Korean fermented soybean starter, and was purified by a two-consecutive aqueous two-phase system. The change of partition coefficient (K) in the polyethylene glycol (PEG)/potassium phosphate buffer (PPB) aqueous two-phase system was measured at different pHs (6.0- 9.2), PPB concentrations (8-12%), and temperatures (4 and $20^{\circ}C$). As the PPB concentration in the aqueous two-phase system increased, the protease concentration in the top phase (PEG-rich phase) increased, thereby enhancing the partition coefficient. The minimum partition coefficient of the protease was achieved at pH 7.0, whereas that of the total protein was at pH 6.0. The biggest difference in partition coefficients of total protein and protease occurred at pH 6.0. It was interesting to note that the partition coefficient of protease decreased as the temperature increased. The optimum condition of the primary aqueous two-phase extraction of Bacillus sp. FSE-68 was pH 6.0, 14% (w/w) PPB, and 16% (w/w) PEG at $4^{\circ}C$, and the crude enzyme concentration in this system was 50% (w/w). The protease, which was concentrated in the top phase, was further mixed with 15% (w/w) PPB (pH 7.0) in the ratio of 1:1 at $20^{\circ}C$ to elute the bottom phase (PPB-rich phase). Using these steps, the purification fold achieved was 9.2 with a 44.7% yield.

• KSBB Journal
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• v.6 no.4
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• pp.413-424
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• 1991

The optimal condition for manufacturing the yoghurt by using B. bifidum and L. acidophilus was studied. Optimal growth condition of B. bifidum and fermentation effects of B. bifidum, L. acidophilus and Str. thermophilus in mixed culture were investigated separately. Fermentation conditions of B. bifidum were optimized in 12% reconstitued skim milk. The addition of BIOS 2000 to 12% skimmilk was effective on the growth and acid production of B. bifidum. There was asymbiosis among B. bifidum, L. acidophilus and Str. thermophilus in mixed culture which resulted in higher viable cell numbers and acid production. The optimum production of yoghurt was achieved by incubation at $37^{\circ}C$ for 8 hours with 5% mixed starter culture (B. bifidum+L.acidophilus+Str. thermophilus). In this case the effective ratio of B. bifidum: L. acidophilus: Str. thermophilus was 2:1:1 on both acid production and viable cell counts.

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.666-670
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• 2003

Strains producing the protease, which is essential for growth of lactic acid bacteria and fermented kimchi, were screened and identified. Among five types of selected pulmuone kimchis (Jeonlado kimchi, ripened kimchi, yeolmu kimchi, kakdugi, and baechu kimchi), nine strains of bacteria were screened and identified by whole cell protein pattern and API test. The nine strains consisted of one of Lactobacillus sp., one of Leuconostoc sp., six of Bacillus sp., and one of Brevibacillus sp. The protease activities of these strains were compared with known strains (Bac. subtilis KCCM 12248 and Bac. licheniformis KCCM 11851) producing protease. Among tested strains, K-2 (Brevibacillus sp.) showed the highest value (0.11 unit/mg) in protease activity.