• Journal of Ginseng Research
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• v.20 no.3
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• pp.299-306
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• 1996

This study was undertaken to examine the effects of fresh ginseng on the physicochemical and microbiological changes in dongchimi juice fermented under various conditions. The pH was somewhat lower in dongchimi juice added with 2.0% and 4.0% of fresh ginseng than that without ginseng, whereas the titratable acidity was higher in dongchimi juice with 2.0% and 4.0% of ginseng addition than the control. The addition of fresh ginseng to dongchimi preparation increased the numbers of total viable bacteria, lactic acid bacteria including Leuconostac mesenterotdes in dongchimi juice during fermentation. The changes in the counts of lactic acid bacteria were similar to those of total viable cells throughout the experiment except the initial stage of fermentation. However, the number of Leucosfastoc mesenternidgs decreased after the palatable stage. Key words : Panax ginseng C.A. Meyer, dongchlmi juice, pH, titratable acidity, microbiological changes.

• Korean Journal of Veterinary Research
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• v.49 no.2
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• pp.127-133
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• 2009

Salmonella enterica subsp. enterica serovar gallinarum (S. gallinarum) is the agent of fowl typhoid, and the 9R vaccine is a commercial live vaccine for the prevention of fowl typhoid. The aim of this study was to assess the safety and immunogenicity of different brands of S. gallinarum 9R vaccine used in commercial laying chickens in Korea. All 9R strains originated from three different brands showed the same pattern in the biochemical and serological properties, and pulsed field gel electrophoresis (PFGE) profile. But, there was a difference in rhamnose fermentaion, agglutination with Salmonella group $D_1$ antiserum and PFGE pattern between 9R vaccine strain and field S. gallinarum isolates. In laboratory and field trials for assesment of safety and immunogenicity of 9R vaccine, all of the three 9R vaccines showed the same safety in commercial laying chickens. In addition, there was a significant difference between the vaccinated and unvaccinated control groups in mortality and the re-isolation rate of the challenge strain from the tissues (p < 0.05), and no difference by the brands of 9R vaccine. The results from this study indicated that all three different brands of S. gallinarum 9R vaccine showed highly protection against mortality and organ invasion in commercial laying chickens exposed to virulent strains of S. gallinarum.

• Journal of the Korea Organic Resources Recycling Association
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• v.5 no.1
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• pp.1-13
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• 1997

The fermentative conversion of food wastes into feed was investigated by seeding of mixed inoculum YM (Youngjin Environmental co.), and thermotolerant yeast Kl. marxianus. For 6 days' fermentaion, the fermentation method of 2 days' aerobic followed by 4 days' anaerobic was better for the production of organic acids and increasing total microbial population than 6 days' continuous aerobic or anaerobic fermentation. By seeding YM, the total microbial count increased about 100 times of the control group. In addition, Kl. marxianus seeding together with YM increased total viable cell count, but did not increase yeast count significantly.

• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.389-392
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• 1994

Changes in free amino acids and amino nitrogen of traditional kochujang were investigated during 180 days of fermentation. Tested kochujang included Sunchang kochujang prepared with glutinous rice, Boeun kochujang prepared with barley, and Sachun kochujang prepared with wheat. Amino acids remarkably increased during fermentation were methionine, glutamic acid, isoleucine, leucine and tyrosine. However, regardless of kinds of kochujang major free amino acids were serine, aspartic acid, glutamic acid and proline. Glutamic acid was noted as the most contributing to the savory taste of kochujang in relation to the increasing ratio and content among tree amino acids during fermentaion. The correlation coefficent between totals of free amino acids and the contents of amino nitrogen were relatively high (0.87

• Korean Journal of Microbiology
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• v.37 no.3
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• pp.234-238
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• 2001

For the comparison of fermentation pattern of leek kimci with chinese cabbage kimchi, the changes of total viable cell number, Leuconostoc sp. bacteria, Lactobacillus sp. bacteria, pH and total sugar content of twotypes kimchies were investigated during fermentation at $20^{\circ}C$ and $10^{\circ}C$. In chinese cabbage kimchi at $20^{\circ}C$ fermentaion, the numbers of total viable cell, Leuconostoc sp. bacteria and Lactobacillus sp. bacteria reachedthe maximum level on 2nd day and reduced slowly. But in leek kimchi, the maximum numbers of total via-ble cells, Leuconostoc sp. bacteria and Lactobacillus sp. bacteria were obtained after 3 days fermentation,and the cell number of Lactobacillus sp. maintained at the maximum level oyer 15 days. At $10^{\circ}C$ fer-mentation, in both kimchies, the viable cell number of lactic acid bacteria more slowly increased anddecreased than at $20^{\circ}C$. The pH of chinese cabbage kimchi was 4.2 on 3rd day (optimal ripening phase) andmere decreased to 3.5 after 5 days, but in leek kimci the pH 4.2 could be reached after 10 days at $20^{\circ}C$. At $10^{\circ}C$, the optimal ripening pH 4.2 of chinese cabbage kimchi was reached after 6 days, but in leek kimchieven though after 24 days, the pH was maintained oyer 4.3. The total sugar contents of chinese cabbage him-chi and leek kimci were decreased continuously during fermentation. From these results, we know that thefermentation of leek kimchi proceed more slowly than chinese cabbage kimchi by the retardation of lacticacid bacteria growing in leek kimchi.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.196-205
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• 1999

Kochujang prepared by liquid and solid koji using isolated bacteria(Sunchang 1 and Park 2) showing excellent enzyme activities were gamma irradiated at $15{\pm}1.5\;kGy$ to investigate their qualities from the physicochemical, microbiological and enzymatic points of view during fermentaion at $25^{\circ}C$ for 90 days. The amino type nitrogen contents were $0.6{\sim}0.7%$ after 30 days of fermentation. Irradiation completly stopped gas production which is one of biggest problem of kochujang distribution. Enzyme activities were some different according to koji and irradiation treatment. Amino type nitrogen content as one the most important quality indice was higher in kochujang fermented by isolated bacteria (Park 2) than non inoculated traditional kochujang. But sensory quality was not significantly different.

• Korean Journal of Microbiology
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• v.30 no.6
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• pp.546-552
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• 1992

Ethanol-tolerant strain, S. eerevisiae BUI a26 ($alc^r thr^-$) and gJucoamylase-producing strain, S diastatieus AI5a6 (STA+ hom-) were prepared by means of genetic manipulation, Protoplast fusion was carried out to introduce STA gene from AI5a6 strain to BUla26 strain, Protoplast formation was shown at 0,8 M sorbitol and 200 Jig/ml to 400 Jig/ml zymolyase treatment for 2 hours incubation, Fusion frequency was $ 3.25 {\times} 10^{-3}$ to the regenerated protoplast number using PEG 6000 for 90 min incubation. The excellent fusants with genotype of STA- $alc^r thr^-$ hom+/STA+ ($alc^s thr^+$ hom- (2n), F7 and FIO, were selected by ethanol-tolerant, ethanol fermentation, and glucoamylase production tests, Glucoamylase production of AI5a6 showed 2,7 units, but 4.2 or 8.4 units for F7 or FIO fusant at $30^{\circ}C$, Ethanol fermentation from 32% glucose by BUla26 was 14,0%(v/v) in fermentaion medium for 5 days incubation, but 14.5% or 15,0% for F7 or FIO strain, respectively. Ethanol fermentation from 5% starch was 2,0% by F7, or 1.8% by FIO strain in fermentation medium for 5 days fermentation.

• Journal of the Korean Applied Science and Technology
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• v.32 no.4
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• pp.758-766
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• 2015

Dextran is a generic term for a bacterial exopolysaccharide synthesized from sucrose and composed of chains of D-glucose units connected by ${\alpha}$-1,6-linkages by using dextransucrases. Dextran could be used as vicosifying, stabilizing, emulsifying, gelling, bulking, dietary fiber, prebiotics, and water holding agents. We isolated new strain capable of producing dextran from Korean traditional kimchi and identified as Leuconostoc sp. strain JYY4. Batch fermentation was conducted in bioreactor with a working volume of 3 L. The media was MMY and 15% (w/v) sucrose. Mineral medium consisted of $3.0g\;KH_2PO_4$, $0.01g\;FeSO_4$, $H_2O$, $0.01g\;MnSO_4$, $4H_2O$, $0.2g\;MgSO_4\;7H_2O$, 0.01 g NaCl, $0.05g\;CaCl_2$ per 1 liter deionized water. The pH of media was initially adjusted to 6.0. The inoculation rate was 1.0% (v/v) of the working volume. Temperature was maintained at $28^{\circ}C$. The agitation rate was 100 rpm. The production pattern of dextran was associated with the cell growth. After 24 hr dextran reached its highest concentration of 59.4 g/L. The sucrose was consumed completely after 40 hr. Growth reached stationery phase when sucrose became limiting, regardless of the presence of fructose or mannitol. When the specific growth rate was 0.54 hr-1, utilization averaged 5.8 g/L-hr. The yield and productivity of dextran were 80% and 2.0 g/L-hr, respectively. Dextrans produced by were separated to two different size by an alcohol fraction method. The size of high molecular weight dextran (45% alcohol, v/v), less soluble dextran, was between MW 500,000 and 2,000,000. Soluble dextran (55% alcohol, v/v) was between 70,000 and 150,000. The molecular weight average of total dextran (70% alcohol, v/v) was between 150,000 to 500,000. The enzymatic hydrolyzates of total dextran of ATCC 13146 showed branched dextrans by Penicillium dextranase contained of glucose, isomaltose, isomaltotriose, and isomaltooligosaccharides greater than DP4 (degree of polymerization) that had branch points. Compounds greater than DP4 were branched isomaltooligosaacharides. Hydrolysates by the Lipomyces dextranase produced the same composition of oligosaccharides as those by Penicillin dextranase.

• The Korean Journal of Food And Nutrition
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• v.35 no.6
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• pp.435-444
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• 2022

In vitro digestibility and protein digestibility corrected amino acid scores (PDCAAS) were investigated to verify the availability of protein in various Rhizopus oligosporus fermented products of domestic soybean (Glycine max L.) cultivars. Danbaegkong (DBK), Daepung (DP), Daewonkong (DWK), Saedanbaek (SDB), Seonyu (SY), and Cheongja4ho (CJ4) were used as raw samples, which were fermented using commercially available Rhizopus oligosporus for 48 h. All cultivars showed increased crude protein content after fermentation. The crude protein content of DBK and SDB was significantly higher than that of the other samples (55.12% in DBK and 54.22% in SDB) (p<0.001). CJ4 had the highest alanine content of 28.88 mg/g (p<0.001), and no significant difference in cysteine content was detected among the cultivars. In most of the fermented samples, the in vitro digestibility was 0.9 or higher, indicating high protein in the fermented samples. However, it is considered that restrictions on digestion are low. In DWK, the amino acid content and PDCAAS, which together indicate protein quality, were 0.917 and 0.855, respectively, confirming that it was the best cultivar to provide the raw material for fermentation. In conclusion Rhizopus oligosporus fermented soybean products can be considered a prospective source of protein with high utility value.

• Food Science and Preservation
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• v.23 no.5
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• pp.680-688
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• 2016

This study analyzed the changes in physicochemical components of Astragalus membranaceus (AM) fermented with Phellinus linteus. Moisture content, pH, total acidity, total reducing sugar content, extraction yield, free sugar content, free amino acid and isoflavonoid (calycosin, formononetin) were investigated. The moisture content was increased during fermentation with Phellinus linteus. The pH level increased while the total acidity significantly decreased during fermentation. The reducing sugar content were in the range of 0.32~0.61%. The extraction yield using water was higher than that using 80% ethanol. The major free sugars were identified as glucose, fructose, sucrose and the content of free sugars decreased through fermentation. However, the glucose and sucrose contents of the water extracts were increased. In addition, the free amino acid increased significantly during fermentation. Finally, calycosin and formononetins contents in water extracts of after 30 days of AM fermentaion with Phellinus linteus were (3.91 mg/100 g) and (1.38 mg/100 g), respectively. These results suggest that fermentation with Phellinus linteus could be used to increase the bioactivity of AM. The mycelium-fermented AM could be a valuable source of functional material and edible resource for industry.