• Microbiology and Biotechnology Letters
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• v.9 no.4
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• pp.231-236
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• 1981

Studies were made on the optimal conditions of sterilization for Streptococcus pyogenes treated with heat. The results were as follows: The optimal temperature on growth of Streptococcus pyogenes was 37$^{\circ}C$ and mean generation time was 20 minutes in the logarithmic growth phase. The suspension of Streptococcus pyogenes, adjusted to pH 6-9 and treated with heat at 5$0^{\circ}C$, showed logarithmic death rate. Specific death rate constant(k) values at pH 6-9 were 0.1448, 0.1194. 0.1273 and 0.1707 minute$^{-1}$ , respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.1
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• pp.109-114
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• 2006

For the purpose of oligosaccharide production from alginate, the main component in cell walls of brown algae, the alginate degrading bacteria have been screened from the seaweeds and soil. Among the isolated 69 strains, one strain showing the highest degrading activity was selected and identified as Bacillus licheniformis strain. The adequate sodium alginate concentration for growing the Bacillus licheniformis was $2.0\%$. The effective nitrogen source is nutrient broth $(0.1\%)$, and optimum initial pH, NaCl concentration, temperature and incubation time to produce the alginate degrading enzyme were 7.5, $2\%,\;30{\pm}2^{\circ}C$, and 144 hrs, respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.4
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• pp.251-258
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• 2020

To investigate the suitable growing area for Italian ryegrass (cv. Kowinearly and cv. Green-Call), we survey the different effects of climatic conditions on plant growth in the east (hereafter termed Yeongdong) and west (hereafter termed Yeongseo) of the passes in Gangwon Province. The Italian ryegrass was grown in Gangneung of Yeongdong and Wonju and Chuncheon of Yeongseo. The plants showed growth differences depending on the cultivated regions between before and after wintering. The Italian ryegrass for pre-wintering showed the relatively long length of plant height in Wonju. While, we observed the relatively tall plants for growing- and harvesting-period after wintering in Gangneung. The increased plant height in Gangneung was closely related to all climatic conditions for the growing period and mean- and lowest-temperature for the harvesting period, respectively. The amount of dry matter was 7,490 kg/ha for Kowinearly and 6,490 kg/ha for Green-Call in Gangneung, which has a higher yield than Chuncheon and Wonju. The relative yield index of dry matter was 77% (Kowinearly) and 78% (Green-Call) in Chuncheon and 84% (Kowinearly) and 71% (Green-Call) in Wonju compared to Gangneung as the standard region. Thus, we suggest that Chuncheon and Wonju are the possible areas for cultivation of Italian ryegrass, considering that Gangneung was the optimum growing area in Gangwon Province.

• Food Engineering Progress
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• v.14 no.1
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• pp.65-74
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• 2010

Culture conditions of L. plantarum TJ-LP-002, the garlic resistant strain isolated from pakimchi (green onion kimchi), were investigated for the use of feed additives. Acetic acid, citric acid, lactic acid, and tartaric acid were detected in the culture supernatant, and especially the concentrations of lactic acid and acetic acid significantly increased during cultivation. The antimicrobial activity of L. plantarum TJ-LP-002 was not affected by proteases, calatase or cellulase, which showed that the antimicrobial activity might be due to the production of acids rather than proteinaceous antimicrobial substances. L. plantarum TJ-LP-002 was resistant to neomycin sulfate, spectinomycin dihydrochloride, and lincomycin hydrochloride, sensitive to streptomycin sulfate, and intermediate resistant to ampicillin trihydrate, chloramphenicol, erythromycin, tetracycline hydrochloride, and kanamycin sulfate. The optimum initial pH of medium, fermentation temperature and time for the cell growth and antibacterial activity were pH 7.0, 30${^{\circ}C}$ and 24hr, respectively. The optimal composition of culture medium for the cell growth and antimicrobial activity was 3%(w/v) glucose as a carbon source, 3%(w/v) yeast extract as a nitrogen source, and manganese sulfate and ammonium citrate as inorganic salts. The combinatorial supplementation of these inorganic salts, rather than sole addition as an inorganic salt, resulted in better antibacterial activity.

• Microbiology and Biotechnology Letters
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• v.20 no.3
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• pp.348-354
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• 1992

In order to improve the productivity of invertase by recombinant Saccharomyces cerevisiae containing SUC2 gene, the effect of amino acids and dissolved oxygen concentration on the gene expression was investigated. Optimal concentrations of leucine and histidine for cell growth and cloned gene expression were 0.03 gig and 0.04 gig, respectively, expressed as the ratio of amino acid/glucose. The lack or excess of leucine and histidine has inhibitory effect on cell growth and invertase expression. In batch culture, the less aeration was, the higher invertase activity was. In continuous culture at a dilution rate of 0.09 h 1 with controlled dissolved oxygen tension, invertase activity increased dramatically at DOT levels below 5% air saturation, and a maximum activity of 215.54 KUlg cell was obtained under unaerated condition.

• Microbiology and Biotechnology Letters
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• v.17 no.2
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• pp.148-153
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• 1989

A strain of alkalophilic Bacillus sp. YC-335 has been isolated from soil. The strain was capable of producing large amount of cyclodextrin glycosyl transferase (CGTase) in the culture broth. The preferable medium composition has been determined to be as follows : 1.5% soluble starch, 5% corn steep liquor, 0.1% $K_2$HPO$_4$, 0.02%mgSO$_4$.7$H_2O$, 1% CaCO$_3$and 1% Na$_2$CO$_3$(pH 10.3). The highest enzyme production was observed after 48 hours of cultivation at 31$^{\circ}C$. The optimum pH and temperature for the activity of crude enzyme were 6.0 and 5$0^{\circ}C$, respectively. The enzyme was stable between pH 5 and 9, and upto 5$0^{\circ}C$. The enzyme converted starch into $\alpha$-, $\beta$- and ${\gamma}$-CD in the relative amounts of 1:10:1.5, respectively.

• Journal of Life Science
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• v.13 no.5
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• pp.559-568
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• 2003

The aim of present study is to investigated on the development of the functional doenjang possessing antioxidative and fibrinolytic activity. A strain, BH-23 showing antioxidative and fibrinolytic activity was isolated from traditionally doenjang, and then identified as Bacillus subtilis based on moophological, physiological, and biochemical characteristics, and named as Bacillus subtilis BH-23. The optimal pH level and temperature conditions were 5.0 and $40^{\circ}C$, NaCl concentration was grown well at 15% Antioxidative and fibrinolytic activity of Bacillus subtilis BH-23 was accoidance with growth conditions of the original state. By comparising with traditionally commercialized doenjang, it is prepared with Bacillus subtilis BH-23. The final results evaluated with positive elements rised above the surface such as color, taste and flavor without ammonia. Therefore, it is safe to assume, doenjang has strong market value in the food industry.

• The Korean Journal of Pesticide Science
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• v.3 no.2
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• pp.1-7
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• 1999

The strain with antibacterial activity was isolated among soil samples collected in Suwon area. The isolated strain was identified as Bacillus sp. YR-1 with respect to its morphological, cultural, and physiological characteristics. Optimal medium for the highest production of antibiotic was composed of sucrose 2.0%(w/v), peptone 2.0%(w/v) and NaCl 0.1%(w/v). The maximum production of antibiotic was shown at $35^{\circ}C$ for 48 hours with the initial pH 7.0.

• Journal of Chitin and Chitosan
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• v.23 no.4
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• pp.285-292
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• 2018

In this study, for the purpose of decomposing food waste, the strain was screened from traditional fermented food and soils. The enzyme activity (protease, amylase, cellulase, lipase) experiment was carried out using the paper disc method in 212 strains isolated from 5% NaCl media. Among them, only the strains having enzyme activity of more than 2 (soil) or more than 4 (traditional fermented food) with the halozone of enzyme activity of 15 mm or more were selected first, and microorganism identification through 16S rRNA sequencing was performed. Finally, were identified such as Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus siamensis, Bacillus licheniformis, Bacillus aquimaris, Bacillus megaterium, Bacillus koreensis, Bacillus stratoshericus, Bacillus aryabhattai, Bacillus safensis, Marinobacter hydrocarbonoclasticus. 11 species of mixed strains were confirmed that the culture time was 24 hours, the incubation temperature was $30^{\circ}C$ and the optimum pH was 7.0. In order to confirm the degree of decomposition of standard food wastes (100 g) by treating 11 kinds of mixed strains (25%), solid content of more than $2000{\mu}m$ was determined to be 103 g for the sterilized water group and 18 g for the mixed strains group. And the rest was decomposed to a size of less than $2000{\mu}m$.

• Korean Journal of Food Science and Technology
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• v.6 no.4
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• pp.231-240
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• 1974

The growth of a mixed yeast culture consisting of Canda tropicalis var. KIST 76 and Tricosporon cutaneum KIST 76-H was compared with that of pure cultures under pilot plant conditions. The mixed culture was judged stable based on the nearly constant ratio of the two organisms at the completion of fermentation. We obtained higher cell yields, protein content and productivity in the mixed culture on n-paraffin than the pure culture of C. tropicalis var. KIST 76. T. cutaneum KIST 76-H did not grow on n-paraffin medium. With the batch cultivation of mixed organisms on n-paraffin, the specific growth rates during the exponential growth phase were 0.24-0.33 $hr^{-1};$ cell yields were 96-106% and productivities were 2.9-3.6g/l. hr. The cells obtained contained 55-58% crude protein and 5.5-6.3% lipid. The critical value of dissolved oxygen concentration Ccrit. and saturation constant, km, are approximately 1.5 ppm and 0.228 ppm respectively. Also we established the optimal conditions for the mixed culture in batch fermentation.